define(['jquery', 'underscore'], function ($, _) {
    
    // IE
    if(typeof(window.console) === 'undefined') {
        window.console = {};
        window.console.log = window.console.error = window.console.info = window.console.debug = window.console.warn = window.console.trace = window.console.dir = window.console.dirxml = window.console.group = window.console.groupEnd = window.console.time = window.console.timeEnd = window.console.assert = window.console.profile = function() {};
    }

    var console = window.console;

    // IE8 & 9
    var methods = ['log', 'debug', 'info','warn','error','assert','dir','clear','profile','profileEnd'];
    if (typeof console.log === 'object' || typeof console.log === 'function') {
        console.debug = console.log;

        _.each(methods, function (method) {
            console['_' + method] = console[method];
        });
    }

    // Can be customized if needed
    console.serverUrl = 'api/log';
    console.levels = ['debug', 'info', 'warn', 'error'];
    // Disabled by default
    console.level = 'off';
    
    var enabledFor = function (level) {
        if(console.level === 'off') return false;
        if (_.indexOf(console.levels, level) === -1) {
            throw new Error('Invalid log level "' + strategy + '", must be one of ' + JSON.stringify(console.levels));
        }
        if (_.indexOf(console.levels, console.level) === -1) {
            throw new Error('Invalid log console.level "' + strategy + '", must be one of ' + JSON.stringify(console.levels));
        }
        return _.indexOf(console.levels, level) >= _.indexOf(console.levels, console.level);
    };

    var log = console._log;
    var debug = console._debug;
    var info = console._info;
    var warn = console._warn;
    var error = console._error;
    
    // console.log = console.debug
    console.log = function () {
        Function.prototype.apply.call(log, this, arguments);
        if(enabledFor('debug')) {
            sendLogToServer('debug', arguments);
        }
    };
    console.debug = function () {
        Function.prototype.apply.call(debug, this, arguments);
        if(enabledFor('debug')) {
            sendLogToServer('debug', arguments);
        }
    };
    console.info = function () {
        Function.prototype.apply.call(info, this, arguments);
        if(enabledFor('info')) {
            sendLogToServer('info', arguments);
        }
    };
    console.warn = function () {
        Function.prototype.apply.call(warn, this, arguments);
        if(enabledFor('warn')) {
            sendLogToServer('warn', arguments);
        }
    };
    console.error = function () {
        Function.prototype.apply.call(error, this, arguments);
        if(enabledFor('error')) {
            sendLogToServer('error', arguments);
        }
    };


    var sendLogToServer = function(level, msg) {
      var message;
        if((typeof msg === 'object') && (msg.length === 1) && (typeof msg[0] === 'string')) {
            message = msg[0];
        }
        else {
            message = JSON.stringify(msg);
        }

        var log = { 'level':level, 'message': message};
        
        $.ajax({
            type: 'POST',
            url: console.serverUrl,
            data: JSON.stringify(log),
            contentType:'application/json',
            success: function(){
                // update log level
            }
        });
    };

    // manage global JS errors
    window.onerror = function(message, url, linenumber) {
        if(enabledFor('error')) {
            sendLogToServer('error', 'JavaScript error: ' + message + ' on line ' + linenumber + ' for ' + url);
        }
    };
});