const http = require('http');
const https = require('https');
const { URL } = require('url');
const { join } = require('path');
const { stringify } = require('querystring');
const { createGunzip, createInflate } = require('zlib');

const c = [ 'gzip', 'deflate' ];
const common = [ 'GET', 'HEAD', 'POST', 'PUT', 'DELETE', 'CONNECT', 'OPTIONS', 'TRACE', 'PATCH' ];
const { version } = require('../package.json');

const WumpResponse = class WumpResponse {
	constructor (res) {
		this.body = Buffer.alloc(0);
		this.coreRes = res;

		this.headers = res.headers;
		this.statusCode = res.statusCode;
	}

	_addChunk (chunk) {
		this.body = Buffer.concat([ this.body, chunk ]); 
	}

	text () {
		return this.body.toString();
	}
	
	json () {
		return JSON.parse(this.body);
	}
};

const WumpRequest = class WumpRequest {
	constructor (url = {}, method = {}) {
		const o = (typeof url === 'string' ? method : url);
		const obj = (typeof o === 'object');

		if (typeof url !== 'string' && !o.hasOwnProperty('url')) {
			throw new Error('Missing url parameter');
		}

		this.o = {
			'm': typeof o === 'string' ? o : obj && o.method ? o.method : 'GET',
			'url': typeof url === 'string' ? new URL(url) : obj && typeof o.url === 'string' ? new URL(o.url) : url,
			'SDA': obj && typeof o.sendDataAs === 'string' ? o.sendDataAs : obj && o.data && typeof o.data === 'object' ? 'json' : undefined,
			'data': obj && o.data ? o.data : obj && o.json ? o.json : obj && o.form ? stringify(o.form) : undefined,
			'parse': obj && o.parse ? o.parse : undefined,
			'follow': !!(obj && o.followRedirects),
			'rHeaders': obj && typeof o.headers === 'object' ? o.headers : {},
			'streamed': !!(obj && o.streamed),
			'compressed': !!(obj && o.compressed),
			'timeoutTime': obj && typeof o.timeout === 'number' ? o.timeout : null,
			'coreOptions': obj && typeof o.coreOptions === 'object' ? o.coreOptions : {}
		};

		if (typeof o.core === 'object') {
			Object.keys(o.core).forEach((v) => this.option(v, o.core[v]));
		}

		return this;
	}

	query (a, b) {
		if (typeof a === 'object') Object.keys(a).forEach((v) => this.o.url.searchParams.append(v, a[v]));
		else this.o.url.searchParams.append(a, b);

		return this;
	}

	body (data, SA) {
		this.o.SDA = typeof data === 'object' && !SA && !Buffer.isBuffer(data) ? 'json' : (SA ? SA.toLowerCase() : 'buffer');
		this.o.data = this.SDA === 'form' ? stringify(data) : (this.SDA === 'json' ? JSON.stringify(data) : data);

		return this;
	}

	header (a, b) {
		if (typeof a === 'object') Object.keys(a).forEach((v) => this.o.rHeaders[v.toLowerCase()] = a[v]);
		else this.o.rHeaders[a.toLowerCase()] = b;

		return this;
	}

	compress () {
		this.compressed = true;
		if (!this.o.rHeaders['accept-encoding']) this.o.rHeaders['accept-encoding'] = c.join(', ');

		return this;
	}
	
	path (p) {
		this.o.url.pathname = join(this.o.url.pathname, p);

		return this;
	}
	
	stream () {
		this.o.streamed = true;
		
		return this;
	}

	option (n, v) {
		this.o.coreOptions[n] = v;
		
		return this;
	}
	timeout (timeout) {
		this.o.timeoutTime = timeout;
		
		return this;
	}

	send () {
		return new Promise((resolve, reject) => {
			if (this.o.data) {
				if (!this.o.rHeaders.hasOwnProperty('user-agent')) {
					this.o.rHeaders['User-Agent'] = w.userAgent;
				}
				
				if (this.o.SDA === 'json' && !this.o.rHeaders.hasOwnProperty('content-type')) this.o.rHeaders['Content-Type'] = 'application/json';
				if (this.o.SDA === 'form') {
					if (!this.o.rHeaders.hasOwnProperty('content-type')) this.o.rHeaders['Content-Type'] = 'application/x-www-form-urlencoded';
					if (!this.o.rHeaders.hasOwnProperty('content-length')) this.o.rHeaders['Content-Length'] = Buffer.byteLength(this.o.data);
				}
			}

			let req;
			const options = {
				'host': this.o.url.hostname,
				'port': this.o.url.port,
				'path': this.o.url.pathname + this.o.url.search,
				'method': this.o.m,
				'headers': this.o.rHeaders,
				'protocol': this.o.url.protocol,
				...this.o.coreOptions
			}

			const handler = async (res) => {
				let stream = res;

				if (this.o.compressed) {
					if (res.headers['content-encoding'] === 'gzip') stream = res.pipe(createGunzip());
					else if (res.headers[ 'content-encoding'] === 'deflate') stream = res.pipe(createInflate());
				}

				let wumpRes;

				if (this.o.streamed) resolve(stream);
				else {
					wumpRes = new WumpResponse(res);

					if (res.headers.hasOwnProperty('location') && this.o.follow) {
						this.o.url = (new URL(res.headers['location'], this.o.url)).toString();
						return await module.exports(this.o);
					}

					stream.on('error', (e) => reject(e));
					stream.on('data', (c) => wumpRes._addChunk(c));
					stream.on('end', () => {
						if (this.o.parse) {
							if (this.o.parse === 'json') wumpRes.body = JSON.parse(wumpRes.body);
							else if (this.o.parse === 'text') wumpRes.body = wumpRes.body.toString();
							else wumpRes.body = wumpRes.body;
						}
						
						resolve(wumpRes);
					});
				}
			};

			if (this.o.url.protocol === 'http:') req = http.request(options, handler);
			else if (this.o.url.protocol === 'https:') req = https.request(options, handler);
			else throw new Error(`Bad URL protocol: ${this.o.url.protocol}`);


			if (this.o.timeoutTime) {
				req.setTimeout(this.o.timeoutTime, () => {
					req.abort();
					if (!this.o.streamed) reject(new Error('Timeout reached'));
				});
			}

			req.on('error', (e) => reject(e));

			if (this.o.data) {
				if (this.o.SDA === 'json') {
					req.write(JSON.stringify(this.o.data));
				} else {
					if (typeof this.o.data === 'object') {
						req.write(JSON.stringify(this.o.data));
					} else {
						req.write(this.o.data);
					}
				}
			}
			
			req.end();
		});
	}
};

module.exports = (url, method) => {
  return new WumpRequest(url, method);
};

common.forEach((v) => {
  module.exports[v.toLowerCase()] = (url, method) => {
    if (typeof url === 'string') {
      return new WumpRequest(url, { method: v, ...method });
    } else {
      return new WumpRequest({ method: v, ...url }, method);
    }
  }
});

module.exports.version = version;
module.exports.userAgent = `wumpfetch/${version} (https://github.com/PassTheWessel/wumpfetch)`;