// library for creating CuVoodoo Land Pattern (cvlp) JSON files and render them

// create a set of elements with an line element
function cvlp_line(x1, y1, x2, y2, thickness, round=true) {
	var line = {}
    line.type = "line"
	line.x1 = x1
	line.y1 = y1
	line.x2 = x2
	line.y2 = y2
	line.thickness = thickness
	line.round = round
	return [line]
}

// create a set of elements with an arc element
// arc goes angle degrees clockwise from start
function cvlp_arc(x, y, radius, start, angle, thickness, round=true) {
	var arc = {}
	arc.type = "arc"
	arc.x = x
	arc.y = y
	arc.radius = radius
	arc.start = start
	arc.angle = angle
	arc.thickness = thickness
	arc.round = round
	return [arc]
}

// create a set of elements with an pad element
function cvlp_pad(number, x1, y1, x2, y2, thickness, clearance, soldermask, round=true) {
	var pad = {}
    pad.type = "pad"
	pad.number = number
	pad.x1 = x1
	pad.y1 = y1
	pad.x2 = x2
	pad.y2 = y2
	pad.thickness = thickness
	pad.clearance = clearance
	pad.soldermask = soldermask
	pad.round = round
	return [pad]
}

// create a set of elements with an pin element
function cvlp_pin(number, x, y, thickness, drill, clearance, soldermask, round=true) {
	var pin = {}
	pin.type = "pin"
	pin.number = number
	pin.x = x
	pin.y = y
	pin.thickness = thickness
	pin.drill = drill
	pin.clearance = clearance
	pin.soldermask = soldermask
	pin.round = round
	return [pin]
}

// create a set of elements representing a chain of lines
// provide a list of [x,y] coordinates
function cvlp_polyline(points, thickness, closed=false) {
	var polyline = []
	for (var i=0; i<points.length-1; i++) {
		polyline = polyline.concat(cvlp_line(points[i][0], points[i][1], points[i+1][0], points[i+1][1], thickness))
	}
	if (closed) {
		if (points[0][0]!=points[points.length-1][0] && points[0][1]!=points[points.length-1][1]) {
			polyline = polyline.concat(cvlp_line(points[points.length-1][0], points[points.length-1][1], points[0][0], points[0][1], thickness))
		}
	}
	return polyline
}

// create a set of elements representing a rectangle
// provide top corner, size, an radius of corner
function cvlp_rectangle(x, y, width, height, thickness, radius=0, round=true) {
	var rectangle = []
	rectangle = rectangle.concat(cvlp_line(x+radius, y, x+width-radius, y, thickness, round))
	rectangle = rectangle.concat(cvlp_line(x+width, y+radius, x+width, y+height-radius, thickness, round))
	rectangle = rectangle.concat(cvlp_line(x+width-radius, y+height, x+radius, y+height, thickness, round))
	rectangle = rectangle.concat(cvlp_line(x, y+height-radius, x, y+radius, thickness, round))
	if (radius!=0) {
		rectangle = rectangle.concat(cvlp_arc(x+radius, y+radius, radius, 180, 90, thickness, round))
		rectangle = rectangle.concat(cvlp_arc(x+width-radius, y+radius, radius, 270, 90, thickness, round))
		rectangle = rectangle.concat(cvlp_arc(x+width-radius, y+width-radius, radius, 0, 90, thickness, round))
		rectangle = rectangle.concat(cvlp_arc(x+radius, y+width-radius, radius, 90, 90, thickness, round))
	}
	return rectangle
}

// convert value from one unit to another
// units allowed: mm, in, mil
// returns converted value, on null if unknown unit
function convert_unit(value, from, to) {
// don't convert if the unit is the same (avoid calculation imprecisions)
	if (from==to) {
		return value;
	}
	// convert to µm
	var mum = 0;
	switch (from) {
		case 'mm':
			mum = value*1000;
			break;
		case 'in':
			mum = value*1000*25.40;
			break;
		case 'mil':
			mum = value*25.40;
			break;
		default:
			return null;
	}
	switch (to) {
		case 'mm':
			mum = mum/1000;
			break;
		case 'in':
			mum = mum/1000/25.40;
			break;
		case 'mil':
			mum = mum/25.40;
			break;
		default:
			return null;
	}
	return mum;
}

// convert JSON to SVG
function json2svg(json) {
	// create svg
	var svgNS = "http://www.w3.org/2000/svg"
	svg = document.createElementNS(svgNS,'svg')
	svg.setAttribute('xmlns',svgNS)
	svg.setAttribute('version',1.1)
	svg.setAttribute('xmlns:inkscape','http://www.inkscape.org/namespaces/inkscape')
	// set unit
	if (json.unit=="mil") { // mil units are not supported in SVG, convert to inch
		svg.setAttribute('height',(json.height/1000)+'in')
		svg.setAttribute('width',(json.width/1000)+'in')
	} else {
		svg.setAttribute('height',json.height+''+json.unit)
		svg.setAttribute('width',json.width+''+json.unit)
	}
	svg.setAttribute('viewBox','0 0 '+json.width+' '+json.height)
	// add info
	var svg_title = document.createElementNS(svgNS,'title');
	svg_title.textContent = json.name;
	svg.appendChild(svg_title);
	// add copper and silkscreen layers
	layers_desc = [ { name: 'copper', stroke: 'black', fill: 'black', display: 'inline'},
	                { name: 'drill', stroke: 'none', fill: 'white', display: 'inline'},
	                { name: 'clearance', stroke: 'red', fill: 'none', display: 'none'},
	                { name: 'soldermask', stroke: 'green', fill: 'none', display: 'none'},
	                { name: 'silkscreen', stroke: 'gray', fill: 'none', display: 'inline'}
	]
	layers = []
	for (var layer_i in layers_desc) {
		var layer_desc = layers_desc[layer_i]
		var layer = document.createElementNS(svgNS,'g')
		layer.setAttribute('name',layer_desc.name)
		layer.setAttribute('inkscape:groupmode','layer')
		layer.setAttribute('inkscape:label',layer_desc.name)
		layer.setAttribute('display',layer_desc.display)
		layer.style.setProperty('stroke',layer_desc.stroke)
		layer.style.setProperty('fill',layer_desc.fill)
		svg.appendChild(layer)
		layers[layer_desc.name] = layer
	}
	for (var element_i in json.elements) {
		var element = json.elements[element_i]
		switch (element.type) {
			case 'line':
				var line = document.createElementNS(svgNS,'line')
				line.style.setProperty('stroke-width',element.thickness)
				if (element.round) {
					line.style.setProperty('stroke-linecap','round')
				} else {
					line.style.setProperty('stroke-linecap','square')
				}
				line.setAttribute('x1',element.x1)
				line.setAttribute('y1',element.y1)
				line.setAttribute('x2',element.x2)
				line.setAttribute('y2',element.y2)
				layers['silkscreen'].appendChild(line)
				break
			case 'arc':
				element.start = element.start % 360
				element.stop = element.stop % 360
				var arc = null
				if (element.start==element.stop) {
					arc = document.createElementNS(svgNS,'circle')
					arc.setAttribute('cx',element.x)
					arc.setAttribute('cy',element.y)
					arc.setAttribute('r',element.radius)
				} else {
					arc = document.createElementNS(svgNS,'path')
					arc.setAttribute('d',"M "+(element.x+element.radius*Math.cos(((-1*element.start)%360)/360.0*Math.PI*2))+" "+(element.y-element.radius*Math.sin(((-1*element.start)%360)/360.0*Math.PI*2))+" A "+element.radius+" "+element.radius+" 0 "+((element.angle)%360>180 ? "1" : "0")+" 1 "+(element.x+element.radius*Math.cos(((-1*(element.start+element.angle))%360)/360.0*Math.PI*2))+" "+(element.y-element.radius*Math.sin(((-1*(element.start+element.angle))%360)/360.0*Math.PI*2))+" ")
				}
				arc.style.setProperty('stroke-width',element.thickness)
				if (element.round) {
					arc.style.setProperty('stroke-linecap','round')
				} else {
					arc.style.setProperty('stroke-linecap','square')
				}
				layers['silkscreen'].appendChild(arc)
				break
			case 'pad':
				var copper = document.createElementNS(svgNS,'line')
				copper.style.setProperty('stroke-width',element.thickness)
				if (element.round) {
					copper.style.setProperty('stroke-linecap','round')
				} else {
					copper.style.setProperty('stroke-linecap','square')
				}
				copper.setAttribute('x1',element.x1)
				copper.setAttribute('y1',element.y1)
				copper.setAttribute('x2',element.x2)
				copper.setAttribute('y2',element.y2)
				layers['copper'].appendChild(copper)
				var clearance = document.createElementNS(svgNS,'line')
				clearance.style.setProperty('stroke-width',element.thickness+2*element.clearance)
				if (element.round) {
					clearance.style.setProperty('stroke-linecap','round')
				} else {
					clearance.style.setProperty('stroke-linecap','square')
				}
				clearance.setAttribute('x1',element.x1)
				clearance.setAttribute('y1',element.y1)
				clearance.setAttribute('x2',element.x2)
				clearance.setAttribute('y2',element.y2)
				layers['clearance'].appendChild(clearance)
				var soldermask = document.createElementNS(svgNS,'line')
				soldermask.style.setProperty('stroke-width',element.soldermask)
				if (element.round) {
					soldermask.style.setProperty('stroke-linecap','round')
				} else {
					soldermask.style.setProperty('stroke-linecap','square')
				}
				soldermask.setAttribute('x1',element.x1)
				soldermask.setAttribute('y1',element.y1)
				soldermask.setAttribute('x2',element.x2)
				soldermask.setAttribute('y2',element.y2)
				layers['soldermask'].appendChild(soldermask)
				break
			case 'pin':
				var copper = document.createElementNS(svgNS,'rect')
				copper.style.setProperty('stroke-width',0)
				copper.setAttribute('x',element.x-element.thickness/2)
				copper.setAttribute('y',element.y-element.thickness/2)
				copper.setAttribute('height',element.thickness)
				copper.setAttribute('width',element.thickness)
				if (element.round) {
					copper.setAttribute('rx',element.thickness/2)
					copper.setAttribute('ry',element.thickness/2)
				} else {
					copper.setAttribute('rx',0)
					copper.setAttribute('ry',0)
				}
				layers['copper'].appendChild(copper)
				var drill = document.createElementNS(svgNS,'rect')
				drill.style.setProperty('stroke-width',0)
				drill.setAttribute('x',element.x-element.drill/2)
				drill.setAttribute('y',element.y-element.drill/2)
				drill.setAttribute('height',element.drill)
				drill.setAttribute('width',element.drill)
				if (element.round) {
					drill.setAttribute('rx',element.drill/2)
					drill.setAttribute('ry',element.drill/2)
				} else {
					drill.setAttribute('rx',0)
					drill.setAttribute('ry',0)
				}
				layers['drill'].appendChild(drill)
				var clearance = document.createElementNS(svgNS,'rect')
				clearance.style.setProperty('stroke-width',0)
				clearance.setAttribute('x',element.x-element.thickness/2-element.clearance)
				clearance.setAttribute('y',element.y-element.thickness/2-element.clearance)
				clearance.setAttribute('height',element.thickness+element.clearance*2)
				clearance.setAttribute('width',element.thickness+element.clearance*2)
				if (element.round) {
					clearance.setAttribute('rx',element.thickness/2+element.clearance)
					clearance.setAttribute('ry',element.thickness/2+element.clearance)
				} else {
					clearance.setAttribute('rx',0)
					clearance.setAttribute('ry',0)
				}
				layers['clearance'].appendChild(clearance)
				var soldermask = document.createElementNS(svgNS,'rect')
				soldermask.style.setProperty('stroke-width',0)
				soldermask.setAttribute('x',element.x-element.soldermask/2)
				soldermask.setAttribute('y',element.y-element.soldermask/2)
				soldermask.setAttribute('height',element.soldermask)
				soldermask.setAttribute('width',element.soldermask)
				if (element.round) {
					soldermask.setAttribute('rx',element.soldermask/2)
					soldermask.setAttribute('ry',element.soldermask/2)
				} else {
					soldermask.setAttribute('rx',0)
					soldermask.setAttribute('ry',0)
				}
				layers['soldermask'].appendChild(soldermask)
				break
			default:
				console.log("unknown element type: "+element.type)
		}
	}
	return svg
}

// convert CuVoodoo Land Pattern JSON to gEDA pcb footprint
function json2pcb(json) {
	// create file and add info
	var pcb = ''
	pcb += '# footprint generated from CuVoodoo Land Pattern\n'
	pcb += '# author: '+json.author+'\n'
	pcb += '# version: '+json.version+'\n'
	pcb += '# date: '+json.date+'\n'
	pcb += 'Element["" "'+json.name+'" "" "" 0 0 0 0 0 100 ""]\n'
	pcb += '(\n'
	// add element parts
	for (var element_i in json.elements) {
		var element = json.elements[element_i]
		switch (element.type) {
			case 'line':
				pcb += 'ElementLine['+element.x1+''+json.unit+' '+element.y1+''+json.unit+' '+element.x2+''+json.unit+' '+element.y2+''+json.unit+' '+element.thickness+''+json.unit+']\n'
				break
			case 'arc':
				pcb += 'ElementArc['+element.x+''+json.unit+' '+element.y+''+json.unit+' '+element.radius+''+json.unit+' '+element.radius+''+json.unit+' '+((((180-element.start)%360)+360)%360)+' '+(-1*(element.angle))+' '+element.thickness+''+json.unit+']\n'
				break
			case 'pad':
				pcb += 'Pad['+element.x1+''+json.unit+' '+element.y1+''+json.unit+' '+element.x2+''+json.unit+' '+element.y2+''+json.unit+' '+element.thickness+''+json.unit+' '+element.clearance*2+''+json.unit+' '+element.soldermask+''+json.unit+' "" "'+element.number+'" "'
				if (!element.round) {
					pcb += 'square'
				}
				pcb += '"]\n'
				break
			case 'pin':
				pcb += 'Pin['+element.x+''+json.unit+' '+element.y+''+json.unit+' '+element.thickness+''+json.unit+' '+element.clearance*2+''+json.unit+' '+element.soldermask+''+json.unit+' '+element.drill+''+json.unit+' "" "'+element.number+'" "'
				if (!element.round) {
					pcb += 'square'
				}
				pcb += '"]\n'
				break
			default:
				console.log("unknown element type: "+element.type)
		}
	}
	pcb += ')\n'
	return pcb
}

//  convert CuVoodoo Land Pattern JSON to KiCad s-expression footprint module/file
function json2kicad(json) {
	// create file and add info
	var kicad = ''
	kicad += '# footprint generated from CuVoodoo Land Pattern\n'
	kicad += '# author: '+json.author+'\n'
	kicad += '# version: '+json.version+'\n'
	kicad += '# date: '+json.date+'\n'
	kicad += '(module "'+json.name+'" (layer F.Cu)\n'
	// add element parts
	for (var element_i in json.elements) {
		var element = json.elements[element_i]
		switch (element.type) {
			case 'line':
				kicad += '(fp_line (start '+convert_unit(element.x1,json.unit,"mm")+' '+convert_unit(element.y1,json.unit,"mm")+') (end '+convert_unit(element.x2,json.unit,"mm")+' '+convert_unit(element.y2,json.unit,"mm")+') (layer F.SilkS) (width '+convert_unit(element.thickness,json.unit,"mm")+'))\n'
				break
			case 'arc':
				kicad += '(fp_arc (start '+convert_unit(element.x,json.unit,"mm")+' '+convert_unit(element.y,json.unit,"mm")+') (end '+convert_unit((element.x+element.radius*Math.cos(((-1*element.start)%360)/360.0*Math.PI*2)),json.unit,"mm")+' '+convert_unit((element.y-element.radius*Math.sin(((-1*element.start)%360)/360.0*Math.PI*2)),json.unit,"mm")+') (angle '+element.angle+') (layer F.SilkS) (width '+convert_unit(element.thickness,json.unit,"mm")+'))\n'
				break
			case 'pad':
				var x = (element.x1+element.x2)/2
				var y = (element.y1+element.y2)/2
				var length = Math.sqrt(Math.pow(element.x2-element.x1,2)+Math.pow(element.y2-element.y1,2))
				var angle = Math.atan2(element.y2-element.y1,element.x2-element.x1)*180/Math.PI;
				kicad += '(pad "'+element.number+'" smd '
				if (element.round) {
					kicad += 'oval'
				} else {
					kicad += 'rect'
				}
				kicad += ' (at '+convert_unit(x,json.unit,"mm")+' '+convert_unit(y,json.unit,"mm")+' '+angle+')'
				kicad += ' (size '+convert_unit(length,json.unit,"mm")+' '+convert_unit(element.thickness,json.unit,"mm")+')'
				kicad += ' (layers F.Cu F.Paste F.Mask)'
				kicad += ' (clearance '+convert_unit(element.clearance,json.unit,"mm")+')'
				kicad += ' (solder_mask_margin '+convert_unit((element.thickness/2*-1+element.soldermask),json.unit,"mm")+')'
				kicad += ')\n'
				break
			case 'pin':
				break
			default:
				console.log("unknown element type: "+element.type)
		}
	}
	kicad += ')\n'
	return kicad
}