var RegionList = (function(){

  var RegionList = {}
  var regions = RegionList.regions

  RegionList.build = function(){
    var segments = RegionList.getSortedSegments()

//     var xx = t % (segments[0].x.a - segments[segments.length-1].x.b)

    // loop over them from left to right
//   console.log(segments.map(function(s){ return s.toString() }).join("\n"))

    var rooms = []
    var open_segments = []
    
    var segment, open_segment, x_segment, y_segments, overlapped

    for (var i = 0; i < segments.length; i++) {
      segment = segments[i]
      if (! segment.isVertical()) {
        continue
      }
      overlapped = false
      for (var j = 0; j < open_segments.length; j++) {
        open_segment = open_segments[j]
        if (segment.y.overlaps(open_segment.y)) {
          // if we have overlap, it means we have made a full room
          console.log(segment.y+"", "overlaps", open_segment.y+"")
          overlapped = true
          open_segments.splice(j--, 1)

          x_segment = new vec2( open_segment.x.a, segment.x.b )
          y_segments = segment.y.split(open_segment.y, TOP, BOTTOM)
          console.log(y_segments.map(function(s){ return s+"" }).join("\n"))
          y_segments.forEach(function(seg){

            rooms.push(new Rect( x_segment, seg[0] ))

            var new_seg = new Rect( segment.x, seg[0] )
            open_segments.shift(new_seg)
            j++
          })
        }
      }
      if (! overlapped) {
        open_segments.push(segment)
      }
    }
    
//   console.log(rooms.map(function(s){ return s.toString() }).join("\n"))
    
    return { rooms: rooms, open_segments: open_segments, segments: segments }
  }
  
  RegionList.getSortedSegments = function(){
    // get a list of all segments from these polylines
    var segments = shapes.getAllSegments()

    // re-orient them so they're either facing up or right and make them into rects
    segments = segments.map(function(segment){
      // vertical
      if (segment[0].a == segment[1].a) {
        if (segment[0].b > segment[1].b) {
          segment.push(segment.shift())
        }
      }
      // horizontal
      else if (segment[0].b == segment[1].b) {
        if (segment[0].a > segment[1].a) {
          segment.push(segment.shift())
        }
      }
      return new Rect( segment[0].a, segment[0].b, segment[1].a, segment[1].b )
    })
    
    return sort.rects_by_position(segments)
  }

  return RegionList
  
})()