define(['require',
        'codemirror/lib/codemirror',
        'codemirror/addon/mode/loadmode',
        'base/js/namespace',
        'base/js/events',
        'base/js/utils'],
        function(require, CodeMirror, CodemirrorLoadmode, IPython, events, utils){

            var onload = function(){
                console.log('Kernel haskell kernel.js is loading.');

                // add here logic that shoudl be run once per **page load**
                // like adding specific UI, or changing the default value
                // of codecell highlight.

                // Set tooltips to be triggered after 800ms
                IPython.tooltip.time_before_tooltip = 800;

                // IPython keycodes.
                var space = 32;
                var downArrow = 40;
                IPython.keyboard.keycodes.down = downArrow; // space

                IPython.CodeCell.options_default['cm_config']['mode'] = 'haskell';

                utils.requireCodeMirrorMode('haskell', function(){
                    // Create a multiplexing mode that uses Haskell highlighting by default but
                    // doesn't highlight command-line directives.
                    CodeMirror.defineMode("ihaskell", function(config) {
                        return CodeMirror.multiplexingMode(
                            CodeMirror.getMode(config, "haskell"),
                            {
                                open: /:(?=!)/, // Matches : followed by !, but doesn't consume !
                               close: /^(?!!)/, // Matches start of line not followed by !, doesn't consume character
                               mode: CodeMirror.getMode(config, "text/plain"),
                               delimStyle: "delimit"
                            }
                            );
                    });

                    cells = IPython.notebook.get_cells();
                    for(var i in cells){
                        c = cells[i];
                        if (c.cell_type === 'code') {
                            // Force the mode to be Haskell
                            // This is necessary, otherwise sometimes highlighting just doesn't happen.
                            // This may be an IPython bug.
                            c.code_mirror.setOption('mode', 'ihaskell');
                            c.auto_highlight();
                        }
                    }
                });

                // Prevent the pager from surrounding everything with a <pre>
                IPython.Pager.prototype.append_text = function (text) {
                    this.pager_element.find(".container").append($('<div/>').html(IPython.utils.autoLinkUrls(text)));
                };

                events.on('shell_reply.Kernel', function() {
                    // Add logic here that should be run once per reply.

                    // Highlight things with a .highlight-code class
                    // The id is the mode with with to highlight
                    $('.highlight-code').each(function() {
                        var $this = $(this),
                        $code = $this.html(),
                        $unescaped = $('<div/>').html($code).text();

                    $this.empty();

                    // Never highlight this block again.
                    this.className = "";

                    CodeMirror(this, {
                        value: $unescaped,
                        mode: this.id,
                        lineNumbers: false,
                        readOnly: true
                    });
                    });
                });
                console.log('IHaskell kernel.js should have been loaded.')
            } // end def of onload
            return {onload:onload};
        }
);