/**
 * A dialogue type designed to display an appropriate error when a generic
 * javascript error was thrown and caught.
 *
 * @module moodle-core-notification
 * @submodule moodle-core-notification-exception
 */

var EXCEPTION_NAME = 'Moodle exception',
    EXCEPTION;

/**
 * Extends core Dialogue to show the exception dialogue.
 *
 * @param {Object} config Object literal specifying the dialogue configuration properties.
 * @constructor
 * @class M.core.exception
 * @extends M.core.dialogue
 */
EXCEPTION = function(c) {
    var config = Y.mix({}, c);
    config.width = config.width || (M.cfg.developerdebug)?Math.floor(Y.one(document.body).get('winWidth')/3)+'px':null;
    config.closeButton = true;

    // We need to whitelist some properties which are part of the exception
    // prototype, otherwise AttributeCore filters them during value normalisation.
    var whitelist = [
        'message',
        'name',
        'fileName',
        'lineNumber',
        'stack'
    ];
    Y.Array.each(whitelist, function(k) {
        config[k] = c[k];
    });

    EXCEPTION.superclass.constructor.apply(this, [config]);
};
Y.extend(EXCEPTION, M.core.dialogue, {
    _hideTimeout : null,
    _keypress : null,
    initializer : function(config) {
        var content,
            self = this,
            delay = this.get('hideTimeoutDelay');
        this.get(BASE).addClass('moodle-dialogue-exception');
        this.setStdModContent(Y.WidgetStdMod.HEADER,
                '<h1 id="moodle-dialogue-'+config.COUNT+'-header-text">' + Y.Escape.html(config.name) + '</h1>',
                Y.WidgetStdMod.REPLACE);
        content = Y.Node.create('<div class="moodle-exception"></div>')
                .append(Y.Node.create('<div class="moodle-exception-message">'+Y.Escape.html(this.get('message'))+'</div>'))
                .append(Y.Node.create('<div class="moodle-exception-param hidden param-filename"><label>File:</label> ' +
                        Y.Escape.html(this.get('fileName'))+'</div>'))
                .append(Y.Node.create('<div class="moodle-exception-param hidden param-linenumber"><label>Line:</label> ' +
                        Y.Escape.html(this.get('lineNumber'))+'</div>'))
                .append(Y.Node.create('<div class="moodle-exception-param hidden param-stacktrace"><label>Stack trace:</label> <pre>' +
                        this.get('stack')+'</pre></div>'));
        if (M.cfg.developerdebug) {
            content.all('.moodle-exception-param').removeClass('hidden');
        }
        this.setStdModContent(Y.WidgetStdMod.BODY, content, Y.WidgetStdMod.REPLACE);

        if (delay) {
            this._hideTimeout = setTimeout(function(){self.hide();}, delay);
        }
        this.after('visibleChange', this.visibilityChanged, this);
        this.after('destroyedChange', function(){this.get(BASE).remove();}, this);
        this._keypress = Y.on('key', this.hide, window, 'down:13,27', this);
        this.centerDialogue();
    },
    visibilityChanged : function(e) {
        if (e.attrName === 'visible' && e.prevVal && !e.newVal) {
            if (this._keypress) {
                this._keypress.detach();
            }
            var self = this;
            setTimeout(function(){self.destroy();}, 1000);
        }
    }
}, {
    NAME : EXCEPTION_NAME,
    CSS_PREFIX : DIALOGUE_PREFIX,
    ATTRS : {
        /**
         * The message of the alert.
         *
         * @attribute message
         * @type String
         * @default ''
         */
        message : {
            value : ''
        },

        /**
         * The name of the alert.
         *
         * @attribute title
         * @type String
         * @default ''
         */
        name : {
            value : ''
        },

        /**
         * The name of the file where the error was thrown.
         *
         * @attribute fileName
         * @type String
         * @default ''
         */
        fileName : {
            value : ''
        },

        /**
         * The line number where the error was thrown.
         *
         * @attribute lineNumber
         * @type String
         * @default ''
         */
        lineNumber : {
            value : ''
        },

        /**
         * The backtrace from the error
         *
         * @attribute lineNumber
         * @type String
         * @default ''
         */
        stack : {
            setter : function(str) {
                var lines = Y.Escape.html(str).split("\n"),
                    pattern = new RegExp('^(.+)@('+M.cfg.wwwroot+')?(.{0,75}).*:(\\d+)$'),
                    i;
                for (i in lines) {
                    lines[i] = lines[i].replace(pattern,
                            "<div class='stacktrace-line'>ln: $4</div><div class='stacktrace-file'>$3</div><div class='stacktrace-call'>$1</div>");
                }
                return lines.join('');
            },
            value : ''
        },

        /**
         * If set, the dialogue is hidden after the specified timeout period.
         *
         * @attribute hideTimeoutDelay
         * @type Number
         * @default null
         * @optional
         */
        hideTimeoutDelay : {
            validator : Y.Lang.isNumber,
            value : null
        }
    }
});

M.core.exception = EXCEPTION;
