export default new class {
	grid(canvas = false, removeOld = true) {
		if (removeOld) {
			canvas.getObjects().forEach(g => g._isGrid ? canvas.remove(g) : '');
		}

		const width = canvas.width / canvas.getZoom();
		const height = canvas.height / canvas.getZoom();
		const step = 30;

		const lines = [];
		const addLine = (i, to) => {
			let coords = [i * step, 0, i * step, height];
			if (to == 'y') {
				coords = [0, i * step, width, i * step];
			}

			lines.push(new fabric.Line(coords, {
				fill: '#000000',
				stroke: '#000000',
				strokeWidth: 1,
				selectable: false,
				evented: false,
			}));
		};

		new Array(Math.ceil(width / step)).fill(null).forEach((v, i) => addLine(i));
		new Array(Math.ceil(height / step)).fill(null).forEach((v, i) => addLine(i, 'y'));

		const group = new fabric.Group(lines, {
			selectable: false,
			evented: false,
			_isGrid: true,
			originX: 'left',
			originY: 'top'
		});

		if (this.gridObject) { canvas.remove(this.gridObject); }

		this.gridObject = group;
		this.gridObject._isGrid = true;

		return this.gridObject;
	}

	ruler(canvas = false, zoomOrigin = 1, removeOld = true, color = '#55606c') {
		if (removeOld) {
			canvas.getObjects().forEach(g => g.__tt == 'ruler' ? canvas.remove(g) : '');
		}

		let measure = 'px';
		const width = canvas.getWidth() / canvas.getZoom();
		const height = canvas.getHeight() / canvas.getZoom();

		let minDistance = (width * .1);
		if (minDistance < 20) minDistance = 20;

		const ruler = [];
		let correctDistance = correctDistance = width / 10;

		let zoom = canvas.getZoom();
		let font_size = 12 / zoom;
		let cwidth = canvas.getWidth() / canvas.getZoom();
		let cheight = canvas.getHeight() / canvas.getZoom();

		let bg_color = "rgba(231, 231, 231, 1)",
			measure_bg_size = 20/zoom


		//подложка линейки горизональной
		var measure_bg_w = new fabric.Rect({
			left: measure_bg_size, //делаем отступ что бы линейка не налаживалась
			top: cheight-measure_bg_size,
			fill: bg_color,
			width: cwidth,
			height: measure_bg_size
		});

		//подложка линейки вертикальной
		var measure_bg_h = new fabric.Rect({
			left: 0,
			top: 0,
			width: measure_bg_size,
			fill: bg_color,
			height: cheight
		});

		ruler.push(measure_bg_w);
		ruler.push(measure_bg_h);

		if(false){
			let measure_text = new fabric.Text(measure, {
				fill: color,
				left: 30 / zoom,
				top: 30 / zoom,
				fontSize: font_size,
				textBackgroundColor: bg_color
			});

			ruler.push(measure_text);
		}

		let prev_text_step = 0,
			prev_line = 0;

		for (let i = 0; i < height / correctDistance; i++) {
			const lineOpts = {
				fill: color,
				stroke: color,
				strokeWidth: 1 / zoom
			};

			let leftText = false;
			let txt = (measure == 'px') ? (`${Math.round((i * correctDistance) / zoomOrigin)}`) : `${i}`;

			if (txt != "0"){
				let text_step = (i * correctDistance);
				if (text_step - prev_line > (10 / zoom)) {
					if (text_step <= height - 1) {
						ruler.push(new fabric.Line([
							0, text_step,
							13 / zoom, text_step
						], lineOpts));
						prev_line = text_step;
					}
				}
				if (text_step - prev_text_step < (100 / zoom)) {
				} else {
					leftText = new fabric.Text(txt, {
						fill: color,
						left: 20 / zoom,
						top: (text_step) - (6 / zoom),
						fontSize: font_size,
						textBackgroundColor: bg_color
					});
					prev_text_step = text_step;
				}
			}

			const miniStep = (((i + 1) * correctDistance) - (i * correctDistance)) / 10;
			if (miniStep >= 2) {
				if (i * correctDistance <= height - 1) {
					const coords = new Array(9).fill(0).reduce((result, item, index) => {
						const left = (i * correctDistance) + ((index + 1) * miniStep);
						if (left + 1 <= height) {
							result.push(new fabric.Line([
								0, left,
								(index == 4 ? 8 : 5) / zoom, left,
							], lineOpts));
						}
						return result;
					}, []);
					ruler.push(...coords);
				}
			}
			if (leftText) {
				ruler.push(leftText);
			}
		}
		prev_text_step = 0;
		prev_line = 0;

		console.log("correctDistance", correctDistance, "full width", width);
		let center = width/2;
		for(let i=0; i<(width/correctDistance)/2; i++){
			let step_right = center+(i * correctDistance),
				step_left = center-(i * correctDistance);


//			ruler.push(new fabric.Line([
//				text_step,
//				cheight-(measure_bg_size-2),
//				text_step,
//				(cheight)
//			], lineOpts));
			console.log("draw segments", step_left, step_right );
		}


		//слева на право, внизу.
		for(let i = 0; i < width / correctDistance; i++){
			const lineOpts = {
				fill: color, stroke: color,
				strokeWidth: 1 / zoom
			};

			let txt = (measure == 'px') ? (`${Math.round((i * correctDistance) / zoomOrigin)}`) : `${i}`;
			let topText = false;
			if (txt != "0") {
				let text_step = (i * correctDistance);
				//рисуем большие полоски
				if (text_step - prev_line > (10 / zoom)) {
					if (text_step <= width - 1) {
						ruler.push(new fabric.Line([
							text_step,
							cheight-(measure_bg_size-2),
							text_step,
							(cheight)
						], lineOpts));
					}
					prev_line = text_step;
				}

				//height
				//рисуем текста
				if (text_step - prev_text_step > (100 / zoom)) {
//					topText = new fabric.Text(txt, {
//						fill: color,
//						left: (i * correctDistance),
//						top: cheight-(16 / zoom),
//						fontSize: font_size,
//						textBackgroundColor: bg_color
//					});
//					topText.set({
//						left: topText.left - (i == 0 ? 0 : (topText.width / 2))
//					});
					prev_text_step = text_step;
				}
			}

			//100

			//рисум маленькие полоски
			const miniStep = (((i + 1) * correctDistance) - (i * correctDistance)) / (10);
			if (miniStep >= 2) {
				if (i * correctDistance <= width - 1) {
					let prev_min = (i * correctDistance) + ((0 + 1) * miniStep);
					const coords = new Array(9).fill(0).reduce((result, item, index) => {
						const left = (i * correctDistance) + ((index + 1) * miniStep);
						let top = 100;
						let line_v_offset = measure_bg_size-2;
						if (left + 1 <= width) {
							let line_color = "red";
							if(index == 4){
								line_color = "blue";
							}
							//line
							lineOpts.fill = line_color;
							lineOpts.stroke = line_color;
							lineOpts.color = line_color

							result.push(new fabric.Line([
								left,
								cheight-line_v_offset, //top
								left,
								(index == 4 ? (cheight-(measure_bg_size/2)) : (cheight-(measure_bg_size/1.5))) / zoom //height
							], lineOpts));
						}
						prev_min = left;
						return result;
					}, []);
					ruler.push(...coords);
				}
			}
			if (topText) {
				ruler.push(topText);
			}
		}

		return new fabric.Group(ruler, {
			measure: measure,
			// objectCaching: true,
			hoverCursor: 'default',
			__tt: 'ruler',
			selectable: false,
			evented: false,
		})
	}
}