define bezierCubic2Q2 [require 'node-sfnt/lib/math/bezierCubic2Q2']
define tp [require './transform'].transformPoint
define Stroke [require './stroke'].Stroke

define id (
	.xx 1
	.yx 0
	.xy 0
	.yy 1
	.x 0
	.y 0
)

define [Glyph name] : begin {
	set this.name name
	set this.unicode ()
	set this.contours ()
	set this.advanceWidth 500
	set this.gizmo (
		.xx 1
		.yx 0
		.xy 0
		.yy 1
		.x 0
		.y 0
	)
	return nothing
}
define [Glyph.prototype.set-width w] : begin {
	this.advanceWidth = w
	return this
}
define [Glyph.prototype.assign-unicode u] : begin {
	this.unicode.push : piecewise {
		[[typeof u] === 'string'] : u.charCodeAt 0
		true u 
	}
	return this
}

define [Glyph.prototype.start-from x y] : begin {
	this.contours.push ([tp this.gizmo (.x x .y y .onCurve true)])
	return this
}
define [Glyph.prototype.line-to x y] : begin {
	this.contours`[this.contours.length - 1].push [tp this.gizmo (.x x .y y .onCurve true)]
	return this
}
define [Glyph.prototype.curve-to xc yc x y] : begin {
	this.contours`[this.contours.length - 1].push [tp this.gizmo (.x xc .y yc .onCurve false)] [tp this.gizmo (.x x .y y .onCurve true)]
	return this
}
define [Glyph.prototype.cubic-to x1 y1 x2 y2 x y] : begin {
	local lastContour this.contours`[this.contours.length - 1]
	local lastPoint lastContour`[lastContour.length - 1]
	local segments [bezierCubic2Q2 lastPoint (.x x1 .y y1) (.x x2 .y y2) (.x x .y y)]
	foreach (p0 (.x xc .y yc) (.x xf .y yf)) [items-of segments] : this.curve-to xc yc xf yf
	return this
}
define [Glyph.prototype.reverse-last] : begin {
	this.contours.[this.contours.length - 1] = [this.contours.[this.contours.length - 1].reverse]
}
define [Glyph.prototype.put-shapes contours] : begin {
	# do not double-transform
	local t this.gizmo
	set this.gizmo id
	foreach contour [items-of contours] : begin {
		this.start-from contour.0.x contour.0.y
		for [local j 1] [j < contour.length] [inc j] : begin {
			local point contour`j
			if point.cubic [begin {
				local p2 contour`[j + 1]
				local p3 contour`[j + 2]
				this.cubic-to point.x point.y p2.x p2.y p3.x p3.y
				j = j + 2
			}] [if point.onCurve [this.line-to point.x point.y] [begin {
				local p2 contour`[j + 1]
				this.curve-to point.x point.y p2.x p2.y
				j = j + 1
			}]]
		}
	}
	set this.gizmo t
	return this
}
define [Glyph.prototype.include-glyph glyph] : this.put-shapes glyph.contours
define [Glyph.prototype.create-stroke] : begin {
	local s : new Stroke
	s.gizmo = [Object.create this.gizmo]
	return s
}

exports.Glyph = Glyph