Fix for the refactoring commited yesterday, based on review by Dave Stubbs

[rails.git] / app / controllers / amf_controller.rb

diff --git a/app/controllers/amf_controller.rb b/app/controllers/amf_controller.rb
index 095ae47864addf40f5d4f97029c36f234f991a17..738aa443afc15510e597d128bfe46b6c27618c8a 100644 (file)
--- a/app/controllers/amf_controller.rb
+++ b/app/controllers/amf_controller.rb
@@ -1,982 +1,825 @@
+# amf_controller is a semi-standalone API for Flash clients, particularly 
+# Potlatch. All interaction between Potlatch (as a .SWF application) and the 
+# OSM database takes place using this controller. Messages are 
+# encoded in the Actionscript Message Format (AMF).
+#
+# Helper functions are in /lib/potlatch.rb
+#
+# Author::     editions Systeme D / Richard Fairhurst 2004-2008
+# Licence::    public domain.
+#
+# == General structure
+#
+# Apart from the amf_read and amf_write methods (which distribute the requests
+# from the AMF message), each method generally takes arguments in the order 
+# they were sent by the Potlatch SWF. Do not assume typing has been preserved. 
+# Methods all return an array to the SWF.
+#
+# == API 0.6
+#
+# Note that this requires a patched version of composite_primary_keys 1.1.0
+# (see http://groups.google.com/group/compositekeys/t/a00e7562b677e193) 
+# if you are to run with POTLATCH_USE_SQL=false .
+# 
+# == Debugging
+# 
+# Any method that returns a status code (0 for ok) can also send:
+#      return(-1,"message")            <-- just puts up a dialogue
+#      return(-2,"message")            <-- also asks the user to e-mail me
+# 
+# To write to the Rails log, use RAILS_DEFAULT_LOGGER.info("message").
+

 class AmfController < ApplicationController
   require 'stringio'
 
 class AmfController < ApplicationController
   require 'stringio'
 

+  include Potlatch
+
+  # Help methods for checking boundary sanity and area size
+  include MapBoundary
+

   session :off
   before_filter :check_write_availability
 
   session :off
   before_filter :check_write_availability
 

-  # AMF controller for Potlatch
-  # ---------------------------
-  # All interaction between Potlatch (as a .SWF application) and the 
-  # OSM database takes place using this controller. Messages are 
-  # encoded in the Actionscript Message Format (AMF).
-  #
-  # Public domain. Set your tab width to 4 to read this document. :)
-  # editions Systeme D / Richard Fairhurst 2004-2007
+  # Main AMF handlers: process the raw AMF string (using AMF library) and
+  # calls each action (private method) accordingly.
+  # ** FIXME: refactor to reduce duplication of code across read/write

   
   

-  # to trap errors (getway_old,putway,putpoi,deleteway only):
-  #   return(-1,"message")             <-- just puts up a dialogue
-  #   return(-2,"message")             <-- also asks the user to e-mail me
-  # to log:
-  #   RAILS_DEFAULT_LOGGER.error("Args: #{args[0]}, #{args[1]}, #{args[2]}, #{args[3]}")
-
-  # ====================================================================
-  # Main AMF handler
-
-  # ---- talk  process AMF request
+  def amf_read
+    req=StringIO.new(request.raw_post+0.chr)# Get POST data as request
+                              # (cf http://www.ruby-forum.com/topic/122163)
+    req.read(2)                                                                # Skip version indicator and client ID
+    results={}                                                         # Results of each body

 
 

-  def talk
-    req=StringIO.new(request.raw_post+0.chr)   # Get POST data as request
-                                                                                       # (cf http://www.ruby-forum.com/topic/122163)
-    req.read(2)                                                                        # Skip version indicator and client ID
-    results={}                                                                 # Results of each body
-
-    # -------------

     # Parse request
 
     # Parse request
 

-    headers=getint(req)                                        # Read number of headers
+    headers=AMF.getint(req)                                    # Read number of headers

 
 

-    headers.times do                               # Read each header
-      name=getstring(req)                              #  |
-      req.getc                                         #  | skip boolean
-      value=getvalue(req)                              #  |
-      header["name"]=value                             #  |
+    headers.times do                                           # Read each header
+      name=AMF.getstring(req)                          #  |
+      req.getc                                                         #  | skip boolean
+      value=AMF.getvalue(req)                          #  |
+      header["name"]=value                                     #  |

     end
 
     end
 

-    bodies=getint(req)                                 # Read number of bodies
-    bodies.times do                                    # Read each body
-      message=getstring(req)                   #  | get message name
-      index=getstring(req)                             #  | get index in response sequence
-      bytes=getlong(req)                               #  | get total size in bytes
-      args=getvalue(req)                               #  | get response (probably an array)
+    bodies=AMF.getint(req)                                     # Read number of bodies
+    bodies.times do                                                    # Read each body
+      message=AMF.getstring(req)                       #  | get message name
+      index=AMF.getstring(req)                         #  | get index in response sequence
+      bytes=AMF.getlong(req)                           #  | get total size in bytes
+      args=AMF.getvalue(req)                           #  | get response (probably an array)
+      logger.info "Executing AMF #{message}:#{index}"

 
       case message
 
       case message

-                 when 'getpresets';            results[index]=putdata(index,getpresets)
-                 when 'whichways';                     results[index]=putdata(index,whichways(args))
-                 when 'whichways_deleted';     results[index]=putdata(index,whichways_deleted(args))
-                 when 'getway';                        results[index]=putdata(index,getway(args))
-                 when 'getway_old';            results[index]=putdata(index,getway_old(args))
-                 when 'getway_history';        results[index]=putdata(index,getway_history(args))
-                 when 'putway';                        results[index]=putdata(index,putway(args))
-                 when 'deleteway';                     results[index]=putdata(index,deleteway(args))
-                 when 'putpoi';                        results[index]=putdata(index,putpoi(args))
-                 when 'getpoi';                        results[index]=putdata(index,getpoi(args))
+        when 'getpresets';                     results[index]=AMF.putdata(index,getpresets())
+        when 'whichways';                      results[index]=AMF.putdata(index,whichways(*args))
+        when 'whichways_deleted';      results[index]=AMF.putdata(index,whichways_deleted(*args))
+        when 'getway';                         results[index]=AMF.putdata(index,getway(args[0].to_i))
+        when 'getrelation';                    results[index]=AMF.putdata(index,getrelation(args[0].to_i))
+        when 'getway_old';                     results[index]=AMF.putdata(index,getway_old(args[0].to_i,args[1].to_i))
+        when 'getway_history';         results[index]=AMF.putdata(index,getway_history(args[0].to_i))
+        when 'getnode_history';                results[index]=AMF.putdata(index,getnode_history(args[0].to_i))
+        when 'findgpx';                                results[index]=AMF.putdata(index,findgpx(*args))
+        when 'findrelations';          results[index]=AMF.putdata(index,findrelations(*args))
+        when 'getpoi';                         results[index]=AMF.putdata(index,getpoi(*args))

       end
     end
       end
     end

+    logger.info("encoding AMF results")
+    sendresponse(results)
+  end

 
 

-    # ------------------
-    # Write out response
+  def amf_write
+    req=StringIO.new(request.raw_post+0.chr)
+    req.read(2)
+    results={}
+    renumberednodes={}                                         # Shared across repeated putways
+    renumberedways={}                                          # Shared across repeated putways
+
+    headers=AMF.getint(req)                                    # Read number of headers
+    headers.times do                                           # Read each header
+      name=AMF.getstring(req)                          #  |
+      req.getc                                                         #  | skip boolean
+      value=AMF.getvalue(req)                          #  |
+      header["name"]=value                                     #  |
+    end

 
 

-    RAILS_DEFAULT_LOGGER.info("  Response: start")
-    a,b=results.length.divmod(256)
-       render :content_type => "application/x-amf", :text => proc { |response, output| 
-        output.write 0.chr+0.chr+0.chr+0.chr+a.chr+b.chr
-               results.each do |k,v|
-                 output.write(v)
-               end
-       }
-    RAILS_DEFAULT_LOGGER.info("  Response: end")
+    bodies=AMF.getint(req)                                     # Read number of bodies
+    bodies.times do                                                    # Read each body
+      message=AMF.getstring(req)                       #  | get message name
+      index=AMF.getstring(req)                         #  | get index in response sequence
+      bytes=AMF.getlong(req)                           #  | get total size in bytes
+      args=AMF.getvalue(req)                           #  | get response (probably an array)

 
 

+      case message
+        when 'putway';                         r=putway(renumberednodes,*args)
+                                                                       renumberednodes=r[3]
+                                                                       if r[1] != r[2] then renumberedways[r[1]] = r[2] end
+                                                                       results[index]=AMF.putdata(index,r)
+        when 'putrelation';                    results[index]=AMF.putdata(index,putrelation(renumberednodes, renumberedways, *args))
+        when 'deleteway';                      results[index]=AMF.putdata(index,deleteway(*args))
+        when 'putpoi';                         r=putpoi(*args)
+                                                                       if r[1] != r[2] then renumberednodes[r[1]] = r[2] end
+                                                               results[index]=AMF.putdata(index,r)
+        when 'startchangeset';         results[index]=AMF.putdata(index,startchangeset(*args))
+      end
+    end
+    sendresponse(results)

   end
 
   private
 
   end
 
   private
 

-  # ====================================================================
-  # Remote calls
-
-  # ----- getpresets
-  #          return presets,presetmenus and presetnames arrays
-
-  def getpresets
-    presets={}
-    presetmenus={}; presetmenus['point']=[]; presetmenus['way']=[]; presetmenus['POI']=[]
-    presetnames={}; presetnames['point']={}; presetnames['way']={}; presetnames['POI']={}
-    presettype=''
-    presetcategory=''
-
-    RAILS_DEFAULT_LOGGER.info("  Message: getpresets")
-
-    #          File.open("config/potlatch/presets.txt") do |file|
-
-    # Temporary patch to get around filepath problem
-    # To remove this patch and make the code nice again:
-    # 1. uncomment above line
-    # 2. fix the path in the above line
-    # 3. delete this here document, and the following line (StringIO....)
-
-    txt=<<-EOF
-way/road
-motorway: highway=motorway,ref=(type road number)
-trunk road: highway=trunk,ref=(type road number),name=(type road name)
-primary road: highway=primary,ref=(type road number),name=(type road name)
-secondary road: highway=secondary,ref=(type road number),name=(type road name)
-tertiary road: highway=tertiary,ref=,name=(type road name)
-residential road: highway=residential,ref=,name=(type road name)
-unclassified road: highway=unclassified,ref=,name=(type road name)
-
-way/footway
-footpath: highway=footway,foot=yes
-bridleway: highway=bridleway,foot=yes
-byway: highway=unsurfaced,foot=yes
-permissive path: highway=footway,foot=permissive
-
-way/cycleway
-cycle lane: highway=cycleway,cycleway=lane,ncn_ref=
-cycle track: highway=cycleway,cycleway=track,ncn_ref=
-cycle lane (NCN): highway=cycleway,cycleway=lane,name=(type name here),ncn_ref=(type route number)
-cycle track (NCN): highway=cycleway,cycleway=track,name=(type name here),ncn_ref=(type route number)
-
-way/waterway
-canal: waterway=canal,name=(type name here)
-navigable river: waterway=river,boat=yes,name=(type name here)
-navigable drain: waterway=drain,boat=yes,name=(type name here)
-derelict canal: waterway=derelict_canal,name=(type name here)
-unnavigable river: waterway=river,boat=no,name=(type name here)
-unnavigable drain: waterway=drain,boat=no,name=(type name here)
-stream: waterway=stream,boat=no,name=(type name here)
-
-way/railway
-railway: railway=rail
-tramway: railway=tram
-light railway: railway=light_rail
-preserved railway: railway=preserved
-disused railway tracks: railway=disused
-course of old railway: railway=abandoned
-
-way/natural
-lake: natural=water,landuse=
-forest: landuse=forest,natural=
-
-point/road
-mini roundabout: highway=mini_roundabout
-traffic lights: highway=traffic_signals
-
-point/footway
-bridge: highway=bridge
-gate: highway=gate
-stile: highway=stile
-cattle grid: highway=cattle_grid
-
-point/cycleway
-gate: highway=gate
-
-point/waterway
-lock gate: waterway=lock_gate
-weir: waterway=weir
-aqueduct: waterway=aqueduct
-winding hole: waterway=turning_point
-mooring: waterway=mooring
-
-point/railway
-station: railway=station
-viaduct: railway=viaduct
-level crossing: railway=crossing
-
-point/natural
-peak: natural=peak
-
-POI/road
-car park: amenity=parking
-petrol station: amenity=fuel
-
-POI/cycleway
-bike park: amenity=bicycle_parking
-
-POI/place
-city: place=city,name=(type name here),is_in=(type region or county)
-town: place=town,name=(type name here),is_in=(type region or county)
-suburb: place=suburb,name=(type name here),is_in=(type region or county)
-village: place=village,name=(type name here),is_in=(type region or county)
-hamlet: place=hamlet,name=(type name here),is_in=(type region or county)
-
-POI/tourism
-attraction: tourism=attraction,amenity=,religion=,denomination=
-church: tourism=,amenity=place_of_worship,name=(type name here),religion=christian,denomination=(type denomination here)
-hotel: tourism=hotel,amenity=,religion=,denomination=
-other religious: tourism=,amenity=place_of_worship,name=(type name here),religion=(type religion),denomination=
-post box: amenity=post_box,tourism=,name=,religion=,denomination=
-post office: amenity=post_office,tourism=,name=,religion=,denomination=
-pub: tourism=,amenity=pub,name=(type name here),religion=,denomination=
-
-POI/natural
-peak: natural=peak
-EOF
-
-    StringIO.open(txt) do |file|
-      file.each_line {|line|
-        t=line.chomp
-        if (t=~/(\w+)\/(\w+)/) then
-          presettype=$1
-          presetcategory=$2
-          presetmenus[presettype].push(presetcategory)
-          presetnames[presettype][presetcategory]=["(no preset)"]
-        elsif (t=~/^(.+):\s?(.+)$/) then
-          pre=$1; kv=$2
-          presetnames[presettype][presetcategory].push(pre)
-          presets[pre]={}
-          kv.split(',').each {|a|
-            if (a=~/^(.+)=(.*)$/) then presets[pre][$1]=$2 end
-          }
-        end
-      }
+  # Start new changeset
+  
+  def startchangeset(usertoken, cstags, closeid, closecomment)
+    user = getuserid(usertoken)
+    if !user then return -1,"You are not logged in, so Potlatch can't write any changes to the database." end
+
+    # close previous changeset and add comment
+    if closeid
+      cs = Changeset.find(closeid)
+      cs.set_closed_time_now
+      if closecomment.empty?
+        cs.save!
+      else
+        cs.tags['comment']=closecomment
+        cs.save_with_tags!
+      end

     end
     end

-    [presets,presetmenus,presetnames]
+       
+    # open a new changeset
+    cs = Changeset.new
+    cs.tags = cstags
+    cs.user_id = uid
+    # Don't like the next two lines. These need to be abstracted to the model more/better
+    cs.created_at = Time.now
+    cs.closed_at = Time.new + Changeset::IDLE_TIMEOUT
+    cs.save_with_tags!
+    return [0,cs.id]

   end
 
   end
 

-  # ----- whichways(left,bottom,right,top)
-  #              return array of ways in current bounding box
-  #              at present, instead of using correct (=more complex) SQL to find
-  #              corner-crossing ways, it simply enlarges the bounding box by +/- 0.01
-
-  def whichways(args)
-    xmin = args[0].to_f-0.01
-    ymin = args[1].to_f-0.01
-    xmax = args[2].to_f+0.01
-    ymax = args[3].to_f+0.01
-    baselong    = args[4]
-    basey       = args[5]
-    masterscale = args[6]
-
-    RAILS_DEFAULT_LOGGER.info("  Message: whichways, bbox=#{xmin},#{ymin},#{xmax},#{ymax}")
-
-    waylist = ActiveRecord::Base.connection.select_all("SELECT DISTINCT current_way_nodes.id AS wayid"+
-       "  FROM current_way_nodes,current_nodes,current_ways "+
-       " WHERE current_nodes.id=current_way_nodes.node_id "+
-       "   AND current_nodes.visible=1 "+
-       "   AND current_ways.id=current_way_nodes.id "+
-       "   AND current_ways.visible=1 "+
-       "   AND "+OSM.sql_for_area(ymin, xmin, ymax, xmax, "current_nodes."))
-
-    ways = waylist.collect {|a| a['wayid'].to_i } # get an array of way IDs
-
-    pointlist = ActiveRecord::Base.connection.select_all("SELECT current_nodes.id,current_nodes.latitude*0.0000001 AS lat,current_nodes.longitude*0.0000001 AS lng,current_nodes.tags "+
-       "  FROM current_nodes "+
-       "  LEFT OUTER JOIN current_way_nodes cwn ON cwn.node_id=current_nodes.id "+
-       " WHERE "+OSM.sql_for_area(ymin, xmin, ymax, xmax, "current_nodes.")+
-       "   AND cwn.id IS NULL "+
-       "   AND current_nodes.visible=1")
-
-    points = pointlist.collect {|a| [a['id'],long2coord(a['lng'].to_f,baselong,masterscale),lat2coord(a['lat'].to_f,basey,masterscale),tag2array(a['tags'])]   } # get a list of node ids and their tags
-
-    [ways,points]
-  end
+  # Return presets (default tags, localisation etc.):
+  # uses POTLATCH_PRESETS global, set up in OSM::Potlatch.

 
 

-  # ----- whichways_deleted(left,bottom,right,top)
-  #              return array of deleted ways in current bounding box
-  
-  def whichways_deleted(args)
-    xmin = args[0].to_f-0.01
-    ymin = args[1].to_f-0.01
-    xmax = args[2].to_f+0.01
-    ymax = args[3].to_f+0.01
-    baselong    = args[4]
-    basey       = args[5]
-    masterscale = args[6]
-
-       sql=<<-EOF
-                SELECT DISTINCT current_ways.id 
-                  FROM current_nodes,way_nodes,current_ways 
-                 WHERE #{OSM.sql_for_area(ymin, xmin, ymax, xmax, "current_nodes.")} 
-                       AND way_nodes.node_id=current_nodes.id 
-                       AND way_nodes.id=current_ways.id 
-                       AND current_nodes.visible=0 
-                       AND current_ways.visible=0 
-       EOF
-    waylist = ActiveRecord::Base.connection.select_all(sql)
-    ways = waylist.collect {|a| a['id'].to_i }
-       [ways]
+  def getpresets() #:doc:
+    return POTLATCH_PRESETS

   end
   end

-  
-  # ----- getway (objectname, way, baselong, basey, masterscale)
-  #              returns objectname, array of co-ordinates, attributes,
-  #                              xmin,xmax,ymin,ymax
-
-  def getway(args)
-    objname,wayid,baselong,basey,masterscale=args
-    wayid = wayid.to_i
-    points = []
-    xmin = ymin =  999999
-    xmax = ymax = -999999
-
-    RAILS_DEFAULT_LOGGER.info("  Message: getway, id=#{wayid}")
-
-    readwayquery(wayid).each {|row|
-      points<<[long2coord(row['longitude'].to_f,baselong,masterscale),lat2coord(row['latitude'].to_f,basey,masterscale),row['id'].to_i,nil,tag2array(row['tags'])]
-      xmin = [xmin,row['longitude'].to_f].min
-      xmax = [xmax,row['longitude'].to_f].max
-      ymin = [ymin,row['latitude'].to_f].min
-      ymax = [ymax,row['latitude'].to_f].max
-    }
-
-    attributes={}
-    attrlist=ActiveRecord::Base.connection.select_all "SELECT k,v FROM current_way_tags WHERE id=#{wayid}"
-    attrlist.each {|a| attributes[a['k'].gsub(':','|')]=a['v'] }

 
 

-    [objname,points,attributes,xmin,xmax,ymin,ymax]
-  end
-  
-  # -----      getway_old (objectname, way, version, baselong, basey, masterscale)
-  #                    returns old version of way
+  # Find all the ways, POI nodes (i.e. not part of ways), and relations
+  # in a given bounding box. Nodes are returned in full; ways and relations 
+  # are IDs only. 
+
+  def whichways(xmin, ymin, xmax, ymax) #:doc:
+    xmin -= 0.01; ymin -= 0.01
+    xmax += 0.01; ymax += 0.01
+    
+    # check boundary is sane and area within defined
+    # see /config/application.yml
+    begin
+      check_boundaries(xmin, ymin, xmax, ymax)
+    rescue Exception => err
+      return [-2,"Sorry - I can't get the map for that area."]
+    end

 
 

-  def getway_old(args)
-    RAILS_DEFAULT_LOGGER.info("  Message: getway_old (server is #{SERVER_URL})")
-       if SERVER_URL=="www.openstreetmap.org" then return -1,"Revert is not currently enabled on the OpenStreetMap server." end
-       
-    objname,wayid,version,baselong,basey,masterscale=args
-    wayid = wayid.to_i
-    version = version.to_i
-    xmin = ymin =  999999
-    xmax = ymax = -999999
-       points=[]
-       if version<0
-         historic=false
-         version=getlastversion(wayid,version)
-       else
-         historic=true
-       end
-       readwayquery_old(wayid,version,historic).each { |row|
-      points<<[long2coord(row['longitude'].to_f,baselong,masterscale),lat2coord(row['latitude'].to_f,basey,masterscale),row['id'].to_i,row['visible'].to_i,tag2array(row['tags'].to_s)]
-      xmin=[xmin,row['longitude'].to_f].min
-      xmax=[xmax,row['longitude'].to_f].max
-      ymin=[ymin,row['latitude' ].to_f].min
-      ymax=[ymax,row['latitude' ].to_f].max
-       }
-
-       # get tags from this version
-    attributes={}
-    attrlist=ActiveRecord::Base.connection.select_all "SELECT k,v FROM way_tags WHERE id=#{wayid} AND version=#{version}"
-    attrlist.each {|a| attributes[a['k'].gsub(':','|')]=a['v'] }
-       attributes['history']="Retrieved from v"+version.to_s
-
-    [0,objname,points,attributes,xmin,xmax,ymin,ymax,version]
-  end
+    if POTLATCH_USE_SQL then
+      ways = sql_find_ways_in_area(xmin, ymin, xmax, ymax)
+      points = sql_find_pois_in_area(xmin, ymin, xmax, ymax)
+      relations = sql_find_relations_in_area_and_ways(xmin, ymin, xmax, ymax, ways.collect {|x| x[0]})
+    else
+      # find the way ids in an area
+      nodes_in_area = Node.find_by_area(ymin, xmin, ymax, xmax, :conditions => ["current_nodes.visible = ?", true], :include => :ways)
+      ways = nodes_in_area.collect { |node| 
+        node.ways.collect { |w| [w.id,w.version] }.flatten
+      }.uniq
+      ways.delete([])
+
+      # find the node ids in an area that aren't part of ways
+      nodes_not_used_in_area = nodes_in_area.select { |node| node.ways.empty? }
+      points = nodes_not_used_in_area.collect { |n| [n.id, n.lon, n.lat, n.tags] }
+
+      # find the relations used by those nodes and ways
+      relations = Relation.find_for_nodes(nodes_in_area.collect { |n| n.id }, :conditions => {:visible => true}) +
+                  Relation.find_for_ways(ways.collect { |w| w[0] }, :conditions => {:visible => true})
+      relations = relations.collect { |relation| [relation.id,relation.version] }.uniq
+    end

 
 

-  # -----      getway_history (way)
-  #                    returns array of previous versions (version,timestamp,visible,user)
-  #                    should also show 'created_by'
-
-  def getway_history(wayid)
-       history=[]
-       sql=<<-EOF
-       SELECT version,timestamp,visible,display_name,data_public
-         FROM ways,users
-        WHERE ways.id=#{wayid}
-          AND ways.user_id=users.id
-        ORDER BY version DESC
-       EOF
-       histlist=ActiveRecord::Base.connection.select_all(sql)
-       histlist.each { |row|
-               if row['data_public'] then user=row['display_name'] else user='anonymous' end
-               history<<[row['version'],row['timestamp'],row['visible'],user]
-       }
-       [history]
+    [0,ways, points, relations]

   end
 
   end
 

-  # -----      putway (user token, way, array of co-ordinates, array of attributes,
-  #                                    baselong, basey, masterscale)
-  #                    returns current way ID, new way ID, hash of renumbered nodes,
-  #                                    xmin,xmax,ymin,ymax
-
-  def putway(args)
-    RAILS_DEFAULT_LOGGER.info("  putway started")
-    usertoken,originalway,points,attributes,oldversion,baselong,basey,masterscale=args
-    uid=getuserid(usertoken)
-    if !uid then return -1,"You are not logged in, so the way could not be saved." end
-
-    RAILS_DEFAULT_LOGGER.info("  putway authenticated happily")
-    db_uqn='unin'+(rand*100).to_i.to_s+uid.to_s+originalway.to_i.abs.to_s+Time.new.to_i.to_s   # temp uniquenodes table name, typically 51 chars
-    db_now='@now'+(rand*100).to_i.to_s+uid.to_s+originalway.to_i.abs.to_s+Time.new.to_i.to_s   # 'now' variable name, typically 51 chars
-    ActiveRecord::Base.connection.execute("SET #{db_now}=NOW()")
-    originalway=originalway.to_i
-       oldversion=oldversion.to_i
-       
-    RAILS_DEFAULT_LOGGER.info("  Message: putway, id=#{originalway}")
+  # Find deleted ways in current bounding box (similar to whichways, but ways
+  # with a deleted node only - not POIs or relations).

 
 

-       # -- Temporary check for null IDs
-       
-       points.each do |a|
-         if a[2]==0 or a[2].nil? then return -2,"Server error - node with id 0 found in way #{originalway}." end
-       end
+  def whichways_deleted(xmin, ymin, xmax, ymax) #:doc:
+    xmin -= 0.01; ymin -= 0.01
+    xmax += 0.01; ymax += 0.01

 
 

-    # -- 3.    read original way into memory
-
-    xc={}; yc={}; tagc={}; vc={}
-    if originalway>0
-      way=originalway
-         if oldversion==0
-           readwayquery(way).each { |row|
-                 id=row['id'].to_i
-                 xc[id]=row['longitude'].to_f
-                 yc[id]=row['latitude' ].to_f
-                 tagc[id]=row['tags']
-                 vc[id]=1
-               }
-         else
-           readwayquery_old(way,oldversion,true).each { |row|
-                 id=row['id'].to_i
-                 if (id>0) then
-                       xc[id]=row['longitude'].to_f
-                       yc[id]=row['latitude' ].to_f
-                       tagc[id]=row['tags']
-                       vc[id]=row['visible'].to_i
-                 end
-               }
-         end
-      ActiveRecord::Base.connection.update("UPDATE current_ways SET timestamp=#{db_now},user_id=#{uid},visible=1 WHERE id=#{way}")
-    else
-      way=ActiveRecord::Base.connection.insert("INSERT INTO current_ways (user_id,timestamp,visible) VALUES (#{uid},#{db_now},1)")
-    end
-
-    # -- 4.    get version by inserting new row into ways
-
-    version=ActiveRecord::Base.connection.insert("INSERT INTO ways (id,user_id,timestamp,visible) VALUES (#{way},#{uid},#{db_now},1)")
-
-    # -- 5. compare nodes and update xmin,xmax,ymin,ymax
-
-    xmin=ymin= 999999
-    xmax=ymax=-999999
-    insertsql=''
-    renumberednodes={}
-       nodelist=[]
-
-    points.each_index do |i|
-      xs=coord2long(points[i][0],masterscale,baselong)
-      ys=coord2lat(points[i][1],masterscale,basey)
-      xmin=[xs,xmin].min; xmax=[xs,xmax].max
-      ymin=[ys,ymin].min; ymax=[ys,ymax].max
-      node=points[i][2].to_i
-         tagstr=array2tag(points[i][4])
-      tagsql="'"+sqlescape(tagstr)+"'"
-      lat=(ys * 10000000).round
-      long=(xs * 10000000).round
-      tile=QuadTile.tile_for_point(ys, xs)
-
-      # compare node
-      if node<0
-        # new node - create
-               if renumberednodes[node.to_s].nil?
-          newnode=ActiveRecord::Base.connection.insert("INSERT INTO current_nodes (   latitude,longitude,timestamp,user_id,visible,tags,tile) VALUES (           #{lat},#{long},#{db_now},#{uid},1,#{tagsql},#{tile})")
-                  ActiveRecord::Base.connection.insert("INSERT INTO nodes         (id,latitude,longitude,timestamp,user_id,visible,tags,tile) VALUES (#{newnode},#{lat},#{long},#{db_now},#{uid},1,#{tagsql},#{tile})")
-          points[i][2]=newnode
-          nodelist.push(newnode)
-          renumberednodes[node.to_s]=newnode.to_s
-               else
-          points[i][2]=renumberednodes[node.to_s].to_i
-               end
-
-      elsif xc.has_key?(node)
-               nodelist.push(node)
-        # old node from original way - update
-        if (xs!=xc[node] or (ys/0.0000001).round!=(yc[node]/0.0000001).round or tagstr!=tagc[node] or vc[node]==0)
-          ActiveRecord::Base.connection.insert("INSERT INTO nodes (id,latitude,longitude,timestamp,user_id,visible,tags,tile) VALUES (#{node},#{lat},#{long},#{db_now},#{uid},1,#{tagsql},#{tile})")
-          ActiveRecord::Base.connection.update("UPDATE current_nodes SET latitude=#{lat},longitude=#{long},timestamp=#{db_now},user_id=#{uid},tags=#{tagsql},visible=1,tile=#{tile} WHERE id=#{node}")
-        end
-      else
-        # old node, created in another way and now added to this way
-      end
+    # check boundary is sane and area within defined
+    # see /config/application.yml
+    begin
+      check_boundaries(xmin, ymin, xmax, ymax)
+    rescue Exception => err
+      return [-2,"Sorry - I can't get the map for that area."]

     end
 
     end
 

+    nodes_in_area = Node.find_by_area(ymin, xmin, ymax, xmax, :conditions => ["current_ways.visible = ?", false], :include => :ways_via_history)
+    way_ids = nodes_in_area.collect { |node| node.ways_via_history_ids }.flatten.uniq

 
 

-       # -- 6a. delete any nodes not in modified way
+    [0,way_ids]
+  end

 
 

-    createuniquenodes(way,db_uqn,nodelist)     # nodes which appear in this way but no other
+  # Get a way including nodes and tags.
+  # Returns the way id, a Potlatch-style array of points, a hash of tags, and the version number.

 
 

-    sql=<<-EOF
-       INSERT INTO nodes (id,latitude,longitude,timestamp,user_id,visible,tile)  
-       SELECT DISTINCT cn.id,cn.latitude,cn.longitude,#{db_now},#{uid},0,cn.tile
-         FROM current_nodes AS cn,#{db_uqn}
-        WHERE cn.id=node_id
-    EOF
-    ActiveRecord::Base.connection.insert(sql)
+  def getway(wayid) #:doc:
+    if POTLATCH_USE_SQL then
+      points = sql_get_nodes_in_way(wayid)
+      tags = sql_get_tags_in_way(wayid)
+      version = sql_get_way_version(wayid)
+      else
+        # Ideally we would do ":include => :nodes" here but if we do that
+        # then rails only seems to return the first copy of a node when a
+        # way includes a node more than once
+        begin
+          way = Way.find(wayid)
+        rescue ActiveRecord::RecordNotFound
+          return [wayid,[],{}]
+        end

 
 

-    sql=<<-EOF
-      UPDATE current_nodes AS cn, #{db_uqn}
-         SET cn.timestamp=#{db_now},cn.visible=0,cn.user_id=#{uid} 
-       WHERE cn.id=node_id
-    EOF
-    ActiveRecord::Base.connection.update(sql)
+        # check case where way has been deleted or doesn't exist
+        return [wayid,[],{}] if way.nil? or !way.visible

 
 

-       deleteuniquenoderelations(db_uqn,uid,db_now)
-    ActiveRecord::Base.connection.execute("DROP TABLE #{db_uqn}")
+        points = way.nodes.collect do |node|
+        nodetags=node.tags
+        nodetags.delete('created_by')
+        [node.lon, node.lat, node.id, nodetags]
+      end
+      tags = way.tags
+      version = way.version
+    end

 
 

-       #       6b. insert new version of route into way_nodes
+    [wayid, points, tags, version]
+  end

 
 

-    insertsql =''
-    currentsql=''
-    sequence  =1
-    points.each do |p|
-      if insertsql !='' then insertsql +=',' end
-      if currentsql!='' then currentsql+=',' end
-      insertsql +="(#{way},#{p[2]},#{sequence},#{version})"
-      currentsql+="(#{way},#{p[2]},#{sequence})"
-      sequence  +=1
+  # Get an old version of a way, and all constituent nodes.
+  #
+  # For undelete (version<0), always uses the most recent version of each node, 
+  # even if it's moved.  For revert (version >= 0), uses the node in existence 
+  # at the time, generating a new id if it's still visible and has been moved/
+  # retagged.
+  #
+  # Returns:
+  # 0. success code, 
+  # 1. id, 
+  # 2. array of points, 
+  # 3. hash of tags, 
+  # 4. version, 
+  # 5. is this the current, visible version? (boolean)
+
+  def getway_old(id, version) #:doc:
+    if version < 0
+      old_way = OldWay.find(:first, :conditions => ['visible = ? AND id = ?', true, id], :order => 'version DESC')
+      points = old_way.get_nodes_undelete unless old_way.nil?
+    else
+      old_way = OldWay.find(:first, :conditions => ['id = ? AND version = ?', id, version])
+      points = old_way.get_nodes_revert unless old_way.nil?

     end
 
     end
 

-    ActiveRecord::Base.connection.execute("DELETE FROM current_way_nodes WHERE id=#{way}");
-    ActiveRecord::Base.connection.insert( "INSERT INTO         way_nodes (id,node_id,sequence_id,version) VALUES #{insertsql}");
-    ActiveRecord::Base.connection.insert( "INSERT INTO current_way_nodes (id,node_id,sequence_id        ) VALUES #{currentsql}");
-
-    # -- 7. insert new way tags
+    if old_way.nil?
+      return [-1, id, [], {}, -1,0]
+    else
+      curway=Way.find(id)
+      old_way.tags['history'] = "Retrieved from v#{old_way.version}"
+      return [0, id, points, old_way.tags, old_way.version, (curway.version==old_way.version and curway.visible)]
+    end
+  end
+  
+  # Find history of a way. Returns 'way', id, and 
+  # an array of previous versions.
+
+  def getway_history(wayid) #:doc:
+    begin
+      history = Way.find(wayid).old_ways.reverse.collect do |old_way|
+        user_object = old_way.changeset.user
+        user = user_object.data_public? ? user_object.display_name : 'anonymous'
+        uid  = user_object.data_public? ? user_object.id : 0
+        [old_way.version, old_way.timestamp.strftime("%d %b %Y, %H:%M"), old_way.visible ? 1 : 0, user, uid]
+      end

 
 

-    insertsql =''
-    currentsql=''
-    attributes.each do |k,v|
-      if v=='' or v.nil? then next end
-      if v[0,6]=='(type ' then next end
-      if insertsql !='' then insertsql +=',' end
-      if currentsql!='' then currentsql+=',' end
-      insertsql +="(#{way},'"+sqlescape(k.gsub('|',':'))+"','"+sqlescape(v)+"',#{version})"
-      currentsql+="(#{way},'"+sqlescape(k.gsub('|',':'))+"','"+sqlescape(v)+"')"
+      return ['way',wayid,history]
+    rescue ActiveRecord::RecordNotFound
+      return ['way', wayid, []]

     end
     end

+  end

 
 

-    ActiveRecord::Base.connection.execute("DELETE FROM current_way_tags WHERE id=#{way}")
-    if (insertsql !='') then ActiveRecord::Base.connection.insert("INSERT INTO way_tags (id,k,v,version) VALUES #{insertsql}" ) end
-    if (currentsql!='') then ActiveRecord::Base.connection.insert("INSERT INTO current_way_tags (id,k,v) VALUES #{currentsql}") end
+  # Find history of a node. Returns 'node', id, and 
+  # an array of previous versions.

 
 

-    [0,originalway,way,renumberednodes,xmin,xmax,ymin,ymax]
+  def getnode_history(nodeid) #:doc:
+    begin
+         history = Node.find(nodeid).old_nodes.reverse.collect do |old_node|
+        user_object = old_node.changeset.user
+        user = user_object.data_public? ? user_object.display_name : 'anonymous'
+        uid  = user_object.data_public? ? user_object.id : 0
+        [old_node.version, old_node.timestamp.strftime("%d %b %Y, %H:%M"), old_node.visible ? 1 : 0, user, uid]
+      end
+
+      return ['node',nodeid,history]
+    rescue ActiveRecord::RecordNotFound
+      return ['node', nodeid, []]
+    end

   end
 
   end
 

-  # -----      putpoi (user token, id, x,y,tag array,visible,baselong,basey,masterscale)
-  #                    returns current id, new id
-  #                    if new: add new row to current_nodes and nodes
-  #                    if old: add new row to nodes, update current_nodes
-
-  def putpoi(args)
-    usertoken,id,x,y,tags,visible,baselong,basey,masterscale=args
-    uid=getuserid(usertoken)
-    if !uid then return -1,"You are not logged in, so the point could not be saved." end
-
-    db_now='@now'+(rand*100).to_i.to_s+uid.to_s+id.to_i.abs.to_s+Time.new.to_i.to_s    # 'now' variable name, typically 51 chars
-    ActiveRecord::Base.connection.execute("SET #{db_now}=NOW()")
-
-    id=id.to_i
-    visible=visible.to_i
-       if visible==0 then
-               # if deleting, check node hasn't become part of a way 
-               inway=ActiveRecord::Base.connection.select_one("SELECT cw.id FROM current_ways cw,current_way_nodes cwn WHERE cw.id=cwn.id AND cw.visible=1 AND cwn.node_id=#{id} LIMIT 1")
-               unless inway.nil? then return -1,"The point has since become part of a way, so you cannot save it as a POI." end
-               deleteitemrelations(id,'node',uid,db_now)
+  # Find GPS traces with specified name/id.
+  # Returns array listing GPXs, each one comprising id, name and description.
+  
+  def findgpx(searchterm, usertoken)
+    uid = getuserid(usertoken)
+    if !uid then return -1,"You must be logged in to search for GPX traces." end
+
+    gpxs = []
+    if searchterm.to_i>0 then
+      gpx = Trace.find(searchterm.to_i, :conditions => ["visible=? AND (public=? OR user_id=?)",true,true,uid] )
+      if gpx then
+        gpxs.push([gpx.id, gpx.name, gpx.description])
+      end
+    else
+      Trace.find(:all, :limit => 21, :conditions => ["visible=? AND (public=? OR user_id=?) AND MATCH(name) AGAINST (?)",true,true,uid,searchterm] ).each do |gpx|
+      gpxs.push([gpx.id, gpx.name, gpx.description])
+         end

        end
        end

+    gpxs
+  end

 
 

-    x=coord2long(x.to_f,masterscale,baselong)
-    y=coord2lat(y.to_f,masterscale,basey)
-    tagsql="'"+sqlescape(array2tag(tags))+"'"
-    lat=(y * 10000000).round
-    long=(x * 10000000).round
-    tile=QuadTile.tile_for_point(y, x)
-       
-    if (id>0) then
-        ActiveRecord::Base.connection.insert("INSERT INTO nodes (id,latitude,longitude,timestamp,user_id,visible,tags,tile) VALUES (#{id},#{lat},#{long},#{db_now},#{uid},#{visible},#{tagsql},#{tile})");
-        ActiveRecord::Base.connection.update("UPDATE current_nodes SET latitude=#{lat},longitude=#{long},timestamp=#{db_now},user_id=#{uid},visible=#{visible},tags=#{tagsql},tile=#{tile} WHERE id=#{id}");
-        newid=id
-    else
-        newid=ActiveRecord::Base.connection.insert("INSERT INTO current_nodes (latitude,longitude,timestamp,user_id,visible,tags,tile) VALUES (#{lat},#{long},#{db_now},#{uid},#{visible},#{tagsql},#{tile})");
-              ActiveRecord::Base.connection.update("INSERT INTO nodes (id,latitude,longitude,timestamp,user_id,visible,tags,tile) VALUES (#{newid},#{lat},#{long},#{db_now},#{uid},#{visible},#{tagsql},#{tile})");
+  # Get a relation with all tags and members.
+  # Returns:
+  # 0. relation id,
+  # 1. hash of tags,
+  # 2. list of members,
+  # 3. version.
+  
+  def getrelation(relid) #:doc:
+    begin
+      rel = Relation.find(relid)
+    rescue ActiveRecord::RecordNotFound
+      return [relid, {}, []]

     end
     end

-    [0,id,newid]
+
+    return [relid, {}, [], nil] if rel.nil? or !rel.visible
+    [relid, rel.tags, rel.members, rel.version]

   end
 
   end
 

-  # -----      getpoi (id,baselong,basey,masterscale)
-  #                    returns id,x,y,tag array
+  # Find relations with specified name/id.
+  # Returns array of relations, each in same form as getrelation.

   
   

-  def getpoi(args)
-       id,baselong,basey,masterscale=args; id=id.to_i
-       poi=ActiveRecord::Base.connection.select_one("SELECT latitude*0.0000001 AS lat,longitude*0.0000001 AS lng,tags "+
-               "FROM current_nodes WHERE visible=1 AND id=#{id}")
-       if poi.nil? then return [nil,nil,nil,''] end
-       [id,
-        long2coord(poi['lng'].to_f,baselong,masterscale),
-        lat2coord(poi['lat'].to_f,basey,masterscale),
-        tag2array(poi['tags'])]
+  def findrelations(searchterm)
+    rels = []
+    if searchterm.to_i>0 then
+      rel = Relation.find(searchterm.to_i)
+      if rel and rel.visible then
+        rels.push([rel.id, rel.tags, rel.members])
+      end
+    else
+      RelationTag.find(:all, :limit => 11, :conditions => ["match(v) against (?)", searchterm] ).each do |t|
+      if t.relation.visible then
+             rels.push([t.relation.id, t.relation.tags, t.relation.members])
+           end
+         end
+       end
+    rels

   end
 
   end
 

-  # -----      deleteway (user token, way, nodes to keep)
-  #                    returns way ID only
+  # Save a relation.
+  # Returns
+  # 0. 0 (success),
+  # 1. original relation id (unchanged),
+  # 2. new relation id.

 
 

-  def deleteway(args)
-    usertoken,way=args
+  def putrelation(renumberednodes, renumberedways, usertoken, changeset, version, relid, tags, members, visible) #:doc:
+    user = getuserid(usertoken)
+    if !user then return -1,"You are not logged in, so the relation could not be saved." end

 
 

-    RAILS_DEFAULT_LOGGER.info("  Message: deleteway, id=#{way}")
-    uid=getuserid(usertoken)
-    if !uid then return -1,"You are not logged in, so the way could not be deleted." end
+    relid = relid.to_i
+    visible = (visible.to_i != 0)

 
 

-    way=way.to_i
-    db_uqn='unin'+(rand*100).to_i.to_s+uid.to_s+way.to_i.abs.to_s+Time.new.to_i.to_s   # temp uniquenodes table name, typically 51 chars
-    db_now='@now'+(rand*100).to_i.to_s+uid.to_s+way.to_i.abs.to_s+Time.new.to_i.to_s   # 'now' variable name, typically 51 chars
-    ActiveRecord::Base.connection.execute("SET #{db_now}=NOW()")
+    # create a new relation, or find the existing one
+    if relid > 0
+      relation = Relation.find(relid)
+    end
+    # We always need a new node, based on the data that has been sent to us
+    new_relation = Relation.new
+
+    # check the members are all positive, and correctly type
+    typedmembers = []
+    members.each do |m|
+      mid = m[1].to_i
+      if mid < 0
+        mid = renumberednodes[mid] if m[0] == 'node'
+        mid = renumberedways[mid] if m[0] == 'way'
+      end
+      if mid
+        typedmembers << [m[0], mid, m[2]]
+      end
+    end

 
 

-    # - delete any otherwise unused nodes
-  
-    createuniquenodes(way,db_uqn,[])
+    # assign new contents
+    new_relation.members = typedmembers
+    new_relation.tags = tags
+    new_relation.visible = visible
+    new_relation.changeset_id = changeset
+    new_relation.version = version

 
 

-#      unless (preserve.empty?) then
-#              ActiveRecord::Base.connection.execute("DELETE FROM #{db_uqn} WHERE node_id IN ("+preserve.join(',')+")")
-#      end

 
 

-    sql=<<-EOF
-       INSERT INTO nodes (id,latitude,longitude,timestamp,user_id,visible,tile)
-       SELECT DISTINCT cn.id,cn.latitude,cn.longitude,#{db_now},#{uid},0,cn.tile
-         FROM current_nodes AS cn,#{db_uqn}
-        WHERE cn.id=node_id
-    EOF
-    ActiveRecord::Base.connection.insert(sql)
+    if id <= 0
+      # We're creating the node
+      new_relation.create_with_history(user)
+    elsif visible
+      # We're updating the node
+      relation.update_from(new_relation, user)
+    else
+      # We're deleting the node
+      relation.delete_with_history!(new_relation, user)
+    end
+      
+    if id <= 0
+      return [0, relid, new_relation.id, new_relation.version]
+    else
+      return [0, relid, relation.id, relation.version]
+    end
+  rescue OSM::APIChangesetAlreadyClosedError => ex
+    return [-1, "The changeset #{ex.changeset.id} was closed at #{ex.changeset.closed_at}"]
+  rescue OSM::APIVersionMismatchError => ex
+    return [-1, "You have taken too long to edit, please reload the area"]
+  rescue OSM::APIAlreadyDeletedError => ex
+    return [-1, "The object has already been deleted"]
+  rescue OSM::APIError => ex
+    # Some error that we don't specifically catch
+    return [-2, "Something really bad happened :-()"]
+  end

 
 

-    sql=<<-EOF
-      UPDATE current_nodes AS cn, #{db_uqn}
-         SET cn.timestamp=#{db_now},cn.visible=0,cn.user_id=#{uid} 
-       WHERE cn.id=node_id
-    EOF
-    ActiveRecord::Base.connection.update(sql)
+  # Save a way to the database, including all nodes. Any nodes in the previous
+  # version and no longer used are deleted.
+  # 
+  # Returns:
+  # 0. '0' (code for success),
+  # 1. original way id (unchanged),
+  # 2. new way id,
+  # 3. hash of renumbered nodes (old id=>new id),
+  # 4. version

 
 

-       deleteuniquenoderelations(db_uqn,uid,db_now)
-    ActiveRecord::Base.connection.execute("DROP TABLE #{db_uqn}")
+  def putway(renumberednodes, usertoken, changeset, originalway, points, attributes) #:doc:

 
 

-    # - delete way
+    # -- Initialise and carry out checks

        
        

-    ActiveRecord::Base.connection.insert("INSERT INTO ways (id,user_id,timestamp,visible) VALUES (#{way},#{uid},#{db_now},0)")
-    ActiveRecord::Base.connection.update("UPDATE current_ways SET user_id=#{uid},timestamp=#{db_now},visible=0 WHERE id=#{way}")
-    ActiveRecord::Base.connection.execute("DELETE FROM current_way_nodes WHERE id=#{way}")
-    ActiveRecord::Base.connection.execute("DELETE FROM current_way_tags WHERE id=#{way}")
-       deleteitemrelations(way,'way',uid,db_now)
-    [0,way]
-end
+    user = getuser(usertoken)
+    if !user then return -1,"You are not logged in, so the way could not be saved." end

 
 

+    originalway = originalway.to_i

 
 

+    points.each do |a|
+      if a[2] == 0 or a[2].nil? then return -2,"Server error - node with id 0 found in way #{originalway}." end
+      if a[1] == 90 then return -2,"Server error - node with lat -90 found in way #{originalway}." end
+    end

 
 

-# ====================================================================
-# Support functions for remote calls
-
-def readwayquery(id)
-  ActiveRecord::Base.connection.select_all "SELECT latitude*0.0000001 AS latitude,longitude*0.0000001 AS longitude,current_nodes.id,tags "+
-      "    FROM current_way_nodes,current_nodes "+
-      "   WHERE current_way_nodes.id=#{id} "+
-      "     AND current_way_nodes.node_id=current_nodes.id "+
-      "     AND current_nodes.visible=1 "+
-      "   ORDER BY sequence_id"
-end
+    if points.length < 2 then return -2,"Server error - way is only #{points.length} points long." end

 
 

-def getlastversion(id,version)
-  row=ActiveRecord::Base.connection.select_one("SELECT version FROM ways WHERE id=#{id} AND visible=1 ORDER BY version DESC LIMIT 1")
-  row['version']
-end
+    # -- Get unique nodes

 
 

-def readwayquery_old(id,version,historic)
-  # Node handling on undelete (historic=false):
-  # - always use the node specified, even if it's moved
-  
-  # Node handling on revert (historic=true):
-  # - if it's a visible node, use a new node id (i.e. not mucking up the old one)
-  #   which means the SWF needs to allocate new ids
-  # - if it's an invisible node, we can reuse the old node id
-
-  # get node list from specified version of way,
-  # and the _current_ lat/long/tags of each node
-
-  row=ActiveRecord::Base.connection.select_one("SELECT timestamp FROM ways WHERE version=#{version} AND id=#{id}")
-  waytime=row['timestamp']
-
-  sql=<<-EOF
-       SELECT cn.id,visible,latitude*0.0000001 AS latitude,longitude*0.0000001 AS longitude,tags 
-         FROM way_nodes wn,current_nodes cn 
-        WHERE wn.version=#{version} 
-          AND wn.id=#{id} 
-          AND wn.node_id=cn.id 
-        ORDER BY sequence_id
-  EOF
-  rows=ActiveRecord::Base.connection.select_all(sql)
-
-  # if historic (full revert), get the old version of each node,
-  # and use this (though with a new id) if it differs from the current one
-  if historic then
-       rows.each_index do |i|
-         sql=<<-EOF
-         SELECT latitude*0.0000001 AS latitude,longitude*0.0000001 AS longitude,tags 
-           FROM nodes 
-          WHERE id=#{rows[i]['id']} 
-            AND timestamp<="#{waytime}" 
-          ORDER BY timestamp DESC 
-          LIMIT 1
-         EOF
-         row=ActiveRecord::Base.connection.select_one(sql)
-         unless row.nil? then
-           nx=row['longitude'].to_f
-           ny=row['latitude'].to_f
-           if (nx!=rows[i]['longitude'].to_f or ny!=rows[i]['latitude'].to_f or row['tags']!=rows[i]['tags']) then
-                 rows[i]['id']=-1
-                 # This generates a new node id if x/y/tags differ from current node.
-                 # Strictly speaking, it need only do this for uniquenodes, but we're
-                 # not generating uniquenodes for historic ways (yet!).
-           end
-               rows[i]['longitude']=nx
-               rows[i]['latitude' ]=ny
-               rows[i]['tags'     ]=row['tags']
-         end
+    if originalway <= 0
+      uniques = []
+    else
+      way = Way.find(originalway)
+      uniques = way.unshared_node_ids

     end
     end

-  end
-  rows
-end
+    new_way = Way.new

 
 

-def createuniquenodes(way,uqn_name,nodelist)
-       # Find nodes which appear in this way but no others
-       sql=<<-EOF
-       CREATE TEMPORARY TABLE #{uqn_name}
-                                       SELECT a.node_id
-                                         FROM (SELECT DISTINCT node_id FROM current_way_nodes
-                                                       WHERE id=#{way}) a
-                                LEFT JOIN current_way_nodes b
-                                               ON b.node_id=a.node_id
-                                          AND b.id!=#{way}
-                                        WHERE b.node_id IS NULL
-       EOF
-       unless nodelist.empty? then
-         sql+="AND a.node_id NOT IN ("+nodelist.join(',')+")"
-       end
-       ActiveRecord::Base.connection.execute(sql)
-end
+    # -- Compare nodes and save changes to any that have changed

 
 

+    nodes = []

 
 

+    points.each do |n|
+      lon = n[0].to_f
+      lat = n[1].to_f
+      id = n[2].to_i
+      version = n[3].to_i # FIXME which index does the version come in on????
+      savenode = false
+      # We always need a new node if we are saving it
+      new_node = Node.new

 
 

-# ====================================================================
-# Relations handling
-# deleteuniquenoderelations(uqn_name,uid,db_now)
-# deleteitemrelations(way|node,'way'|'node',uid,db_now)

 
 

-def deleteuniquenoderelations(uqn_name,uid,db_now)
-       sql=<<-EOF
-       SELECT node_id,cr.id FROM #{uqn_name},current_relation_members crm,current_relations cr 
-        WHERE crm.member_id=node_id 
-          AND crm.member_type='node' 
-          AND crm.id=cr.id 
-          AND cr.visible=1
-       EOF
+      if renumberednodes[id]
+        id = renumberednodes[id]
+      elsif id <= 0
+        # Create new node
+        savenode = true
+      else
+        # Don't modify this node, make any changes you want to the new_node above
+        node = Node.find(id)
+        nodetags=node.tags
+        nodetags.delete('created_by')
+        if !fpcomp(lat, node.lat) or !fpcomp(lon, node.lon) or
+           n[4] != nodetags or !node.visible?
+          savenode = true
+        end
+      end

 
 

-       relnodes=ActiveRecord::Base.connection.select_all(sql)
-       relnodes.each do |a|
-               removefromrelation(a['node_id'],'node',a['id'],uid,db_now)
-       end
-end
+      if savenode
+        new_node.changeset_id = changeset
+        new_node.lat = lat
+        new_node.lon = lon
+        new_node.tags = n[4]
+        new_node.visible = true
+        new_node.version = version
+        if id <= 0
+          # We're creating the node
+          new_node.create_with_history(user)
+        else
+          # We're updating the node (no delete here)
+          node.update_from(new_node, user)
+        end

 
 

-def deleteitemrelations(objid,type,uid,db_now)
-       sql=<<-EOF
-       SELECT cr.id FROM current_relation_members crm,current_relations cr 
-        WHERE crm.member_id=#{objid} 
-          AND crm.member_type='#{type}' 
-          AND crm.id=cr.id 
-          AND cr.visible=1
-       EOF
-       
-       relways=ActiveRecord::Base.connection.select_all(sql)
-       relways.each do |a|
-               removefromrelation(objid,type,a['id'],uid,db_now)
-       end
-end
+        if id != node.id
+          renumberednodes[id] = node.id
+          id = node.id
+        end
+      end
+
+      uniques = uniques - [id]
+      nodes.push(id)
+    end

 
 

-def removefromrelation(objid,type,relation,uid,db_now)
-       rver=ActiveRecord::Base.connection.insert("INSERT INTO relations (id,user_id,timestamp,visible) VALUES (#{relation},#{uid},#{db_now},1)")
-
-       tagsql=<<-EOF
-       INSERT INTO relation_tags (id,k,v,version) 
-       SELECT id,k,v,#{rver} FROM current_relation_tags 
-        WHERE id=#{relation} 
-       EOF
-       ActiveRecord::Base.connection.insert(tagsql)
-
-       membersql=<<-EOF
-       INSERT INTO relation_members (id,member_type,member_id,member_role,version) 
-       SELECT id,member_type,member_id,member_role,#{rver} FROM current_relation_members 
-        WHERE id=#{relation} 
-          AND (member_id!=#{objid} OR member_type!='#{type}')
-       EOF
-       ActiveRecord::Base.connection.insert(membersql)
+    # -- Delete any unique nodes

        
        

-       ActiveRecord::Base.connection.update("UPDATE current_relations SET user_id=#{uid},timestamp=#{db_now} WHERE id=#{relation}")
-       ActiveRecord::Base.connection.execute("DELETE FROM current_relation_members WHERE id=#{relation} AND member_type='#{type}' AND member_id=#{objid}")
-end
+    uniques.each do |n|
+      deleteitemrelations(n, 'node')
+
+      node = Node.find(n)
+      new_node = Node.new
+      new_node.changeset_id = changeset
+      new_node.version = version
+      node.delete_with_history!(new_node, user)
+    end

 
 

+    # -- Save revised way

 
 

-def sqlescape(a)
-  a.gsub(/[\000-\037]/,"").gsub("'","''").gsub(92.chr,92.chr+92.chr)
-end
+    if way.tags!=attributes or way.nds!=nodes or !way.visible?
+      new_way = Way.new
+      new_way.tags = attributes
+      new_way.nds = nodes
+      new_way.changeset_id = changeset
+      new_way.version = version
+      way.update_from(new_way, user)
+    end

 
 

-def tag2array(a)
-  tags={}
-  a.gsub(';;;','#%').split(';').each do |b|
-    b.gsub!('#%',';;;')
-    b.gsub!('===','#%')
-    k,v=b.split('=')
-    if k.nil? then k='' end
-    if v.nil? then v='' end
-    tags[k.gsub('#%','=').gsub(':','|')]=v.gsub('#%','=')
+    [0, originalway, way.id, renumberednodes, way.version]

   end
   end

-  tags
-end

 
 

-def array2tag(a)
-  str=''
-  a.each do |k,v|
-    if v=='' then next end
-    if v[0,6]=='(type ' then next end
-    if str!='' then str+=';' end
-    str+=k.gsub(';',';;;').gsub('=','===').gsub('|',':')+'='+v.gsub(';',';;;').gsub('=','===')
-  end
-  str
-end
+  # Save POI to the database.
+  # Refuses save if the node has since become part of a way.
+  # Returns:
+  # 0. 0 (success),
+  # 1. original node id (unchanged),
+  # 2. new node id,
+  # 3. version.

 
 

-def getuserid(token)
-  if (token =~ /^(.+)\+(.+)$/) then
-    user = User.authenticate(:username => $1, :password => $2)
-  else
-    user = User.authenticate(:token => token)
-  end
+  def putpoi(usertoken, changeset, version, id, lon, lat, tags, visible) #:doc:
+    user = getuser(usertoken)
+    if !user then return -1,"You are not logged in, so the point could not be saved." end

 
 

-  return user ? user.id : nil;
-end
+    id = id.to_i
+    visible = (visible.to_i == 1)

 
 

+    if id > 0 then
+      node = Node.find(id)

 
 

+      if !visible then
+        unless node.ways.empty? then return -1,"The point has since become part of a way, so you cannot save it as a POI." end
+        deleteitemrelations(id, 'node')
+      end
+    end
+    # We always need a new node, based on the data that has been sent to us
+    new_node = Node.new
+
+    new_node.changeset_id = changeset
+    new_node.version = version
+    new_node.lat = lat
+    new_node.lon = lon
+    new_node.tags = tags
+    new_node.visible = visible
+    if id <= 0 
+      # We're creating the node
+      new_node.create_with_history(user)
+    elsif visible
+      # We're updating the node
+      node.update_from(new_node, user)
+    else
+      # We're deleting the node
+      node.delete_with_history!(new_node, user)
+    end

 
 

-# ====================================================================
-# AMF read subroutines
+    if id <= 0
+      return [0, id, new_node.id, new_node.version]
+    else
+      return [0, id, node.id, node.version]
+    end
+  end

 
 

-# -----        getint          return two-byte integer
-# -----        getlong         return four-byte long
-# -----        getstring       return string with two-byte length
-# ----- getdouble      return eight-byte double-precision float
-# ----- getobject      return object/hash
-# ----- getarray       return numeric array
+  # Read POI from database
+  # (only called on revert: POIs are usually read by whichways).
+  #
+  # Returns array of id, long, lat, hash of tags, version.

 
 

-def getint(s)
-  s.getc*256+s.getc
-end
+  def getpoi(id,version) #:doc:
+    if version>0 then
+        n = OldNode.find(id, :conditions=>['version=?',version])
+    else
+      n = Node.find(id)
+    end

 
 

-def getlong(s)
-  ((s.getc*256+s.getc)*256+s.getc)*256+s.getc
-end
+    if n
+      return [n.id, n.lon, n.lat, n.tags, n.version]
+    else
+      return [nil, nil, nil, {}, nil]
+    end
+  end

 
 

-def getstring(s)
-  len=s.getc*256+s.getc
-  s.read(len)
-end
+  # Delete way and all constituent nodes. Also removes from any relations.
+  # Returns 0 (success), unchanged way id.

 
 

-def getdouble(s)
-  a=s.read(8).unpack('G')                      # G big-endian, E little-endian
-  a[0]
-end
+  def deleteway(usertoken, changeset_id, way_id) #:doc:
+    if !getuserid(usertoken) then return -1,"You are not logged in, so the way could not be deleted." end

 
 

-def getarray(s)
-  len=getlong(s)
-  arr=[]
-  for i in (0..len-1)
-    arr[i]=getvalue(s)
-  end
-  arr
-end
+    way_id = way_id.to_i

 
 

-def getobject(s)
-  arr={}
-  while (key=getstring(s))
-    if (key=='') then break end
-    arr[key]=getvalue(s)
-  end
-  s.getc               # skip the 9 'end of object' value
-  arr
-end
+    # FIXME: would be good not to make two history entries when removing
+    #           two nodes from the same relation
+    way = Way.find(way_id)
+    way.unshared_node_ids.each do |n|
+      deleteitemrelations(n, 'node')
+    end
+    deleteitemrelations(way_id, 'way')

 
 

-# -----        getvalue        parse and get value
-
-def getvalue(s)
-  case s.getc
-       when 0; return getdouble(s)                     # number
-       when 1; return s.getc                           # boolean
-       when 2; return getstring(s)                     # string
-       when 3; return getobject(s)                     # object/hash
-       when 5; return nil                                      # null
-       when 6; return nil                                      # undefined
-       when 8; s.read(4)                                       # mixedArray
-                       return getobject(s)                     #  |
-       when 10;return getarray(s)                      # array
-       else;   return nil                                      # error
+    way.delete_with_relations_and_nodes_and_history(changeset_id.to_i)
+
+    [0, way_id]

   end
   end

-end

 
 

-# ====================================================================
-# AMF write subroutines

 
 

-# -----        putdata         envelope data into AMF writeable form
-# -----        encodevalue     pack variables as AMF
+  # ====================================================================
+  # Support functions

 
 

-def putdata(index,n)
-  d =encodestring(index+"/onResult")
-  d+=encodestring("null")
-  d+=[-1].pack("N")
-  d+=encodevalue(n)
-end
+  # Remove a node or way from all relations
+
+  def deleteitemrelations(objid, type) #:doc:
+    relations = RelationMember.find(:all, 
+                                                                       :conditions => ['member_type = ? and member_id = ?', type, objid], 
+                                                                       :include => :relation).collect { |rm| rm.relation }.uniq

 
 

-def encodevalue(n)
-  case n.class.to_s
-  when 'Array'
-    a=10.chr+encodelong(n.length)
-    n.each do |b|
-      a+=encodevalue(b)
-    end
-    a
-  when 'Hash'
-    a=3.chr
-    n.each do |k,v|
-      a+=encodestring(k)+encodevalue(v)
-    end
-    a+0.chr+0.chr+9.chr
-  when 'String'
-    2.chr+encodestring(n)
-  when 'Bignum','Fixnum','Float'
-    0.chr+encodedouble(n)
-  when 'NilClass'
-    5.chr
-  else
-    RAILS_DEFAULT_LOGGER.error("Unexpected Ruby type for AMF conversion: "+n.class.to_s)
+    relations.each do |rel|
+      rel.members.delete_if { |x| x[0] == type and x[1] == objid }
+      rel.save_with_history!
+    end

   end
   end

-end

 
 

-# -----        encodestring    encode string with two-byte length
-# -----        encodedouble    encode number as eight-byte double precision float
-# -----        encodelong              encode number as four-byte long
+  # Break out node tags into a hash
+  # (should become obsolete as of API 0.6)

 
 

-def encodestring(n)
-  a,b=n.size.divmod(256)
-  a.chr+b.chr+n
-end
+  def tagstring_to_hash(a) #:doc:
+    tags={}
+    Tags.split(a) do |k, v|
+      tags[k]=v
+    end
+    tags
+  end

 
 

-def encodedouble(n)
-  [n].pack('G')
-end
+  # Authenticate token
+  # (can also be of form user:pass)
+  # When we are writing to the api, we need the actual user model, 
+  # not just the id, hence this abstraction

 
 

-def encodelong(n)
-  [n].pack('N')
-end
+  def getuser(token) #:doc:
+    if (token =~ /^(.+)\:(.+)$/) then
+      user = User.authenticate(:username => $1, :password => $2)
+    else
+      user = User.authenticate(:token => token)
+    end
+    return user
+  end
+  
+  def getuserid(token)
+    user = getuser(token)
+    return user ? user.id : nil;
+  end

 
 

-# ====================================================================
-# Co-ordinate conversion
+  # Compare two floating-point numbers to within 0.0000001

 
 

-def lat2coord(a,basey,masterscale)
-  -(lat2y(a)-basey)*masterscale+250
-end
+  def fpcomp(a,b) #:doc:
+    return ((a/0.0000001).round==(b/0.0000001).round)
+  end

 
 

-def long2coord(a,baselong,masterscale)
-  (a-baselong)*masterscale+350
-end
+  # Send AMF response
+  
+  def sendresponse(results)
+    a,b=results.length.divmod(256)
+    render :content_type => "application/x-amf", :text => proc { |response, output| 
+      # ** move amf writing loop into here - 
+      # basically we read the messages in first (into an array of some sort),
+      # then iterate through that array within here, and do all the AMF writing
+      output.write 0.chr+0.chr+0.chr+0.chr+a.chr+b.chr
+      results.each do |k,v|
+        output.write(v)
+      end
+    }
+  end

 
 

-def lat2y(a)
-  180/Math::PI * Math.log(Math.tan(Math::PI/4+a*(Math::PI/180)/2))
-end

 
 

-def coord2lat(a,masterscale,basey)
-  y2lat((a-250)/-masterscale+basey)
-end
+  # ====================================================================
+  # Alternative SQL queries for getway/whichways

 
 

-def coord2long(a,masterscale,baselong)
-  (a-350)/masterscale+baselong
-end
+  def sql_find_ways_in_area(xmin,ymin,xmax,ymax)
+    sql=<<-EOF
+    SELECT DISTINCT current_ways.id AS wayid,current_ways.version AS version
+      FROM current_way_nodes
+    INNER JOIN current_nodes ON current_nodes.id=current_way_nodes.node_id
+    INNER JOIN current_ways  ON current_ways.id =current_way_nodes.id
+       WHERE current_nodes.visible=TRUE 
+       AND current_ways.visible=TRUE 
+       AND #{OSM.sql_for_area(ymin, xmin, ymax, xmax, "current_nodes.")}
+    EOF
+    return ActiveRecord::Base.connection.select_all(sql).collect { |a| [a['wayid'].to_i,a['version'].to_i] }
+  end
+       
+  def sql_find_pois_in_area(xmin,ymin,xmax,ymax)
+    pois=[]
+    sql=<<-EOF
+                 SELECT current_nodes.id,current_nodes.latitude*0.0000001 AS lat,current_nodes.longitude*0.0000001 AS lon,current_nodes.version 
+                       FROM current_nodes 
+       LEFT OUTER JOIN current_way_nodes cwn ON cwn.node_id=current_nodes.id 
+                  WHERE current_nodes.visible=TRUE
+                        AND cwn.id IS NULL
+                        AND #{OSM.sql_for_area(ymin, xmin, ymax, xmax, "current_nodes.")}
+    EOF
+    ActiveRecord::Base.connection.select_all(sql).each do |row|
+      poitags={}
+      ActiveRecord::Base.connection.select_all("SELECT k,v FROM current_node_tags WHERE id=#{row['id']}").each do |n|
+        poitags[n['k']]=n['v']
+      end
+      pois << [row['id'].to_i, row['lon'].to_f, row['lat'].to_f, poitags, row['version'].to_i]
+    end
+    pois
+  end
+       
+  def sql_find_relations_in_area_and_ways(xmin,ymin,xmax,ymax,way_ids)
+    # ** It would be more Potlatchy to get relations for nodes within ways
+    #    during 'getway', not here
+    sql=<<-EOF
+      SELECT DISTINCT cr.id AS relid,cr.version AS version 
+      FROM current_relations cr
+      INNER JOIN current_relation_members crm ON crm.id=cr.id 
+      INNER JOIN current_nodes cn ON crm.member_id=cn.id AND crm.member_type='node' 
+       WHERE #{OSM.sql_for_area(ymin, xmin, ymax, xmax, "cn.")}
+      EOF
+    unless way_ids.empty?
+      sql+=<<-EOF
+       UNION
+        SELECT DISTINCT cr.id AS relid,cr.version AS version
+        FROM current_relations cr
+        INNER JOIN current_relation_members crm ON crm.id=cr.id
+         WHERE crm.member_type='way' 
+         AND crm.member_id IN (#{way_ids.join(',')})
+        EOF
+    end
+    return ActiveRecord::Base.connection.select_all(sql).collect { |a| [a['relid'].to_i,a['version'].to_i] }
+  end
+       
+  def sql_get_nodes_in_way(wayid)
+    points=[]
+    sql=<<-EOF
+      SELECT latitude*0.0000001 AS lat,longitude*0.0000001 AS lon,current_nodes.id 
+      FROM current_way_nodes,current_nodes 
+       WHERE current_way_nodes.id=#{wayid.to_i} 
+                  AND current_way_nodes.node_id=current_nodes.id 
+                  AND current_nodes.visible=TRUE
+      ORDER BY sequence_id
+         EOF
+    ActiveRecord::Base.connection.select_all(sql).each do |row|
+      nodetags={}
+      ActiveRecord::Base.connection.select_all("SELECT k,v FROM current_node_tags WHERE id=#{row['id']}").each do |n|
+        nodetags[n['k']]=n['v']
+      end
+      nodetags.delete('created_by')
+      points << [row['lon'].to_f,row['lat'].to_f,row['id'].to_i,nodetags]
+    end
+    points
+  end
+       
+  def sql_get_tags_in_way(wayid)
+    tags={}
+    ActiveRecord::Base.connection.select_all("SELECT k,v FROM current_way_tags WHERE id=#{wayid.to_i}").each do |row|
+      tags[row['k']]=row['v']
+    end
+    tags
+  end

 
 

-def y2lat(a)
-  180/Math::PI * (2*Math.atan(Math.exp(a*Math::PI/180))-Math::PI/2)
+  def sql_get_way_version(wayid)
+    ActiveRecord::Base.connection.select_one("SELECT version FROM current_ways WHERE id=#{wayid.to_i}")
+  end

 end
 
 end
 

-end