app/controllers/amf_controller.rb

   1 class AmfController < ApplicationController
   2   require 'stringio'
   3
   4   # Still to do:
   5   # - all db interaction
   6   # - user authentication
   7   # - (also pass lat/lon through from view tab to edit tab)
   8
   9 # to log:
  10 # RAILS_DEFAULT_LOGGER.error("Args: #{args[0]}, #{args[1]}, #{args[2]}, #{args[3]}")
  11
  12
  13   # ====================================================================
  14   # Main AMF handler
  15
  16   # ---- talk   process AMF request
  17
  18   def talk
  19         req=StringIO.new(request.raw_post)      # Get POST data as request
  20         req.read(2)                                                     # Skip version indicator and client ID
  21         results={}                                                      # Results of each body
  22
  23         # -------------
  24         # Parse request
  25
  26         headers=getint(req)                                     # Read number of headers
  27         for i in (1..headers)                           # Read each header
  28                 name=getstring(req)                             #  |
  29                 req.getc                                                #  | skip boolean
  30                 value=getvalue(req)                             #  |
  31                 header["name"]=value                    #  |
  32         end
  33
  34         bodies=getint(req)                                      # Read number of bodies
  35         for i in (1..bodies)                            # Read each body
  36                 message=getstring(req)                  #  | get message name
  37                 index=getstring(req)                    #  | get index in response sequence
  38                 bytes=getlong(req)                              #  | get total size in bytes
  39                 args=getvalue(req)                              #  | get response (probably an array)
  40
  41                 case message
  42                         when 'getpresets';      results[index]=putdata(index,getpresets)
  43                         when 'whichways';       results[index]=putdata(index,whichways(args))
  44                         when 'getway';          results[index]=putdata(index,getway(args))
  45                         when 'putway';          results[index]=putdata(index,putway(args))
  46                         when 'deleteway';       results[index]=putdata(index,deleteway(args))
  47                 end
  48         end
  49
  50         # ------------------
  51         # Write out response
  52
  53         response.headers["Content-Type"]="application/x-amf"
  54         a,b=results.length.divmod(256)
  55         ans=0.chr+0.chr+0.chr+0.chr+a.chr+b.chr
  56         results.each do |k,v|
  57                 ans+=v
  58         end
  59         render :text=>ans
  60
  61   end
  62
  63
  64         # ====================================================================
  65         # Remote calls
  66
  67         def getpresets
  68                 presets={}
  69                 presetmenus={}; presetmenus['point']=[]; presetmenus['way']=[]
  70                 presetnames={}; presetnames['point']={}; presetnames['way']={}
  71                 presettype=''
  72                 presetcategory=''
  73
  74                 File.open("config/potlatch/presets.txt") do |file|
  75                         file.each_line {|line|
  76                                 t=line.chomp
  77                                 if (t=~/(\w+)\/(\w+)/) then
  78                                         presettype=$1
  79                                         presetcategory=$2
  80                                         presetmenus[presettype].push(presetcategory)
  81                                         presetnames[presettype][presetcategory]=["(no preset)"]
  82                                 elsif (t=~/^(.+):\s?(.+)$/) then
  83                                         pre=$1; kv=$2
  84                                         presetnames[presettype][presetcategory].push(pre)
  85                                         presets[pre]={}
  86                                         kv.split(',').each {|a|
  87                                                 if (a=~/^(.+)=(.*)$/) then presets[pre][$1]=$2 end
  88                                         }
  89                                 end
  90                         }
  91                 end
  92                 [presets,presetmenus,presetnames]
  93         end
  94
  95         def whichways(args)
  96                 waylist=WaySegment.find_by_sql("SELECT DISTINCT current_way_segments.id AS wayid"+
  97                          "  FROM current_way_segments,current_segments,current_nodes "+
  98                          " WHERE segment_id=current_segments.id "+
  99                          "   AND node_a=current_nodes.id "+
 100                          "   AND (latitude  BETWEEN "+(args[1].to_f-0.01).to_s+" AND "+(args[3].to_f+0.01).to_s+") "+
 101                          "   AND (longitude BETWEEN "+(args[0].to_f-0.01).to_s+" AND "+(args[2].to_f+0.01).to_s+")")
 102                 ways=[]
 103                 waylist.each {|a|
 104                         ways<<a.wayid.to_i
 105 RAILS_DEFAULT_LOGGER.error("Found #{a.wayid.to_i}")
 106                 }
 107                 ways
 108         end
 109
 110         def getway(args)
 111                 objname,wayid,$baselong,$basey,$masterscale=args
 112                 wayid=wayid.to_i
 113                 points=[]
 114                 lastid=-1
 115                 xmin=999999; xmax=-999999
 116                 ymin=999999; ymax=-999999
 117
 118 RAILS_DEFAULT_LOGGER.error("Looking for way #{wayid}")
 119                 nodelist=ActiveRecord::Base.connection.select_all "SELECT n1.latitude AS lat1,n1.longitude AS long1,n1.id AS id1,n1.tags as tags1, "+
 120                         "                 n2.latitude AS lat2,n2.longitude AS long2,n2.id AS id2,n2.tags as tags2,segment_id "+
 121                         "    FROM current_way_segments,current_segments,current_nodes AS n1,current_nodes AS n2 "+
 122                         "   WHERE current_way_segments.id=#{wayid} "+
 123                         "     AND segment_id=current_segments.id "+
 124                         "     AND n1.id=node_a and n2.id=node_b "+
 125                         "   ORDER BY sequence_id"
 126                 nodelist.each {|row|
 127                         xs1=long2coord(row['long1'].to_f); ys1=lat2coord(row['lat1'].to_f)
 128                         xs2=long2coord(row['long2'].to_f); ys2=lat2coord(row['lat2'].to_f)
 129                         if (row['id1'].to_i!=lastid)
 130                                 points<<[xs1,ys1,row['id1'].to_i,0,tag2array(row['tags1']),0]
 131                         end
 132                         lastid=row['id2'].to_i
 133                         points<<[xs2,ys2,row['id2'].to_i,1,tag2array(row['tags2']),row['segment_id'].to_i]
 134                         xmin=[xmin,row['long1'].to_f,row['long2'].to_f].min
 135                         xmax=[xmax,row['long1'].to_f,row['long2'].to_f].max
 136                         ymin=[ymin,row['lat1'].to_f,row['lat2'].to_f].min
 137                         ymax=[ymax,row['lat1'].to_f,row['lat2'].to_f].max
 138                 }
 139
 140                 attributes={}
 141                 attrlist=ActiveRecord::Base.connection.select_all "SELECT k,v FROM current_way_tags WHERE id=#{wayid}"
 142                 attrlist.each {|a| attributes[a['k']]=a['v'] }
 143
 144 RAILS_DEFAULT_LOGGER.error("Way #{wayid} #{xmin},#{xmax},#{ymin},#{ymax}")
 145                 [objname,points,attributes,xmin,xmax,ymin,ymax]
 146         end
 147
 148         def putway(args)
 149                 # to do
 150         end
 151
 152         def deleteway(args)
 153                 # to do
 154         end
 155
 156         # need support functions here too:
 157         #       database support functions (readwayquery, createuniquesegments)
 158         #       tag2array, array2tag
 159         #       getuserid
 160
 161         def tag2array(a)
 162                 tags={}
 163                 a.gsub('\;','#%').split(';').each do |b|
 164                         b.gsub!('#%',';')
 165                         k,v=b.split('=')
 166                         tags[k]=v
 167                 end
 168                 tags
 169         end
 170
 171
 172         # ====================================================================
 173         # AMF read subroutines
 174
 175         # ----- getint          return two-byte integer
 176         # ----- getlong         return four-byte long
 177         # ----- getstring       return string with two-byte length
 178         # ----- getdouble       return eight-byte double-precision float
 179         # ----- getobject       return object/hash
 180         # ----- getarray        return numeric array
 181
 182         def getint(s)
 183                 s.getc*256+s.getc
 184         end
 185
 186         def getlong(s)
 187                 ((s.getc*256+s.getc)*256+s.getc)*256+s.getc
 188         end
 189
 190         def getstring(s)
 191                 len=s.getc*256+s.getc
 192                 s.read(len)
 193         end
 194
 195         def getdouble(s)
 196                 a=s.read(8).unpack('G')                 # G big-endian, E little-endian
 197                 a[0]
 198         end
 199
 200         def getarray(s)
 201                 len=getlong(s)
 202                 arr=[]
 203                 for i in (0..len-1)
 204                         arr[i]=getvalue(s)
 205                 end
 206                 arr
 207         end
 208
 209         def getobject(s)
 210                 arr={}
 211                 while (key=getstring(s))
 212                         if (key=='') then break end
 213                         arr[key]=getvalue(s)
 214                 end
 215                 s.getc          # skip the 9 'end of object' value
 216                 arr
 217         end
 218
 219         # ----- getvalue        parse and get value
 220
 221         def getvalue(s)
 222                 case s.getc
 223                         when 0; return getdouble(s)                     # number
 224                         when 1; return s.getc                           # boolean
 225                         when 2; return getstring(s)                     # string
 226                         when 3; return getobject(s)                     # object/hash
 227                         when 5; return nil                                      # null
 228                         when 6; return nil                                      # undefined
 229                         when 8; s.read(4)                                       # mixedArray
 230                                         return getobject(s)                     #  |
 231                         when 10;return getarray(s)                      # array
 232                         else;   return nil                                      # error
 233                 end
 234         end
 235
 236         # ====================================================================
 237         # AMF write subroutines
 238
 239         # ----- putdata         envelope data into AMF writeable form
 240         # ----- encodevalue     pack variables as AMF
 241
 242         def putdata(index,n)
 243                 d =encodestring(index+"/onResult")
 244                 d+=encodestring("null")
 245                 d+=[-1].pack("N")
 246                 d+=encodevalue(n)
 247         end
 248
 249         def encodevalue(n)
 250                 case n.class.to_s
 251                         when 'Array'
 252                                 a=10.chr+encodelong(n.length)
 253                                 n.each do |b|
 254                                         a+=encodevalue(b)
 255                                 end
 256                                 a
 257                         when 'Hash'
 258                                 a=3.chr
 259                                 n.each do |k,v|
 260                                         a+=encodestring(k)+encodevalue(v)
 261                                 end
 262                                 a+0.chr+0.chr+9.chr
 263                         when 'String'
 264                                 2.chr+encodestring(n)
 265                         when 'Bignum','Fixnum','Float'
 266                                 0.chr+encodedouble(n)
 267                         when 'NilClass'
 268                                 5.chr
 269                         else
 270                                 RAILS_DEFAULT_LOGGER.error("Unexpected Ruby type for AMF conversion: "+n.class.to_s)
 271                 end
 272         end
 273
 274         # ----- encodestring    encode string with two-byte length
 275         # ----- encodedouble    encode number as eight-byte double precision float
 276         # ----- encodelong              encode number as four-byte long
 277
 278         def encodestring(n)
 279                 a,b=n.size.divmod(256)
 280                 a.chr+b.chr+n
 281         end
 282
 283         def encodedouble(n)
 284                 [n].pack('G')
 285         end
 286
 287         def encodelong(n)
 288                 [n].pack('N')
 289         end
 290
 291         # ====================================================================
 292         # Co-ordinate conversion
 293
 294         def lat2coord(a)
 295                 -(lat2y(a)-$basey)*$masterscale+250
 296         end
 297
 298         def long2coord(a)
 299                 (a-$baselong)*$masterscale+350
 300         end
 301
 302         def lat2y(a)
 303                 180/Math::PI * Math.log(Math.tan(Math::PI/4+a*(Math::PI/180)/2))
 304         end
 305
 306         def coord2lat(a)
 307                 y2lat((a-250)/-$masterscale+$basey)
 308         end
 309
 310         def coord2long(a)
 311                 (a-350)/$masterscale+$baselong
 312         end
 313
 314         def y2lat(a)
 315                 180/Math::PI * (2*Math.atan(Math.exp(a*Math::PI/180))-Math::PI/2)
 316         end
 317
 318
 319 end