lysenko-interval-tree.js

/*
 This code pulled from
 https://github.com/mikolalysenko/binary-search-bounds
 https://github.com/mikolalysenko/interval-tree-1d

 and concatenated to eliminate modules

The MIT License (MIT)

Copyright (c) 2013-2015 Mikola Lysenko

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
THE SOFTWARE.

 */

// search-bounds.js

"use strict"

function compileSearch(funcName, predicate, reversed, extraArgs, earlyOut) {
  var code = [
    "function ", funcName, "(a,l,h,", extraArgs.join(","),  "){",
earlyOut ? "" : "var i=", (reversed ? "l-1" : "h+1"),
";while(l<=h){\
var m=(l+h)>>>1,x=a[m]"]
  if(earlyOut) {
    if(predicate.indexOf("c") < 0) {
      code.push(";if(x===y){return m}else if(x<=y){")
    } else {
      code.push(";var p=c(x,y);if(p===0){return m}else if(p<=0){")
    }
  } else {
    code.push(";if(", predicate, "){i=m;")
  }
  if(reversed) {
    code.push("l=m+1}else{h=m-1}")
  } else {
    code.push("h=m-1}else{l=m+1}")
  }
  code.push("}")
  if(earlyOut) {
    code.push("return -1};")
  } else {
    code.push("return i};")
  }
  return code.join("")
}

function compileBoundsSearch(predicate, reversed, suffix, earlyOut) {
  var result = new Function([
  compileSearch("A", "x" + predicate + "y", reversed, ["y"], earlyOut),
  compileSearch("P", "c(x,y)" + predicate + "0", reversed, ["y", "c"], earlyOut),
"function dispatchBsearch", suffix, "(a,y,c,l,h){\
if(typeof(c)==='function'){\
return P(a,(l===void 0)?0:l|0,(h===void 0)?a.length-1:h|0,y,c)\
}else{\
return A(a,(c===void 0)?0:c|0,(l===void 0)?a.length-1:l|0,y)\
}}\
return dispatchBsearch", suffix].join(""))
  return result()
}

var bounds = {
  ge: compileBoundsSearch(">=", false, "GE"),
  gt: compileBoundsSearch(">", false, "GT"),
  lt: compileBoundsSearch("<", true, "LT"),
  le: compileBoundsSearch("<=", true, "LE"),
  eq: compileBoundsSearch("-", true, "EQ", true)
}

// interval-tree.js

var NOT_FOUND = 0
var SUCCESS = 1
var EMPTY = 2

function IntervalTreeNode(mid, left, right, leftPoints, rightPoints) {
  this.mid = mid
  this.left = left
  this.right = right
  this.leftPoints = leftPoints
  this.rightPoints = rightPoints
  this.count = (left ? left.count : 0) + (right ? right.count : 0) + leftPoints.length
}

var proto = IntervalTreeNode.prototype

function copy(a, b) {
  a.mid = b.mid
  a.left = b.left
  a.right = b.right
  a.leftPoints = b.leftPoints
  a.rightPoints = b.rightPoints
  a.count = b.count
}

function rebuild(node, intervals) {
  var ntree = createIntervalTree(intervals)
  node.mid = ntree.mid
  node.left = ntree.left
  node.right = ntree.right
  node.leftPoints = ntree.leftPoints
  node.rightPoints = ntree.rightPoints
  node.count = ntree.count
}

function rebuildWithInterval(node, interval) {
  var intervals = node.intervals([])
  intervals.push(interval)
  rebuild(node, intervals)    
}

function rebuildWithoutInterval(node, interval) {
  var intervals = node.intervals([])
  var idx = intervals.indexOf(interval)
  if(idx < 0) {
    return NOT_FOUND
  }
  intervals.splice(idx, 1)
  rebuild(node, intervals)
  return SUCCESS
}

proto.intervals = function(result) {
  result.push.apply(result, this.leftPoints)
  if(this.left) {
    this.left.intervals(result)
  }
  if(this.right) {
    this.right.intervals(result)
  }
  return result
}

proto.insert = function(interval) {
  var weight = this.count - this.leftPoints.length
  this.count += 1
  if(interval[1] < this.mid) {
    if(this.left) {
      if(4*(this.left.count+1) > 3*(weight+1)) {
        rebuildWithInterval(this, interval)
      } else {
        this.left.insert(interval)
      }
    } else {
      this.left = createIntervalTree([interval])
    }
  } else if(interval[0] > this.mid) {
    if(this.right) {
      if(4*(this.right.count+1) > 3*(weight+1)) {
        rebuildWithInterval(this, interval)
      } else {
        this.right.insert(interval)
      }
    } else {
      this.right = createIntervalTree([interval])
    }
  } else {
    var l = bounds.ge(this.leftPoints, interval, compareBegin)
    var r = bounds.ge(this.rightPoints, interval, compareEnd)
    this.leftPoints.splice(l, 0, interval)
    this.rightPoints.splice(r, 0, interval)
  }
}

proto.remove = function(interval) {
  var weight = this.count - this.leftPoints
  if(interval[1] < this.mid) {
    if(!this.left) {
      return NOT_FOUND
    }
    var rw = this.right ? this.right.count : 0
    if(4 * rw > 3 * (weight-1)) {
      return rebuildWithoutInterval(this, interval)
    }
    var r = this.left.remove(interval)
    if(r === EMPTY) {
      this.left = null
      this.count -= 1
      return SUCCESS
    } else if(r === SUCCESS) {
      this.count -= 1
    }
    return r
  } else if(interval[0] > this.mid) {
    if(!this.right) {
      return NOT_FOUND
    }
    var lw = this.left ? this.left.count : 0
    if(4 * lw > 3 * (weight-1)) {
      return rebuildWithoutInterval(this, interval)
    }
    var r = this.right.remove(interval)
    if(r === EMPTY) {
      this.right = null
      this.count -= 1
      return SUCCESS
    } else if(r === SUCCESS) {
      this.count -= 1
    }
    return r
  } else {
    if(this.count === 1) {
      if(this.leftPoints[0] === interval) {
        return EMPTY
      } else {
        return NOT_FOUND
      }
    }
    if(this.leftPoints.length === 1 && this.leftPoints[0] === interval) {
      if(this.left && this.right) {
        var p = this
        var n = this.left
        while(n.right) {
          p = n
          n = n.right
        }
        if(p === this) {
          n.right = this.right
        } else {
          var l = this.left
          var r = this.right
          p.count -= n.count
          p.right = n.left
          n.left = l
          n.right = r
        }
        copy(this, n)
        this.count = (this.left?this.left.count:0) + (this.right?this.right.count:0) + this.leftPoints.length
      } else if(this.left) {
        copy(this, this.left)
      } else {
        copy(this, this.right)
      }
      return SUCCESS
    }
    for(var l = bounds.ge(this.leftPoints, interval, compareBegin); l<this.leftPoints.length; ++l) {
      if(this.leftPoints[l][0] !== interval[0]) {
        break
      }
      if(this.leftPoints[l] === interval) {
        this.count -= 1
        this.leftPoints.splice(l, 1)
        for(var r = bounds.ge(this.rightPoints, interval, compareEnd); r<this.rightPoints.length; ++r) {
          if(this.rightPoints[r][1] !== interval[1]) {
            break
          } else if(this.rightPoints[r] === interval) {
            this.rightPoints.splice(r, 1)
            return SUCCESS
          }
        }
      }
    }
    return NOT_FOUND
  }
}

function reportLeftRange(arr, hi, cb) {
  for(var i=0; i<arr.length && arr[i][0] <= hi; ++i) {
    var r = cb(arr[i])
    if(r) { return r }
  }
}

function reportRightRange(arr, lo, cb) {
  for(var i=arr.length-1; i>=0 && arr[i][1] >= lo; --i) {
    var r = cb(arr[i])
    if(r) { return r }
  }
}

function reportRange(arr, cb) {
  for(var i=0; i<arr.length; ++i) {
    var r = cb(arr[i])
    if(r) { return r }
  }
}

proto.queryPoint = function(x, cb) {
  if(x < this.mid) {
    if(this.left) {
      var r = this.left.queryPoint(x, cb)
      if(r) { return r }
    }
    return reportLeftRange(this.leftPoints, x, cb)
  } else if(x > this.mid) {
    if(this.right) {
      var r = this.right.queryPoint(x, cb)
      if(r) { return r }
    }
    return reportRightRange(this.rightPoints, x, cb)
  } else {
    return reportRange(this.leftPoints, cb)
  }
}

proto.queryInterval = function(lo, hi, cb) {
  if(lo < this.mid && this.left) {
    var r = this.left.queryInterval(lo, hi, cb)
    if(r) { return r }
  }
  if(hi > this.mid && this.right) {
    var r = this.right.queryInterval(lo, hi, cb)
    if(r) { return r }
  }
  if(hi < this.mid) {
    return reportLeftRange(this.leftPoints, hi, cb)
  } else if(lo > this.mid) {
    return reportRightRange(this.rightPoints, lo, cb)
  } else {
    return reportRange(this.leftPoints, cb)
  }
}

function compareNumbers(a, b) {
  return a - b
}

function compareBegin(a, b) {
  var d = a[0] - b[0]
  if(d) { return d }
  return a[1] - b[1]
}

function compareEnd(a, b) {
  var d = a[1] - b[1]
  if(d) { return d }
  return a[0] - b[0]
}

function createIntervalTree(intervals) {
  if(intervals.length === 0) {
    return null
  }
  var pts = []
  for(var i=0; i<intervals.length; ++i) {
    pts.push(intervals[i][0], intervals[i][1])
  }
  pts.sort(compareNumbers)

  var mid = pts[pts.length>>1]

  var leftIntervals = []
  var rightIntervals = []
  var centerIntervals = []
  for(var i=0; i<intervals.length; ++i) {
    var s = intervals[i]
    if(s[1] < mid) {
      leftIntervals.push(s)
    } else if(mid < s[0]) {
      rightIntervals.push(s)
    } else {
      centerIntervals.push(s)
    }
  }

  //Split center intervals
  var leftPoints = centerIntervals
  var rightPoints = centerIntervals.slice()
  leftPoints.sort(compareBegin)
  rightPoints.sort(compareEnd)

  return new IntervalTreeNode(mid, 
    createIntervalTree(leftIntervals),
    createIntervalTree(rightIntervals),
    leftPoints,
    rightPoints)
}

//User friendly wrapper that makes it possible to support empty trees
function IntervalTree(root) {
  this.root = root
}

var tproto = IntervalTree.prototype

tproto.insert = function(interval) {
  if(this.root) {
    this.root.insert(interval)
  } else {
    this.root = new IntervalTreeNode(interval[0], null, null, [interval], [interval])
  }
}

tproto.remove = function(interval) {
  if(this.root) {
    var r = this.root.remove(interval)
    if(r === EMPTY) {
      this.root = null
    }
    return r !== NOT_FOUND
  }
  return false
}

tproto.queryPoint = function(p, cb) {
  if(this.root) {
    return this.root.queryPoint(p, cb)
  }
}

tproto.queryInterval = function(lo, hi, cb) {
  if(lo <= hi && this.root) {
    return this.root.queryInterval(lo, hi, cb)
  }
}

Object.defineProperty(tproto, "count", {
  get: function() {
    if(this.root) {
      return this.root.count
    }
    return 0
  }
})

Object.defineProperty(tproto, "intervals", {
  get: function() {
    if(this.root) {
      return this.root.intervals([])
    }
    return []
  }
})

function lysenkoIntervalTree(intervals) {
  if(!intervals || intervals.length === 0) {
    return new IntervalTree(null)
  }
  return new IntervalTree(createIntervalTree(intervals))
}