/*!
 * Nodeunit
 * Copyright (c) 2010 Caolan McMahon
 * MIT Licensed
 *
 * THIS FILE SHOULD BE BROWSER-COMPATIBLE JS!
 * You can use @REMOVE_LINE_FOR_BROWSER to remove code from the browser build.
 * Only code on that line will be removed, it's mostly to avoid requiring code
 * that is node specific
 */

/**
 * Module dependencies
 */

var async    = require('../deps/async'), //@REMOVE_LINE_FOR_BROWSER
    nodeunit = require('./nodeunit'),    //@REMOVE_LINE_FOR_BROWSER
    types    = require('./types');       //@REMOVE_LINE_FOR_BROWSER


/**
 * Added for browser compatibility
 */

var _keys = function (obj) {
    if (Object.keys) {
        return Object.keys(obj);
    }
    var keys = [];
    for (var k in obj) {
        if (obj.hasOwnProperty(k)) {
            keys.push(k);
        }
    }
    return keys;
};


var _copy = function (obj) {
    var nobj = {};
    var keys = _keys(obj);
    for (var i = 0; i <  keys.length; i += 1) {
        nobj[keys[i]] = obj[keys[i]];
    }
    return nobj;
};


/**
 * Runs a test function (fn) from a loaded module. After the test function
 * calls test.done(), the callback is executed with an assertionList as its
 * second argument.
 *
 * @param {String} name
 * @param {Function} fn
 * @param {Object} opt
 * @param {Function} callback
 * @api public
 */

exports.runTest = function (name, fn, opt, callback) {
    var options = types.options(opt);

    options.testStart(name);
    var start = new Date().getTime();
    var test = types.test(name, start, options, callback);

    try {
        fn(test);
    }
    catch (e) {
        test.done(e);
    }
};

/**
 * Takes an object containing test functions or other test suites as properties
 * and runs each in series. After all tests have completed, the callback is
 * called with a list of all assertions as the second argument.
 *
 * If a name is passed to this function it is prepended to all test and suite
 * names that run within it.
 *
 * @param {String} name
 * @param {Object} suite
 * @param {Object} opt
 * @param {Function} callback
 * @api public
 */

exports.runSuite = function (name, suite, opt, callback) {
    suite = wrapGroup(suite);
    var keys = _keys(suite);

    async.concatSeries(keys, function (k, cb) {
        var prop = suite[k], _name;

        _name = name ? [].concat(name, k) : [k];
        _name.toString = function () {
            // fallback for old one
            return this.join(' - ');
        };

        if (typeof prop === 'function') {
            var in_name = false;
            for (var i = 0; i < _name.length; i += 1) {
                if (_name[i] === opt.testspec) {
                    in_name = true;
                }
            }
            if (!opt.testspec || in_name) {
                if (opt.moduleStart) {
                    opt.moduleStart();
                }
                exports.runTest(_name, suite[k], opt, cb);
            }
            else {
                return cb();
            }
        }
        else {
            exports.runSuite(_name, suite[k], opt, cb);
        }
    }, callback);
};

/**
 * Run each exported test function or test suite from a loaded module.
 *
 * @param {String} name
 * @param {Object} mod
 * @param {Object} opt
 * @param {Function} callback
 * @api public
 */

exports.runModule = function (name, mod, opt, callback) {
    var options = _copy(types.options(opt));

    var _run = false;
    var _moduleStart = options.moduleStart;

    mod = wrapGroup(mod);

    function run_once() {
        if (!_run) {
            _run = true;
            _moduleStart(name);
        }
    }
    options.moduleStart = run_once;

    var start = new Date().getTime();

    exports.runSuite(null, mod, options, function (err, a_list) {
        var end = new Date().getTime();
        var assertion_list = types.assertionList(a_list, end - start);
        options.moduleDone(name, assertion_list);
        if (nodeunit.complete) {
            nodeunit.complete(name, assertion_list);
        }
        callback(null, a_list);
    });
};

/**
 * Treats an object literal as a list of modules keyed by name. Runs each
 * module and finished with calling 'done'. You can think of this as a browser
 * safe alternative to runFiles in the nodeunit module.
 *
 * @param {Object} modules
 * @param {Object} opt
 * @api public
 */

// TODO: add proper unit tests for this function
exports.runModules = function (modules, opt) {
    var all_assertions = [];
    var options = types.options(opt);
    var start = new Date().getTime();

    async.concatSeries(_keys(modules), function (k, cb) {
        exports.runModule(k, modules[k], options, cb);
    },
    function (err, all_assertions) {
        var end = new Date().getTime();
        options.done(types.assertionList(all_assertions, end - start));
    });
};


/**
 * Wraps a test function with setUp and tearDown functions.
 * Used by testCase.
 *
 * @param {Function} setUp
 * @param {Function} tearDown
 * @param {Function} fn
 * @api private
 */

var wrapTest = function (setUp, tearDown, fn) {
    return function (test) {
        var context = {};
        if (tearDown) {
            var done = test.done;
            test.done = function (err) {
                try {
                    tearDown.call(context, function (err2) {
                        if (err && err2) {
                            test._assertion_list.push(
                                types.assertion({error: err})
                            );
                            return done(err2);
                        }
                        done(err || err2);
                    });
                }
                catch (e) {
                    done(e);
                }
            };
        }
        if (setUp) {
            setUp.call(context, function (err) {
                if (err) {
                    return test.done(err);
                }
                fn.call(context, test);
            });
        }
        else {
            fn.call(context, test);
        }
    };
};


/**
 * Returns a serial callback from two functions.
 *
 * @param {Function} funcFirst
 * @param {Function} funcSecond
 * @api private
 */

var getSerialCallback = function (fns) {
    if (!fns.length) {
        return null;
    }
    return function (callback) {
        var that = this;
        var bound_fns = [];
        for (var i = 0, len = fns.length; i < len; i++) {
            (function (j) {
                bound_fns.push(function () {
                    return fns[j].apply(that, arguments);
                });
            })(i);
        }
        return async.series(bound_fns, callback);
    };
};


/**
 * Wraps a group of tests with setUp and tearDown functions.
 * Used by testCase.
 *
 * @param {Object} group
 * @param {Array} setUps - parent setUp functions
 * @param {Array} tearDowns - parent tearDown functions
 * @api private
 */

var wrapGroup = function (group, setUps, tearDowns) {
    var tests = {};

    var setUps = setUps ? setUps.slice(): [];
    var tearDowns = tearDowns ? tearDowns.slice(): [];

    if (group.setUp) {
        setUps.push(group.setUp);
        delete group.setUp;
    }
    if (group.tearDown) {
        tearDowns.unshift(group.tearDown);
        delete group.tearDown;
    }

    var keys = _keys(group);

    for (var i = 0; i < keys.length; i += 1) {
        var k = keys[i];
        if (typeof group[k] === 'function') {
            tests[k] = wrapTest(
                getSerialCallback(setUps),
                getSerialCallback(tearDowns),
                group[k]
            );
        }
        else if (typeof group[k] === 'object') {
            tests[k] = wrapGroup(group[k], setUps, tearDowns);
        }
    }
    return tests;
};


/**
 * Backwards compatibility for test suites using old testCase API
 */

exports.testCase = function (suite) {
    return suite;
};
