import DI, {DDNames} from "@gongt/ts-stl-library/DI";
import {RequestHandler, Response} from "express-serve-static-core";
import * as ServeStatic from "serve-static";
import {ServeStaticOptions} from "serve-static";

export type ServeStaticEx = ServeStaticOptions&StaticCORSOptions;

export interface StaticCORSOptions {
	cors?: boolean;
	methods?: string[];
	debugMode?: boolean;
}

export function createServeStatic(fsPath: string, options: ServeStaticEx = {}): RequestHandler {
	const resHeader: any = {
		// 'Access-Control-Allow-Origin': origins,
		// 'Access-Control-Expose-Headers': '',
		'Access-Control-Max-Age': 3600, // only access control cache time
		// 'Access-Control-Allow-Credentials': '',
		// 'Access-Control-Allow-Headers': '',
	};
	const isDebug = options.hasOwnProperty('debugMode')? options.debugMode : DI.get(DDNames.isDebugMode);
	if (isDebug) {
		resHeader['Cache-Control'] = 'must-revalidate';
	}
	
	if (options.cors) {
		// TODO: cors
		resHeader['Access-Control-Allow-Origin'] = '*';
		if (options.methods) {
			resHeader['Access-Control-Allow-Methods'] = options.methods.join(', ');
		} else {
			resHeader['Access-Control-Allow-Methods'] = '*';
		}
	}
	
	const custom = options.setHeaders;
	if (custom) {
		options.setHeaders = (res: Response, path: string, stat: any) => {
			res.header(resHeader);
			custom(res, path, stat);
		};
	} else {
		options.setHeaders = (res: Response) => res.header(resHeader);
	}
	
	if (/npm_modules|jspm_modules/.test(fsPath)) {
		if (!options.hasOwnProperty('maxAge')) {
			options.maxAge = isDebug? '1h' : '7d';
		}
		if (!options.hasOwnProperty('etag')) {
			options.etag = true;
		}
	} else {
		if (!options.hasOwnProperty('maxAge')) {
			options.maxAge = isDebug? '0' : '1d';
		}
		if (!options.hasOwnProperty('etag')) {
			options.etag = true;
		}
	}
	
	if (!options.hasOwnProperty('fallthrough')) {
		options.fallthrough = false;
	}
	
	return ServeStatic(
		fsPath,
		options,
	);
}