app/controllers/amf_controller.rb

   1 class AmfController < ApplicationController
   2   require 'stringio'
   3
   4 # to log:
   5 # RAILS_DEFAULT_LOGGER.error("Args: #{args[0]}, #{args[1]}, #{args[2]}, #{args[3]}")
   6
   7         # doesn't appear to set old versions of ways to invisible
   8         # not sure about segments, either...
   9
  10
  11   # ====================================================================
  12   # Main AMF handler
  13
  14   # ---- talk   process AMF request
  15
  16   def talk
  17         req=StringIO.new(request.raw_post)      # Get POST data as request
  18         req.read(2)                                                     # Skip version indicator and client ID
  19         results={}                                                      # Results of each body
  20
  21         # -------------
  22         # Parse request
  23
  24         headers=getint(req)                                     # Read number of headers
  25         for i in (1..headers)                           # Read each header
  26                 name=getstring(req)                             #  |
  27                 req.getc                                                #  | skip boolean
  28                 value=getvalue(req)                             #  |
  29                 header["name"]=value                    #  |
  30         end
  31
  32         bodies=getint(req)                                      # Read number of bodies
  33         for i in (1..bodies)                            # Read each body
  34                 message=getstring(req)                  #  | get message name
  35                 index=getstring(req)                    #  | get index in response sequence
  36                 bytes=getlong(req)                              #  | get total size in bytes
  37                 args=getvalue(req)                              #  | get response (probably an array)
  38
  39                 case message
  40                         when 'getpresets';      results[index]=putdata(index,getpresets)
  41                         when 'whichways';       results[index]=putdata(index,whichways(args))
  42                         when 'getway';          results[index]=putdata(index,getway(args))
  43                         when 'putway';          results[index]=putdata(index,putway(args))
  44                         when 'deleteway';       results[index]=putdata(index,deleteway(args))
  45                 end
  46         end
  47
  48         # ------------------
  49         # Write out response
  50
  51         response.headers["Content-Type"]="application/x-amf"
  52         a,b=results.length.divmod(256)
  53         ans=0.chr+0.chr+0.chr+0.chr+a.chr+b.chr
  54         results.each do |k,v|
  55                 ans+=v
  56         end
  57         render :text=>ans
  58
  59   end
  60
  61
  62         # ====================================================================
  63         # Remote calls
  64
  65         # ----- getpresets
  66         #               return presets,presetmenus and presetnames arrays
  67
  68         def getpresets
  69                 presets={}
  70                 presetmenus={}; presetmenus['point']=[]; presetmenus['way']=[]
  71                 presetnames={}; presetnames['point']={}; presetnames['way']={}
  72                 presettype=''
  73                 presetcategory=''
  74
  75                 File.open("config/potlatch/presets.txt") do |file|
  76                         file.each_line {|line|
  77                                 t=line.chomp
  78                                 if (t=~/(\w+)\/(\w+)/) then
  79                                         presettype=$1
  80                                         presetcategory=$2
  81                                         presetmenus[presettype].push(presetcategory)
  82                                         presetnames[presettype][presetcategory]=["(no preset)"]
  83                                 elsif (t=~/^(.+):\s?(.+)$/) then
  84                                         pre=$1; kv=$2
  85                                         presetnames[presettype][presetcategory].push(pre)
  86                                         presets[pre]={}
  87                                         kv.split(',').each {|a|
  88                                                 if (a=~/^(.+)=(.*)$/) then presets[pre][$1]=$2 end
  89                                         }
  90                                 end
  91                         }
  92                 end
  93                 [presets,presetmenus,presetnames]
  94         end
  95
  96         # ----- whichways(left,bottom,right,top)
  97         #               return array of ways in current bounding box
  98         #               at present, instead of using correct (=more complex) SQL to find
  99         #               corner-crossing ways, it simply enlarges the bounding box by +/- 0.01
 100
 101         def whichways(args)
 102                 waylist=WaySegment.find_by_sql("SELECT DISTINCT current_way_segments.id AS wayid"+
 103                          "  FROM current_way_segments,current_segments,current_nodes "+
 104                          " WHERE segment_id=current_segments.id "+
 105                          "   AND node_a=current_nodes.id "+
 106                          "   AND (latitude  BETWEEN "+(args[1].to_f-0.01).to_s+" AND "+(args[3].to_f+0.01).to_s+") "+
 107                          "   AND (longitude BETWEEN "+(args[0].to_f-0.01).to_s+" AND "+(args[2].to_f+0.01).to_s+")")
 108                 ways=[]
 109                 waylist.each {|a|
 110                         ways<<a.wayid.to_i
 111                 }
 112                 ways
 113         end
 114
 115         # ----- getway (objectname, way, baselong, basey, masterscale)
 116         #               returns objectname, array of co-ordinates, attributes,
 117         #                               xmin,xmax,ymin,ymax
 118
 119         def getway(args)
 120                 objname,wayid,baselong,basey,masterscale=args
 121                 wayid=wayid.to_i
 122                 points=[]
 123                 lastid=-1
 124                 xmin=999999; xmax=-999999
 125                 ymin=999999; ymax=-999999
 126
 127                 readwayquery(wayid).each {|row|
 128                         xs1=long2coord(row['long1'].to_f,baselong,masterscale); ys1=lat2coord(row['lat1'].to_f,basey,masterscale)
 129                         xs2=long2coord(row['long2'].to_f,baselong,masterscale); ys2=lat2coord(row['lat2'].to_f,basey,masterscale)
 130                         if (row['id1'].to_i!=lastid)
 131                                 points<<[xs1,ys1,row['id1'].to_i,0,tag2array(row['tags1']),0]
 132                         end
 133                         lastid=row['id2'].to_i
 134                         points<<[xs2,ys2,row['id2'].to_i,1,tag2array(row['tags2']),row['segment_id'].to_i]
 135                         xmin=[xmin,row['long1'].to_f,row['long2'].to_f].min
 136                         xmax=[xmax,row['long1'].to_f,row['long2'].to_f].max
 137                         ymin=[ymin,row['lat1'].to_f,row['lat2'].to_f].min
 138                         ymax=[ymax,row['lat1'].to_f,row['lat2'].to_f].max
 139                 }
 140
 141                 attributes={}
 142                 attrlist=ActiveRecord::Base.connection.select_all "SELECT k,v FROM current_way_tags WHERE id=#{wayid}"
 143                 attrlist.each {|a| attributes[a['k']]=a['v'] }
 144
 145                 [objname,points,attributes,xmin,xmax,ymin,ymax]
 146         end
 147
 148         # ----- putway (user token, way, array of co-ordinates, array of attributes,
 149         #                               baselong, basey, masterscale)
 150         #               returns current way ID, new way ID, hash of renumbered nodes,
 151         #                               xmin,xmax,ymin,ymax
 152
 153         def putway(args)
 154                 usertoken,originalway,points,attributes,baselong,basey,masterscale=args
 155                 uid=getuserid(usertoken); if !uid then return end
 156                 db_uqs='uniq'+usertoken+originalway.to_i.abs.to_s+Time.new.to_i.to_s    # temp uniquesegments table name, typically 51 chars
 157                 db_now='@now'+usertoken+originalway.to_i.abs.to_s+Time.new.to_i.to_s    # 'now' variable name, typically 51 chars
 158                 ActiveRecord::Base.connection.execute("SET #{db_now}=NOW()")
 159                 originalway=originalway.to_i
 160
 161                 # -- 3. read original way into memory
 162
 163                 xc={}; yc={}; tagc={}; seg={}
 164                 if (originalway>0)
 165                         way=originalway
 166                         readwayquery(way).each { |row|
 167                                 id1=row['id1'].to_i; xc[id1]=row['long1'].to_f; yc[id1]=row['lat1'].to_f; tagc[id1]=row['tags1']
 168                                 id2=row['id2'].to_i; xc[id2]=row['long2'].to_f; yc[id2]=row['lat2'].to_f; tagc[id2]=row['tags2']
 169                                 seg[row['segment_id'].to_i]=id1.to_s+'-'+id2.to_s
 170                         }
 171                 else
 172                         way=ActiveRecord::Base.connection.insert("INSERT INTO current_ways (user_id,timestamp,visible) VALUES (#{uid},#{db_now},1)")
 173                 end
 174
 175                 # -- 4. get version by inserting new row into ways
 176
 177                 version=ActiveRecord::Base.connection.insert("INSERT INTO ways (id,user_id,timestamp,visible) VALUES (#{way},#{uid},#{db_now},1)")
 178
 179                 # -- 5. compare nodes and update xmin,xmax,ymin,ymax
 180
 181                 xmin=999999; xmax=-999999
 182                 ymin=999999; ymax=-999999
 183                 insertsql=''
 184                 nodelist=''
 185                 renumberednodes={}
 186
 187                 points.each_index do |i|
 188                         xs=coord2long(points[i][0],masterscale,baselong)
 189                         ys=coord2lat(points[i][1],masterscale,basey)
 190                         xmin=[xs,xmin].min; xmax=[xs,xmax].max
 191                         ymin=[ys,ymin].min; ymax=[ys,ymax].max
 192                         node=points[i][2].to_i
 193                         tagstr=array2tag(points[i][4])
 194                         tagsql="'"+sqlescape(tagstr)+"'"
 195
 196                         # compare node
 197                         if node<0
 198                                 # new node - create
 199                                 newnode=ActiveRecord::Base.connection.insert("INSERT INTO current_nodes (   latitude,longitude,timestamp,user_id,visible,tags) VALUES (           #{ys},#{xs},#{db_now},#{uid},1,#{tagsql})")
 200                                                 ActiveRecord::Base.connection.insert("INSERT INTO nodes         (id,latitude,longitude,timestamp,user_id,visible,tags) VALUES (#{newnode},#{ys},#{xs},#{db_now},#{uid},1,#{tagsql})")
 201                                 points[i][2]=newnode
 202                                 renumberednodes[node.to_s]=newnode.to_s
 203
 204                         elsif xc.has_key?(node)
 205                                 # old node from original way - update
 206                                 if (xs!=xc[node] or (ys/0.0000001).round!=(yc[node]/0.0000001).round or tagstr!=tagc[node])
 207                                         ActiveRecord::Base.connection.insert("INSERT INTO nodes (id,latitude,longitude,timestamp,user_id,visible,tags) VALUES (#{node},#{ys},#{xs},#{db_now},#{uid},1,#{tagsql})")
 208                                         ActiveRecord::Base.connection.update("UPDATE current_nodes SET latitude=#{ys},longitude=#{xs},timestamp=#{db_now},user_id=#{uid},tags=#{tagsql},visible=1 WHERE id=#{node}")
 209                                 else
 210                                         if (nodelist!='') then nodelist+=',' end; nodelist+=node.to_s
 211                                 end
 212                         else
 213                                 # old node, created in another way and now added to this way
 214                                 if (nodelist!='') then nodelist+=',' end; nodelist+=node.to_s
 215                         end
 216
 217                 end
 218
 219                 if nodelist!='' then
 220                         ActiveRecord::Base.connection.update("UPDATE current_nodes SET timestamp=#{db_now},user_id=#{uid},visible=1 WHERE id IN (#{nodelist})")
 221                 end
 222
 223                 # -- 6.i compare segments
 224
 225                 numberedsegments={}
 226                 seglist=''
 227                 for i in (0..(points.length-2))
 228                         if (points[i+1][3].to_i==0) then next end
 229                         segid=points[i+1][5].to_i
 230                         from =points[i  ][2].to_i
 231                         to   =points[i+1][2].to_i
 232                         if seg.has_key?(segid)
 233                                 if seg[segid]=="#{from}-#{to}" then
 234                                         if (seglist!='') then seglist+=',' end; seglist+=segid.to_s
 235                                         next
 236                                 end
 237                         end
 238                         segid=ActiveRecord::Base.connection.insert("INSERT INTO current_segments (   node_a,node_b,timestamp,user_id,visible,tags) VALUES (         #{from},#{to},#{db_now},#{uid},1,'')")
 239                                   ActiveRecord::Base.connection.insert("INSERT INTO segments         (id,node_a,node_b,timestamp,user_id,visible,tags) VALUES (#{segid},#{from},#{to},#{db_now},#{uid},1,'')")
 240                         points[i+1][5]=segid
 241                         numberedsegments[(i+1).to_s]=segid.to_s
 242                 end
 243                 # numberedsegments.each{|a,b| RAILS_DEFAULT_LOGGER.error("Sending back: seg no. #{a} -> id #{b}") }
 244
 245                 if seglist!='' then
 246                         ActiveRecord::Base.connection.update("UPDATE current_segments SET timestamp=#{db_now},user_id=#{uid},visible=1 WHERE id IN (#{seglist})")
 247                 end
 248
 249
 250                 # -- 6.ii insert new way segments
 251
 252                 createuniquesegments(way,db_uqs)
 253
 254                 # a=''
 255                 # ActiveRecord::Base.connection.select_values("SELECT segment_id FROM #{db_uqs}").each {|b| a+=b+',' }
 256                 # RAILS_DEFAULT_LOGGER.error("Unique segments are #{a}")
 257                 # a=ActiveRecord::Base.connection.select_value("SELECT #{db_now}")
 258                 # RAILS_DEFAULT_LOGGER.error("Timestamp of this edit is #{a}")
 259                 # RAILS_DEFAULT_LOGGER.error("Userid of this edit is #{uid}")
 260
 261                 #               delete nodes from uniquesegments (and not in modified way)
 262
 263                 sql=<<-EOF
 264                         INSERT INTO nodes (id,latitude,longitude,timestamp,user_id,visible)
 265                         SELECT DISTINCT cn.id,cn.latitude,cn.longitude,#{db_now},#{uid},0
 266                           FROM current_nodes AS cn,
 267                                    current_segments AS cs,
 268                                    #{db_uqs} AS us
 269                          WHERE(cn.id=cs.node_a OR cn.id=cs.node_b)
 270                            AND cs.id=us.segment_id AND cs.visible=1
 271                            AND (cn.timestamp!=#{db_now} OR cn.user_id!=#{uid})
 272                 EOF
 273                 ActiveRecord::Base.connection.insert(sql)
 274
 275                 sql=<<-EOF
 276                         UPDATE current_nodes AS cn,
 277                                    current_segments AS cs,
 278                                    #{db_uqs} AS us
 279                            SET cn.timestamp=#{db_now},cn.visible=0,cn.user_id=#{uid}
 280                          WHERE (cn.id=cs.node_a OR cn.id=cs.node_b)
 281                            AND cs.id=us.segment_id AND cs.visible=1
 282                            AND (cn.timestamp!=#{db_now} OR cn.user_id!=#{uid})
 283                 EOF
 284                 ActiveRecord::Base.connection.update(sql)
 285
 286                 #               delete segments from uniquesegments (and not in modified way)
 287
 288                 sql=<<-EOF
 289                         INSERT INTO segments (id,node_a,node_b,timestamp,user_id,visible)
 290                         SELECT DISTINCT segment_id,node_a,node_b,#{db_now},#{uid},0
 291                           FROM current_segments AS cs, #{db_uqs} AS us
 292                          WHERE cs.id=us.segment_id AND cs.visible=1
 293                            AND (cs.timestamp!=#{db_now} OR cs.user_id!=#{uid})
 294                 EOF
 295                 ActiveRecord::Base.connection.insert(sql)
 296
 297                 sql=<<-EOF
 298                            UPDATE current_segments AS cs, #{db_uqs} AS us
 299                                   SET cs.timestamp=#{db_now},cs.visible=0,cs.user_id=#{uid}
 300                                 WHERE cs.id=us.segment_id AND cs.visible=1
 301                                   AND (cs.timestamp!=#{db_now} OR cs.user_id!=#{uid})
 302                 EOF
 303                 ActiveRecord::Base.connection.update(sql)
 304                 ActiveRecord::Base.connection.execute("DROP TABLE #{db_uqs}")
 305
 306                 #               insert new version of route into way_segments
 307
 308                 insertsql =''
 309                 currentsql=''
 310                 sequence  =1
 311                 for i in (0..(points.length-2))
 312                         if (points[i+1][3].to_i==0) then next end
 313                         if insertsql !='' then insertsql +=',' end
 314                         if currentsql!='' then currentsql+=',' end
 315                         insertsql +="(#{way},#{points[i+1][5]},#{version})"
 316                         currentsql+="(#{way},#{points[i+1][5]},#{sequence})"
 317                         sequence  +=1
 318                 end
 319
 320                 ActiveRecord::Base.connection.execute("DELETE FROM current_way_segments WHERE id=#{way}");
 321                 ActiveRecord::Base.connection.insert("INSERT INTO         way_segments (id,segment_id,version    ) VALUES #{insertsql}");
 322                 ActiveRecord::Base.connection.insert("INSERT INTO current_way_segments (id,segment_id,sequence_id) VALUES #{currentsql}");
 323
 324                 # -- 7. insert new way tags
 325
 326                 insertsql =''
 327                 currentsql=''
 328                 attributes.each do |k,v|
 329                         if v=='' then next end
 330                         if v[0,6]=='(type ' then next end
 331                         if insertsql !='' then insertsql +=',' end
 332                         if currentsql!='' then currentsql+=',' end
 333                         insertsql +="(#{way},'"+sqlescape(k)+"','"+sqlescape(v)+"',version)"
 334                         currentsql+="(#{way},'"+sqlescape(k)+"','"+sqlescape(v)+"')"
 335                 end
 336
 337                 ActiveRecord::Base.connection.execute("DELETE FROM current_way_tags WHERE id=#{way}")
 338                 if (insertsql !='') then ActiveRecord::Base.connection.insert("INSERT INTO way_tags (id,k,v,version) VALUES #{insertsql}" ) end
 339                 if (currentsql!='') then ActiveRecord::Base.connection.insert("INSERT INTO current_way_tags (id,k,v) VALUES #{currentsql}") end
 340
 341                 [originalway,way,renumberednodes,numberedsegments,xmin,xmax,ymin,ymax]
 342         end
 343
 344         # ----- deleteway (user token, way)
 345         #               returns way ID only
 346
 347         def deleteway(args)
 348                 usertoken,way=args
 349                 uid=getuserid(usertoken); if !uid then return end
 350                 way=way.to_i
 351
 352                 db_uqs='uniq'+usertoken+way.to_i.abs.to_s+Time.new.to_i.to_s    # temp uniquesegments table name, typically 51 chars
 353                 db_now='@now'+usertoken+way.to_i.abs.to_s+Time.new.to_i.to_s    # 'now' variable name, typically 51 chars
 354                 ActiveRecord::Base.connection.execute("SET #{db_now}=NOW()")
 355                 createuniquesegments(way,db_uqs)
 356
 357                 sql=<<-EOF
 358                         INSERT INTO nodes (id,latitude,longitude,timestamp,user_id,visible)
 359                         SELECT DISTINCT cn.id,cn.latitude,cn.longitude,#{db_now},#{uid},0
 360                           FROM current_nodes AS cn,
 361                                    current_segments AS cs,
 362                                    #{db_uqs} AS us
 363                          WHERE (cn.id=cs.node_a OR cn.id=cs.node_b)
 364                            AND cs.id=us.segment_id
 365                 EOF
 366                 ActiveRecord::Base.connection.insert(sql)
 367
 368                 sql=<<-EOF
 369                         UPDATE current_nodes AS cn,
 370                                    current_segments AS cs,
 371                                    #{db_uqs} AS us
 372                            SET cn.timestamp=#{db_now},cn.visible=0,cn.user_id=#{uid}
 373                          WHERE (cn.id=cs.node_a OR cn.id=cs.node_b)
 374                            AND cs.id=us.segment_id
 375                 EOF
 376                 ActiveRecord::Base.connection.update(sql)
 377
 378                 # -     delete any otherwise unused segments
 379
 380                 sql=<<-EOF
 381                         INSERT INTO segments (id,node_a,node_b,timestamp,user_id,visible)
 382                         SELECT DISTINCT segment_id,node_a,node_b,#{db_now},#{uid},0
 383                           FROM current_segments AS cs, #{db_uqs} AS us
 384                          WHERE cs.id=us.segment_id
 385                 EOF
 386                 ActiveRecord::Base.connection.insert(sql)
 387
 388                 sql=<<-EOF
 389                         UPDATE current_segments AS cs, #{db_uqs} AS us
 390                            SET cs.timestamp=#{db_now},cs.visible=0,cs.user_id=#{uid}
 391                          WHERE cs.id=us.segment_id
 392                 EOF
 393                 ActiveRecord::Base.connection.update(sql)
 394                 ActiveRecord::Base.connection.execute("DROP TABLE #{db_uqs}")
 395
 396                 # - delete way
 397
 398                 ActiveRecord::Base.connection.insert("INSERT INTO ways (id,user_id,timestamp,visible) VALUES (#{way},#{uid},#{db_now},0)")
 399                 ActiveRecord::Base.connection.update("UPDATE current_ways SET user_id=#{uid},timestamp=#{db_now},visible=0 WHERE id=#{way}")
 400                 ActiveRecord::Base.connection.execute("DELETE FROM current_way_segments WHERE id=#{way}")
 401                 ActiveRecord::Base.connection.execute("DELETE FROM current_way_tags WHERE id=#{way}")
 402
 403                 way
 404         end
 405
 406         # ====================================================================
 407         # Support functions for remote calls
 408
 409         def readwayquery(id)
 410                 ActiveRecord::Base.connection.select_all "SELECT n1.latitude AS lat1,n1.longitude AS long1,n1.id AS id1,n1.tags as tags1, "+
 411                         "                 n2.latitude AS lat2,n2.longitude AS long2,n2.id AS id2,n2.tags as tags2,segment_id "+
 412                         "    FROM current_way_segments,current_segments,current_nodes AS n1,current_nodes AS n2 "+
 413                         "   WHERE current_way_segments.id=#{id} "+
 414                         "     AND segment_id=current_segments.id "+
 415                         "     AND n1.id=node_a and n2.id=node_b "+
 416                         "   ORDER BY sequence_id"
 417         end
 418
 419         def createuniquesegments(way,uqs_name)
 420                 sql=<<-EOF
 421                         CREATE TEMPORARY TABLE #{uqs_name}
 422                                                         SELECT a.segment_id,COUNT(a.segment_id) AS ct
 423                                                           FROM current_way_segments AS a, current_way_segments AS b
 424                                                          WHERE a.segment_id=b.segment_id
 425                                                            AND a.id=#{way}
 426                                                   GROUP BY a.segment_id
 427                                                         HAVING ct=1
 428                 EOF
 429                 ActiveRecord::Base.connection.execute(sql)
 430         end
 431
 432
 433         def sqlescape(a)
 434                 a.gsub("'","''").gsub(92.chr,92.chr+92.chr)
 435         end
 436
 437         def tag2array(a)
 438                 tags={}
 439                 a.gsub(';;;','#%').split(';').each do |b|
 440                         b.gsub!('#%',';;;')
 441                         b.gsub!('===','#%')
 442                         k,v=b.split('=')
 443                         tags[k.gsub('#%','=')]=v.gsub('#%','=')
 444                 end
 445                 tags
 446         end
 447
 448         def array2tag(a)
 449                 str=''
 450                 a.each do |k,v|
 451                         if v=='' then next end
 452                         if v[0,6]=='(type ' then next end
 453                         if str!='' then str+=';' end
 454                         str+=k.gsub(';',';;;').gsub('=','===')+'='+v.gsub(';',';;;').gsub('=','===')
 455                 end
 456                 str
 457         end
 458
 459         def getuserid(token)
 460                 token=sqlescape(token)
 461                 ActiveRecord::Base.connection.select_value("SELECT id FROM users WHERE token='#{token}' AND active=1 AND timeout>NOW()")
 462         end
 463
 464
 465
 466         # ====================================================================
 467         # AMF read subroutines
 468
 469         # ----- getint          return two-byte integer
 470         # ----- getlong         return four-byte long
 471         # ----- getstring       return string with two-byte length
 472         # ----- getdouble       return eight-byte double-precision float
 473         # ----- getobject       return object/hash
 474         # ----- getarray        return numeric array
 475
 476         def getint(s)
 477                 s.getc*256+s.getc
 478         end
 479
 480         def getlong(s)
 481                 ((s.getc*256+s.getc)*256+s.getc)*256+s.getc
 482         end
 483
 484         def getstring(s)
 485                 len=s.getc*256+s.getc
 486                 s.read(len)
 487         end
 488
 489         def getdouble(s)
 490                 a=s.read(8).unpack('G')                 # G big-endian, E little-endian
 491                 a[0]
 492         end
 493
 494         def getarray(s)
 495                 len=getlong(s)
 496                 arr=[]
 497                 for i in (0..len-1)
 498                         arr[i]=getvalue(s)
 499                 end
 500                 arr
 501         end
 502
 503         def getobject(s)
 504                 arr={}
 505                 while (key=getstring(s))
 506                         if (key=='') then break end
 507                         arr[key]=getvalue(s)
 508                 end
 509                 s.getc          # skip the 9 'end of object' value
 510                 arr
 511         end
 512
 513         # ----- getvalue        parse and get value
 514
 515         def getvalue(s)
 516                 case s.getc
 517                         when 0; return getdouble(s)                     # number
 518                         when 1; return s.getc                           # boolean
 519                         when 2; return getstring(s)                     # string
 520                         when 3; return getobject(s)                     # object/hash
 521                         when 5; return nil                                      # null
 522                         when 6; return nil                                      # undefined
 523                         when 8; s.read(4)                                       # mixedArray
 524                                         return getobject(s)                     #  |
 525                         when 10;return getarray(s)                      # array
 526                         else;   return nil                                      # error
 527                 end
 528         end
 529
 530         # ====================================================================
 531         # AMF write subroutines
 532
 533         # ----- putdata         envelope data into AMF writeable form
 534         # ----- encodevalue     pack variables as AMF
 535
 536         def putdata(index,n)
 537                 d =encodestring(index+"/onResult")
 538                 d+=encodestring("null")
 539                 d+=[-1].pack("N")
 540                 d+=encodevalue(n)
 541         end
 542
 543         def encodevalue(n)
 544                 case n.class.to_s
 545                         when 'Array'
 546                                 a=10.chr+encodelong(n.length)
 547                                 n.each do |b|
 548                                         a+=encodevalue(b)
 549                                 end
 550                                 a
 551                         when 'Hash'
 552                                 a=3.chr
 553                                 n.each do |k,v|
 554                                         a+=encodestring(k)+encodevalue(v)
 555                                 end
 556                                 a+0.chr+0.chr+9.chr
 557                         when 'String'
 558                                 2.chr+encodestring(n)
 559                         when 'Bignum','Fixnum','Float'
 560                                 0.chr+encodedouble(n)
 561                         when 'NilClass'
 562                                 5.chr
 563                         else
 564                                 RAILS_DEFAULT_LOGGER.error("Unexpected Ruby type for AMF conversion: "+n.class.to_s)
 565                 end
 566         end
 567
 568         # ----- encodestring    encode string with two-byte length
 569         # ----- encodedouble    encode number as eight-byte double precision float
 570         # ----- encodelong              encode number as four-byte long
 571
 572         def encodestring(n)
 573                 a,b=n.size.divmod(256)
 574                 a.chr+b.chr+n
 575         end
 576
 577         def encodedouble(n)
 578                 [n].pack('G')
 579         end
 580
 581         def encodelong(n)
 582                 [n].pack('N')
 583         end
 584
 585         # ====================================================================
 586         # Co-ordinate conversion
 587
 588         def lat2coord(a,basey,masterscale)
 589                 -(lat2y(a)-basey)*masterscale+250
 590         end
 591
 592         def long2coord(a,baselong,masterscale)
 593                 (a-baselong)*masterscale+350
 594         end
 595
 596         def lat2y(a)
 597                 180/Math::PI * Math.log(Math.tan(Math::PI/4+a*(Math::PI/180)/2))
 598         end
 599
 600         def coord2lat(a,masterscale,basey)
 601                 y2lat((a-250)/-masterscale+basey)
 602         end
 603
 604         def coord2long(a,masterscale,baselong)
 605                 (a-350)/masterscale+baselong
 606         end
 607
 608         def y2lat(a)
 609                 180/Math::PI * (2*Math.atan(Math.exp(a*Math::PI/180))-Math::PI/2)
 610         end
 611
 612
 613 end