import {  Resvg } from "@resvg/resvg-js";
import { promises } from "fs";
import { JSDOM } from "jsdom";
import * as d3 from "d3";
import yargs from "yargs/yargs";
import { hideBin } from "yargs/helpers";
import spawn from "await-spawn";
import random from "random";

const xmlns = "http://www.w3.org/2000/xmlns/";
const xlinkns = "http://www.w3.org/1999/xlink";
const svgns = "http://www.w3.org/2000/svg";

import {RADIUS_OPTS, RADIUS_DESC, DotMaker} from './src/components/dots.js';
import {PALETTES, ColourNamer} from './src/components/palettes.js';

const CELL = 10;
const MAG = 2;
const WIDTH = 20;
const HEIGHT = WIDTH;
const VISIBLE_DOG = 1000;

function randomise_params() {
	const palette_name = random.choice(Array.from(PALETTES.keys()));
	const palette_fn = PALETTES.get(palette_name);
	const palette = palette_fn();
	const patterns = [1,2].map((n) => { return {
		i: n,
		colour: palette[n],
		m: random.choice([1, 2, 3, 4, 5]),
		n: random.choice([1, 2, 3, 4, 5]),
		f: random.choice(RADIUS_OPTS),
		r: random.float(0, 0.4),
	}});
	return {
		background: palette[0],
		palette: palette_name,
		patterns: patterns
	}
}


// lol the best way I found to to this was imagemagick!

async function get_histogram(imgfile) {
	try {
		const bl = await spawn('convert', [ imgfile, '-format', '%c', 'histogram:info:' ]);
		return parse_histogram(bl.toString());
	} catch (e) {
		console.log(e);
	}
}


function parse_histogram(convert_out) {
	const colour_re = /(\d+): \(\d+,\d+,\d+,\d+\) (#[A-F0-9]+) /;
	const colours = new Map();
	convert_out.split("\n").forEach((l) => {
		const m = l.match(colour_re);
		if( m ) {
			const colour = m[2].substring(0, 7);
			colours.set(colour, Number(m[1]));
		}
	});
	return new Map([...colours].sort((a, b) => b[1] - a[1]));
}


function colour_visible(hist, colour) {
	const hexcolour = colour.formatHex().toUpperCase();
	return hist.get(hexcolour) > VISIBLE_DOG;
}


function image_description(namer, params, histogram) {
	const colours = [
		params.background,
		params.patterns[0].colour,
		params.patterns[1].colour,
	];
	const i_vis = [0, 1, 2].filter((i) => colour_visible(histogram, colours[i]));
	const named_colours = i_vis.map((i) => namer.colour_to_text(colours[i]));
	const gradients = i_vis.map((i) => {
		if( i > 0 ) {
			return RADIUS_DESC[params.patterns[i - 1].f];
		} else {
			return '';
		}
	});
	if( named_colours.length == 1 ) {
		return `A solid field of ${named_colours[0]}`;
	}
	if( named_colours.length > 1 ) {
		const bgc = named_colours[0];
		const a = bgc.match(/^[aeiou]/) ? 'an' : 'a';
		const dot_desc = named_colours.slice(1);
		const gs = gradients.slice(1);
		const pattern_desc = dot_desc.map((d, i) => `${d} dots ${gs[i]}`); 
		const patterns = pattern_desc.join(' and ');
		return `A pattern of ${patterns} on ${a} ${bgc} background`;
	}
	return "";
}


function poptimal_svg(params) {
	const window = new JSDOM().window;
	const document = window.document;
	const container = d3.select(document.body).append("div");

	const dm = new DotMaker(WIDTH);

	const svg = container.append("svg")
	  .attr("width", WIDTH * CELL * MAG)
	  .attr("height", HEIGHT * CELL * MAG)
	  .attr("viewBox", [ 0, 0, WIDTH, HEIGHT ]);

	const background = svg.append("rect")
	  .attr("x", 0)
	  .attr("y", 0)
	  .attr("width", WIDTH)
	  .attr("height", WIDTH)
	  .attr("fill", params.background);


	params.patterns.map((p) =>  {
		const dots = dm.dots(1 / p.m, p.n);
		const dots_g = svg.append("g")
	  			.attr("id", `dots${p.i}`);
	
		dots_g.selectAll("circle")
		  .data(dots)
		  .join("circle")
		  .attr("r", (d) => dm.radius(d, p.f, p.r))
		  .attr("fill", p.colour)
		  .attr("cx", (d) => d.x)
		  .attr("cy", (d) => d.y);
	});
 
	const node = svg.node();

  	node.setAttributeNS(xmlns, "xmlns", svgns);
  	node.setAttributeNS(xmlns, "xmlns:xlink", xlinkns);
  	const serializer = new window.XMLSerializer;
  	return serializer.serializeToString(node);

}


async function post_image(image, alt_text, cf) {
	const status_url = `${cf.base_url}/api/v1/statuses`;
	const media_url = `${cf.base_url}/api/v1/media`;
	const headers = {
		'Authorization': `Bearer ${cf.access_token}`,
	};
	const rawData = await promises.readFile(image);
	const blob = new Blob([rawData]);
	const fd = new FormData();
	fd.set('description', alt_text);
	fd.set('file', blob, image, 'text/png');
	const resp = await fetch(media_url, {
		method: 'POST',
		headers: headers,
		body: fd
	});

	const bodyjson = await resp.text();
	const response = JSON.parse(bodyjson);
	const media_id = response["id"];

	headers['Accept'] = 'application/json';
	headers['Content-Type'] = 'application/json';
	const resp2 = await fetch(status_url, {
		method: 'POST',
		headers: headers,
		body: JSON.stringify({ media_ids: [ media_id ] })
	});
	const bodyjson2 = await resp2.text();

}


async function main() {
	const argv = yargs(hideBin(process.argv))
		.usage("Usage: -s SIZE -o output.png -c config.json")
		.default('s', 1200)
		.default('c', 'config.json').argv;

	const cfjson = await promises.readFile(argv.c);
  	const cf = JSON.parse(cfjson);



  	const fn = argv.o || String(Date.now()) + '.png';

  	const imgfile = cf['working_dir'] + '/' + fn;

	const params = randomise_params();
	const colourf = params.palette === 'grayscale' ? cf['grayscale'] : cf['colour'];

	const namer = new ColourNamer();
	await namer.load_colours(colourf);


	const svg = poptimal_svg(params);
	const opts = {
    	background: 'rgba(255, 255, 255, 1.0)',
    	fitTo: {
      		mode: 'width',
      		value: argv.s,
    	},
    };

  	const resvg = new Resvg(svg, opts);
 	const pngData = resvg.render();
  	const pngBuffer = pngData.asPng();


  	await promises.writeFile(imgfile, pngBuffer);

  	// generate the alt_text last to check the image file histogram
  	// so we don't include obscured colours
  	const hist = await get_histogram(imgfile);
	const alt_text = image_description(namer, params, hist);

	console.log(alt_text);
	console.log(imgfile);
  	if( cf['base_url'] ) {
  		await post_image(imgfile, alt_text, cf);
  	}
}



main();