/* This script operates asynchronously. It can be written synchronously, but
 * not a lot is saved once you try-catch everything. Uses the co module. On
 * node 0.11.2+ with the --harmony flag generators are available. This
 * version uses Co, which requires generators.
 *
 * MIT licence.
 */
var path = require('path');
var co = require('co');
var fs = require('co-fs');


// Write the pre-commit script.
function* writePreCommit() {
	'use strict';

	var filename = path.join(__dirname, '.git', 'hooks', 'pre-commit');
	var content = 'npm test';

	var write = yield fs.writeFile(filename, content);
	var chmod = yield fs.chmod(filename, '755');

	return [write, chmod];
}

// Write the hook scripts in parallel.
function* writeHooks() {
	'use strict';

	// Stack more hook writers in here to write them in parallel.
	return yield [
		co(writePreCommit)
	];
}

// Check that the hooks directory exists and write the hooks.
function* execute() {
	'use strict';

	var stat = yield fs.stat(path.join(__dirname, '.git', 'hooks'));

	if (!stat.isDirectory()) {
		console.log('No git directory found. Hooks will not be installed.');
		return process.exit(0);
	}

	var hooks = yield co(writeHooks);

	return [stat, hooks];
}

// Execuse the writehoos.
co(execute)(function (err) {
	'use strict';

	if (err) {
		console.error(err);
		return process.exit(1);
	}

	console.log('Git hooks installed');
	process.exit(0);
});