X-Git-Url: https://git.openstreetmap.org./rails.git/blobdiff_plain/276f165f3faca4913b63126de271530d2992a0ba..b7b2b502cf2b119208e3c1f79e4a4e38cc0edcc5:/app/controllers/amf_controller.rb?ds=inline

diff --git a/app/controllers/amf_controller.rb b/app/controllers/amf_controller.rb
index ac0809219..6e1b364d4 100644
--- a/app/controllers/amf_controller.rb
+++ b/app/controllers/amf_controller.rb
@@ -1,758 +1,782 @@
-# AMF Controller is a semi-standalone API for Flash clients, particularly Potlatch.
-# All interaction between Potlatch (as a .SWF application) and the 
+# 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).
 #
-# See Also Potlatch::Potlatch and Potlatch::AMF
+# Helper functions are in /lib/potlatch.
 #
-# Public domain.
-# editions Systeme D / Richard Fairhurst 2004-2008
+# Author::	editions Systeme D / Richard Fairhurst 2004-2008
+# Licence::	public domain.
 #
-# All in/out parameters are floats unless explicitly stated.
+# == 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 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]}")
+# To write to the Rails log, use RAILS_DEFAULT_LOGGER.info("message").
+
 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
 
-  # Main AMF handler. Tha talk method takes in AMF, figures out what to do and dispatched to the appropriate private method
-  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
-    renumberednodes={}							# Shared across repeated putways
-
-    # -------------
-    # Parse request
-
-    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
-
-    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 '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))
-      when 'getway_old';		results[index]=AMF.putdata(index,getway_old(args))
-      when 'getway_history';	results[index]=AMF.putdata(index,getway_history(args))
-      when 'putway';			r=putway(args,renumberednodes)
-        renumberednodes=r[3]
-        results[index]=AMF.putdata(index,r)
-      when 'deleteway';			results[index]=AMF.putdata(index,deleteway(args))
-      when 'putpoi';			results[index]=AMF.putdata(index,putpoi(args))
-      when 'getpoi';			results[index]=AMF.putdata(index,getpoi(args))
-      end
-    end
-
-    # ------------------
-    # Write out response
+  # 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
+  
+  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
+
+	# Parse request
+
+	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
+
+	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
+		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
+    logger.info("encoding AMF results")
+    sendresponse(results)
+  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")
+  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
+
+	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]
+									  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';				results[index]=AMF.putdata(index,putpoi(*args))
+		when 'startchangeset';		results[index]=AMF.putdata(index,startchangeset(*args))
+	  end
+	end
+    sendresponse(results)
   end
 
   private
 
-  # Return presets (default tags and crap) to potlatch.
-  # Uses POTLATCH_PRESETS global, set up in OSM::Potlatch
-  def getpresets #:doc:
-    return POTLATCH_PRESETS
+  # Start new changeset
+  
+  def startchangeset(usertoken, cstags, closeid, closecomment)
+	uid = getuserid(usertoken)
+	if !uid 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.open = false
+	  if closecomment.empty?
+		cs.save!
+	  else
+	    cs.tags['comment']=closecomment
+	    cs.save_with_tags!
+	  end
+	end
+	
+	# open a new changeset
+	cs = Changeset.new
+	cs.tags = cstags
+	cs.user_id = uid
+	cs.created_at = Time.now
+	cs.save_with_tags!
+	return [0,cs.id]
   end
 
-  # ----- whichways
-  # Find all the way ids and nodes (including tags and projected lat/lng) which aren't part of those ways in an are
-  # 
-  # The argument is an array containing the following, in order:
-  # 0. minimum longitude
-  # 1. minimum latitude
-  # 2. maximum longitude
-  # 3. maximum latitude
-  # 4. baselong, 5. basey, 6. masterscale as above
-  def whichways(args) #:doc:
-    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}")
-
-    # find the way ids in an area
-    nodes_in_area = Node.find_by_area(ymin, xmin, ymax, xmax, :conditions => "current_nodes.visible = 1", :include => :ways)
-    way_ids = nodes_in_area.collect { |node| node.way_ids }.flatten.uniq
-
-    # 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_potlatch(baselong,masterscale), n.lat_potlatch(basey,masterscale), n.tags_as_hash] }
-
-    [way_ids,points]
-  end
+  # Return presets (default tags, localisation etc.):
+  # uses POTLATCH_PRESETS global, set up in OSM::Potlatch.
 
-  # ----- whichways_deleted
-  #		  return array of deleted ways in current bounding box
-  #		  in:	as whichways
-  #		  does: finds all deleted ways with a deleted node in bounding box
-  #		  out:	[0] array of way ids
-  def whichways_deleted(args) #:doc:
-    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
 
-  # ----- getway
-  # Get a way with all of it's nodes and tags
-  # The input is an array with the following components, in order:
-  # 0. wayid - the ID of the way to get
-  # 1. baselong - origin of SWF map (longitude)
-  # 2. basey - origin of SWF map (latitude)
-  # 3. masterscale - SWF map scale
-  #
-  # The output is an array which contains all the nodes (with projected 
-  # latitude and longitude) and tags for a way (and all the nodes tags). 
-  # It also has the way's unprojected (WGS84) bbox.
-  #
-  # FIXME: The server really shouldn't be figuring out a ways bounding box and doing projection for potlatch
-  # FIXME: the argument splitting should be done in the 'talk' method, not here
-  def getway(args) #:doc:
-    wayid,baselong,basey,masterscale = args
-    wayid = wayid.to_i
-
-    RAILS_DEFAULT_LOGGER.info("  Message: getway, id=#{wayid}")
-
-    # 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
-    way = Way.find(wayid)
-
-    long_array = []
-    lat_array = []
-    points = []
-
-    way.nodes.each do |node|
-      projected_longitude = node.lon_potlatch(baselong,masterscale) # do projection for potlatch
-      projected_latitude = node.lat_potlatch(basey,masterscale)
-      id = node.id
-      tags_hash = node.tags_as_hash
-
-      points << [projected_longitude, projected_latitude, id, nil, tags_hash]
-      long_array << projected_longitude
-      lat_array << projected_latitude
+  # 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
 
-    [wayid,points,way.tags,long_array.min,long_array.max,lat_array.min,lat_array.max]
+	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
+
+	[0,ways, points, relations]
   end
 
-  # ----- getway_old
-  #		  returns old version of way
-  #		  in:	[0] way id,
-  #				[1] way version to get (or -1 for "last deleted version")
-  #				[2] baselong, [3] basey, [4] masterscale
-  #		  does:	gets old version of way and all constituent nodes
-  #				for undelete, always uses the most recent version of each node
-  #				  (even if it's moved)
-  #				for revert, uses the historic version of each node, but if that node is
-  #				  still visible and has been changed since, generates a new node id
-  #		  out:	[0] 0 (code for success), [1] SWF object name,
-  #				[2] array of points (as getway _except_ [3] is node.visible?, 0 or 1),
-  #				[4] xmin, [5] xmax, [6] ymin, [7] ymax (unprojected bbox),
-  #				[8] way version
-  def getway_old(args) #:doc:
-    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
-
-    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,wayid,points,attributes,xmin,xmax,ymin,ymax,version]
-  end
+  # Find deleted ways in current bounding box (similar to whichways, but ways
+  # with a deleted node only - not POIs or relations).
 
-  # ----- getway_history
-  #		  find history of a way
-  #		  in:	[0] way id
-  #		  does:	finds history of a way
-  #		  out:	[0] array of previous versions (where each is
-  #					[0] version, [1] db timestamp (string),
-  #					[2] visible 0 or 1,
-  #					[3] username or 'anonymous' (string))
-  def getway_history(args) #:doc:
-    wayid=args[0]
-    history=[]
-    sql=<<-EOF
-  SELECT version,timestamp,visible,display_name,data_public
-    FROM ways,users
-   WHERE ways.id=#{wayid}
-     AND ways.user_id=users.id
-     AND ways.visible=1
-   ORDER BY version DESC
-  EOF
-    histlist=ActiveRecord::Base.connection.select_all(sql)
-    histlist.each { |row|
-      if row['data_public'].to_i==1 then user=row['display_name'] else user='anonymous' end
-      history<<[row['version'],row['timestamp'],row['visible'],user]
-    }
-    [history]
-  end
+  def whichways_deleted(xmin, ymin, xmax, ymax) #:doc:
+	xmin -= 0.01; ymin -= 0.01
+	xmax += 0.01; ymax += 0.01
 
-  # ----- putway
-  #		  saves a way to the database
-  #		  in:	[0] user token (string),
-  #				[1] original way id (may be negative), 
-  #				[2] array of points (as getway/getway_old),
-  #				[3] hash of way tags,
-  #				[4] original way version (0 if not a reverted/undeleted way),
-  #				[5] baselong, [6] basey, [7] masterscale
-  #		  does: saves way to the database
-  #				all constituent nodes are created/updated as necessary
-  #				(or deleted if they were in the old version and are otherwise unused)
-  #		  out:	[0] 0 (code for success), [1] original way id (unchanged),
-  #				[2] new way id, [3] hash of renumbered nodes (old id=>new id),
-  #				[4] xmin, [5] xmax, [6] ymin, [7] ymax (unprojected bbox)
-  def putway(args,renumberednodes) #:doc:
-    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}")
-
-    # -- 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
+    # 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
 
-    # -- 3.	read original way into memory
-
-    xc={}; yc={}; tagc={}; vc={}
-    if originalway>0
-      way=originalway
-      if oldversion==0 then r=readwayquery(way,false)
-      else r=readwayquery_old(way,oldversion,true) end
-      r.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
-      }
-      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
+	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
 
-    # -- 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=''
-    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/0.0000001).round!=(xc[node]/0.0000001).round 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
-    end
+	[0,way_ids]
+  end
 
-    # -- 6a. delete any nodes not in modified way
-
-    createuniquenodes(way,db_uqn,nodelist)	# nodes which appear in this way but no other
-
-    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)
-
-    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)
-
-    deleteuniquenoderelations(db_uqn,uid,db_now)
-    ActiveRecord::Base.connection.execute("DROP TEMPORARY TABLE #{db_uqn}")
-
-    #	6b. insert new version of route into way_nodes
-
-    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
-    end
+  # 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.
+
+  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
 
-    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
-
-    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)+"')"
-    end
+      # check case where way has been deleted or doesn't exist
+      return [wayid,[],{}] if way.nil? or !way.visible
 
-    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
+	  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
 
-    [0,originalway,way,renumberednodes,xmin,xmax,ymin,ymax]
+	[wayid, points, tags, version]
   end
 
-  # ----- putpoi
-  #		  save POI to the database
-  #		  in:	[0] user token (string),
-  #				[1] original node id (may be negative),
-  #			  	[2] projected longitude, [3] projected latitude,
-  #				[4] hash of tags, [5] visible (0 to delete, 1 otherwise), 
-  #				[6] baselong, [7] basey, [8] masterscale
-  #		  does:	saves POI node to the database
-  #				refuses save if the node has since become part of a way
-  #		  out:	[0] 0 (success), [1] original node id (unchanged),
-  #				[2] new node id
-  def putpoi(args) #:doc:
-    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)
+  # 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
+
+    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
+
+	  return ['way',wayid,history]
+    rescue ActiveRecord::RecordNotFound
+      return ['way', wayid, []]
     end
+  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})");
+  # Find history of a node. Returns 'node', id, and 
+  # an array of previous versions.
+
+  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
-    [0,id,newid]
   end
 
-  # ----- getpoi
-  # read POI from database
-  #		  (only called on revert: POIs are usually read by whichways)
-  #		  in:	[0] node id, [1] baselong, [2] basey, [3] masterscale
-  #		  does: reads POI
-  #		  out:	[0] id (unchanged), [1] projected long, [2] projected lat,
-  #				[3] hash of tags
-  def getpoi(args) #:doc:
-    id,baselong,basey,masterscale = args
-    
-    n = Node.find(id.to_i)
-    if n
-      return [n.id, n.long_potlatch(baselong,masterscale), n.lat_potlatch(basey,masterscale), n.tags_as_hash]
-    else
-      return [nil,nil,nil,'']
+  # 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
+	gpxs
+  end
+
+  # 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
+
+    return [relid, {}, [], nil] if rel.nil? or !rel.visible
+	[relid, rel.tags, rel.members, rel.version]
   end
 
-  # ----- deleteway
-  #		  delete way and constituent nodes from database
-  #		  in:	[0] user token (string), [1] way id
-  #		  does: deletes way from db and any constituent nodes not used elsewhere
-  #				also removes ways/nodes from any relations they're in
-  #		  out:	[0] 0 (success), [1] way id (unchanged)
-  def deleteway(args) #:doc:
-
-    usertoken,way=args
-
-    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
-
-    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()")
-
-    # - delete any otherwise unused nodes
-
-    createuniquenodes(way,db_uqn,[])
-
-    #	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)
-
-    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)
-
-    deleteuniquenoderelations(db_uqn,uid,db_now)
-    ActiveRecord::Base.connection.execute("DROP TEMPORARY TABLE #{db_uqn}")
-
-    # - delete way
-
-    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]
+  # Find relations with specified name/id.
+  # Returns array of relations, each in same form as getrelation.
+  
+  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
 
-  def readwayquery(id,insistonvisible) #:doc:
-    sql=<<-EOF
-    SELECT latitude*0.0000001 AS latitude,longitude*0.0000001 AS longitude,current_nodes.id,tags,visible 
-      FROM current_way_nodes,current_nodes 
-     WHERE current_way_nodes.id=#{id} 
-       AND current_way_nodes.node_id=current_nodes.id 
-  EOF
-    if insistonvisible then sql+=" AND current_nodes.visible=1 " end
-    sql+=" ORDER BY sequence_id"
-    ActiveRecord::Base.connection.select_all(sql)
+  # Save a relation.
+  # Returns
+  # 0. 0 (success),
+  # 1. original relation id (unchanged),
+  # 2. new relation id.
+
+  def putrelation(renumberednodes, renumberedways, usertoken, changeset, relid, tags, members, visible) #:doc:
+	uid = getuserid(usertoken)
+	if !uid then return -1,"You are not logged in, so the relation could not be saved." end
+
+	relid = relid.to_i
+	visible = (visible.to_i != 0)
+
+	# create a new relation, or find the existing one
+	if relid <= 0
+	  rel = Relation.new
+	  rel.version = 0
+	else
+	  rel = Relation.find(relid)
+	end
+
+	# 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
+
+	# assign new contents
+	rel.members = typedmembers
+	rel.tags = tags
+	rel.visible = visible
+	rel.changeset_id = changeset
+
+	# check it then save it
+	# BUG: the following is commented out because it always fails on my
+	#  install. I think it's a Rails bug.
+
+	#if !rel.preconditions_ok?
+	#  return -2, "Relation preconditions failed"
+	#else
+	  rel.save_with_history!
+	#end
+
+	[0, relid, rel.id]
   end
 
-  # Get the latest version id of a way
-  def getlastversion(id,version) #:doc:
-    old_way = OldWay.find(:first, :conditions => ['id = ?' , id], :order => 'version DESC')
-    old_way.version
+  # 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
+
+  def putway(renumberednodes, usertoken, changeset, originalway, points, attributes) #:doc:
+
+	# -- Initialise and carry out checks
+	
+	uid = getuserid(usertoken)
+	if !uid 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
+
+	if points.length < 2 then return -2,"Server error - way is only #{points.length} points long." end
+
+	# -- Get unique nodes
+
+	if originalway < 0
+	  way = Way.new
+	  way.version = 0	# otherwise +=1 breaks
+	  uniques = []
+	else
+	  way = Way.find(originalway)
+	  uniques = way.unshared_node_ids
+	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
+	  savenode = false
+
+	  if renumberednodes[id]
+	    id = renumberednodes[id]
+	  elsif id < 0
+		# Create new node
+		node = Node.new
+		node.version = 0	# otherwise +=1 breaks
+		savenode = true
+	  else
+		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
+
+	  if savenode
+		node.changeset_id = changeset
+	    node.lat = lat
+        node.lon = lon
+	    node.tags = n[4]
+	    node.visible = true
+	    node.save_with_history!
+
+		if id != node.id
+		  renumberednodes[id] = node.id
+		  id = node.id
+	    end
+	  end
+
+	  uniques = uniques - [id]
+	  nodes.push(id)
+	end
+
+	# -- Delete any unique nodes
+	
+	uniques.each do |n|
+	  deleteitemrelations(n, 'node')
+
+	  node = Node.find(n)
+	  node.changeset_id = changeset
+	  node.visible = false
+	  node.save_with_history!
+	end
+
+	# -- Save revised way
+
+	if way.tags!=attributes or way.nds!=nodes or !way.visible?
+	  way.tags = attributes
+	  way.nds = nodes
+	  way.changeset_id = changeset
+	  way.visible = true
+	  way.save_with_history!
+	end
+
+	[0, originalway, way.id, renumberednodes, way.version]
   end
 
-  def readwayquery_old(id,version,historic) #:doc:
-    # 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
-    # - if it's in another way now, generate a new id
-    # - if it's not in another way, use the old ID
-    if historic then
-      rows.each_index do |i|
-        sql=<<-EOF
-    SELECT latitude*0.0000001 AS latitude,longitude*0.0000001 AS longitude,tags,cwn.id AS currentway 
-      FROM nodes n
-   LEFT JOIN current_way_nodes cwn
-      ON cwn.node_id=n.id
-     WHERE n.id=#{rows[i]['id']} 
-       AND n.timestamp<="#{waytime}" 
-     AND cwn.id!=#{id} 
-     ORDER BY n.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 (row['currentway'] && (nx!=rows[i]['longitude'].to_f or ny!=rows[i]['latitude'].to_f or row['tags']!=rows[i]['tags'])) then rows[i]['id']=-1 end
-          rows[i]['longitude']=nx
-          rows[i]['latitude' ]=ny
-          rows[i]['tags'     ]=row['tags']
-        end
-      end
-    end
-    rows
+  # 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 putpoi(usertoken, changeset, id, lon, lat, tags, visible) #:doc:
+	uid = getuserid(usertoken)
+	if !uid then return -1,"You are not logged in, so the point could not be saved." 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
+	else
+	  node = Node.new
+	  node.version = 0
+	end
+
+	node.changeset_id = changeset
+	node.lat = lat
+	node.lon = lon
+	node.tags = tags
+	node.visible = visible
+	node.save_with_history!
+
+	[0, id, node.id, node.version]
   end
 
-  def createuniquenodes(way,uqn_name,nodelist) #:doc:
-    # 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)
+  # 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 getpoi(id,version) #:doc:
+	if version>0 then
+	  n = OldNode.find(id, :conditions=>['version=?',version])
+	else
+	  n = Node.find(id)
+	end
+
+	if n
+	  return [n.id, n.lon, n.lat, n.tags, n.version]
+	else
+	  return [nil, nil, nil, {}, nil]
+	end
   end
 
+  # Delete way and all constituent nodes. Also removes from any relations.
+  # Returns 0 (success), unchanged way id.
 
+  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
 
-  # ====================================================================
-  # Relations handling
-  # deleteuniquenoderelations(uqn_name,uid,db_now)
-  # deleteitemrelations(way|node,'way'|'node',uid,db_now)
-
-  def deleteuniquenoderelations(uqn_name,uid,db_now) #:doc:
-    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
-
-    relnodes=ActiveRecord::Base.connection.select_all(sql)
-    relnodes.each do |a|
-      removefromrelation(a['node_id'],'node',a['id'],uid,db_now)
-    end
-  end
+	way_id = way_id.to_i
 
-  def deleteitemrelations(objid,type,uid,db_now) #:doc:
-    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
+	# 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')
 
-  def removefromrelation(objid,type,relation,uid,db_now) #:doc:
-    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)
-
-    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
+	way.delete_with_relations_and_nodes_and_history(changeset_id.to_i)
 
-  def sqlescape(a) #:doc:
-    a.gsub(/[\000-\037]/,"").gsub("'","''").gsub(92.chr) {92.chr+92.chr}
+	[0, way_id]
   end
 
-  def tag2array(a) #:doc:
-    tags={}
-    Tags.split(a) do |k, v|
-      tags[k.gsub(':','|')]=v
-    end
-    tags
+
+  # ====================================================================
+  # Support functions
+
+  # 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
+
+	relations.each do |rel|
+	  rel.members.delete_if { |x| x[0] == type and x[1] == objid }
+	  rel.save_with_history!
+	end
   end
 
-  def array2tag(a) #:doc:
-    tags = []
-    a.each do |k,v|
-      if v=='' then next end
-      if v[0,6]=='(type ' then next end
-      tags << [k.gsub('|',':'), v]
-    end
-    return Tags.join(tags)
+  # Break out node tags into a hash
+  # (should become obsolete as of API 0.6)
+
+  def tagstring_to_hash(a) #:doc:
+	tags={}
+	Tags.split(a) do |k, v|
+	  tags[k]=v
+	end
+	tags
   end
 
+  # Authenticate token
+  # (can also be of form user:pass)
+
   def getuserid(token) #:doc:
-    if (token =~ /^(.+)\+(.+)$/) then
-      user = User.authenticate(:username => $1, :password => $2)
-    else
-      user = User.authenticate(:token => token)
-    end
+	if (token =~ /^(.+)\:(.+)$/) then
+	  user = User.authenticate(:username => $1, :password => $2)
+	else
+	  user = User.authenticate(:token => token)
+	end
 
-    return user ? user.id : nil;
+	return user ? user.id : nil;
   end
 
-  # ====================================================================
-  # Co-ordinate conversion
+  # Compare two floating-point numbers to within 0.0000001
 
-  def lat2coord(a,basey,masterscale) #:doc:
-    -(lat2y(a)-basey)*masterscale
+  def fpcomp(a,b) #:doc:
+	return ((a/0.0000001).round==(b/0.0000001).round)
   end
 
-  def long2coord(a,baselong,masterscale) #:doc:
-    (a-baselong)*masterscale
+  # 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) #:doc:
-    180/Math::PI * Math.log(Math.tan(Math::PI/4+a*(Math::PI/180)/2))
-  end
 
-  def coord2lat(a,masterscale,basey) #:doc:
-    y2lat(a/-masterscale+basey)
+  # ====================================================================
+  # Alternative SQL queries for getway/whichways
+
+  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 coord2long(a,masterscale,baselong) #:doc:
-    a/masterscale+baselong
+	
+  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 y2lat(a)
-    180/Math::PI * (2*Math.atan(Math.exp(a*Math::PI/180))-Math::PI/2)
+	
+  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 sql_get_way_version(wayid)
+    ActiveRecord::Base.connection.select_one("SELECT version FROM current_ways WHERE id=#{wayid.to_i}")
+  end
 end
+
+# Local Variables:
+# indent-tabs-mode: t
+# tab-width: 4
+# End: