#!/usr/bin/env node
'use strict';

const fs = require('fs');
const yargs = require('yargs');

const args = yargs
    .option('json', {
        alias: 'j',
        description: 'Exports the license information into ./licenses.json as json.',
        type: 'boolean',
    })
	.option('pretty', {
        alias: 'p',
        description: 'Prettify the json output.',
        type: 'boolean',
    })
	.option('markdown', {
        alias: 'm',
        description: 'Exports the license information into ./licenses.md as markdown.',
        type: 'boolean',
    })
	.option('recursive', {
        alias: 'r',
        description: 'Include all of the dependencies\' subdependencies.',
        type: 'boolean',
    })
	.option('output', {
		alias : 'o',
		describe: 'Output folder for the exports (Default: Current folder).',
		type: 'string',
		default: '.'
	})
	.option('input', {
		alias : 'i',
		describe: 'Path to the input folder containing your package.json and node_modules (Default: Current folder).',
		type: 'string',
		default: '.'
	})
    .help()
    .alias('help', 'h')
	.alias('v', 'version')
    .argv;

function parsePackageInfo(path) {
	const packagecontents = JSON.parse(fs.readFileSync(path, { encoding: 'utf-8' }));
	packagecontents.dependencies = Object.entries(packagecontents.dependencies || {});
	packagecontents.devDependencies = Object.entries(packagecontents.devDependencies || {});
	return packagecontents;
}

function mergeDependencies(packageInfo) {
	return [].concat(packageInfo.dependencies, packageInfo.devDependencies);
}

function getDependencyLicenseInfo(all_dependencies, recursive) {
	let all = [];

	all_dependencies.forEach((p) => {
		const packageinfo = parsePackageInfo(`${args.input}/node_modules/${p[0]}/package.json`);
		let licensetext = '';
		if (fs.existsSync(`${args.input}/node_modules/${p[0]}/LICENSE.md`)) {
			licensetext = fs.readFileSync(`${args.input}/node_modules/${p[0]}/LICENSE.md`, { encoding: 'utf-8' });
		}
		if (fs.existsSync(`${args.input}/node_modules/${p[0]}/LICENSE`)) {
			licensetext = fs.readFileSync(`${args.input}/node_modules/${p[0]}/LICENSE`, { encoding: 'utf-8' });
		}
		if (fs.existsSync(`${args.input}/node_modules/${p[0]}/LICENSE.txt`)) {
			licensetext = fs.readFileSync(`${args.input}/node_modules/${p[0]}/LICENSE.txt`, { encoding: 'utf-8' });
		}
		const info = {
			author: packageinfo.author,
			repo: packageinfo.repository || packageinfo.repository.url,
			description: packageinfo.description,
			name: packageinfo.name,
			license: packageinfo.license,
			licensetext
		};
		all.push(info);
		if (recursive == true) {
			all.push(...getDependencyLicenseInfo(packageinfo.dependencies, true));
		}
	});
	return all;
}
const packageInfo = parsePackageInfo(`${args.input}/package.json`);
const all = getDependencyLicenseInfo(mergeDependencies(packageInfo), args.recursive);

if (args.json) {
	if (args.pretty) {
		fs.writeFileSync((args.output+'/licenses.json'), JSON.stringify(all, null, 4));
	} else {
		fs.writeFileSync((args.output+'/licenses.json'), JSON.stringify(all));
	}
}
if (args.markdown) {
	fs.writeFileSync((args.output+'/licenses.md'), '');
	all.forEach((p) => {
		fs.appendFileSync(
			(args.output+'/licenses.md'),
			`# ${p.name}\n**Author**: ${p.author}\n**Repo**: ${p.repo}\n**License**: ${p.license}\n**Description**: ${p.description}\n## License Text\n${p.licensetext} \n\n`
		);
	});
} else {
	return all;
}