//
// path to HPGL
//
// Neil Gershenfeld 
// (c) Massachusetts Institute of Technology 2021
// 
// This work may be reproduced, modified, distributed, performed, and 
// displayed for any purpose, but must acknowledge the mods
// project. Copyright is retained and must be preserved. The work is 
// provided as is; no warranty is provided, and users accept all 
// liability.
//
// closure
//


(function(){
//
// module globals
//
var mod = {}
//
// name
//
var name = 'path to HPGL (unfinished)'
//
// initialization
//
var init = function() {
   }
//
// inputs
//
var inputs = {
   toolpath:{type:'object',
      event:function(evt){
         mod.name = evt.detail.name
         mod.path = evt.detail.path
         mod.dpi = evt.detail.dpi
         mod.width = evt.detail.width
         mod.height = evt.detail.height
         make_path()
         }}}
//
// outputs
//
var outputs = {
   file:{type:'object',
      event:function(str){
         obj = {}
         obj.name = mod.name+".hpgl"
         obj.contents = str
         mods.output(mod,'file',obj)
         }}}
//
// interface
//
var interface = function(div){
   mod.div = div
   //
   // display file name
   //
   div.appendChild(document.createTextNode(mod.name + '.hpgl'))
   div.appendChild(document.createElement('br'))
   }
//
// local functions
//
function make_path() {
   var units = 25.4/0.025
   var dx = units*mod.width/mod.dpi
   var nx = mod.width
   var scale = dx/(nx-1)
   str = "IN;SP1;" 
   //
   // follow segments
   //
    for (var seg = 0; seg < mod.path.length; ++seg) {
        //
        // Pen up
        //
        x = Math.round(scale * mod.path[seg][0][0])
        y = Math.round(scale * mod.path[seg][0][1])
        str += "PU" + x + "," + y + ";PD"
        //
        // Pen down
        //
        for (var pt = 1; pt < mod.path[seg].length; ++pt) {
            //
            // move to next point
            //
            x = Math.round(scale * mod.path[seg][pt][0])
            y = Math.round(scale * mod.path[seg][pt][1])
            str += x + "," + y
            pt < (mod.path[seg].length - 1) ? str += "," : str += ";"
        }
    }
   //Move to origin
   str += "PU0,0;SP0;IN;"
   //
   // output file
   //
   outputs.file.event(str)
   }
//
// return values
//
return ({
   mod:mod,
   name:name,
   init:init,
   inputs:inputs,
   outputs:outputs,
   interface:interface
   })
}())