(function () {
    var mount = document.getElementById('editor');
    var hidden = document.getElementById('editor-content');
    if (!mount || !hidden || !window.CM) return;

    var form = hidden.closest('form');

    var T = EditorTables;
    var D = EditorDates;
    var M = EditorMovie;

    // --- CodeMirror setup ---

    // Shift+Enter (new table row below) / Shift+Delete (delete table row) run at
    // highest precedence so they win over CM's default newline/forward-delete.
    // Returning false (no table at cursor) lets CM fall back to its default.
    function tableKey(fn) {
        return function (view) {
            var result = fn(view.state.doc.toString(), view.state.selection.main.head);
            if (!result) return false;
            dispatchFullReplace(result);
            return true;
        };
    }

    var tableKeymap = [
        { key: 'Shift-Enter', run: tableKey(T.insertRowBelow) },
        { key: 'Shift-Delete', run: tableKey(T.deleteRow) },
    ];

    var state = CM.EditorState.create({
        doc: hidden.value,
        extensions: [
            CM.history(),
            CM.drawSelection(),
            CM.indentOnInput(),
            CM.EditorView.lineWrapping,
            CM.markdown({ base: CM.markdownLanguage }),
            CM.syntaxHighlighting(CM.highlightStyle),
            CM.closeBrackets(),
            CM.autocompletion({ override: [WikiComplete.source] }),
            CM.theme,
            CM.Prec.highest(CM.keymap.of(tableKeymap)),
            CM.keymap.of([].concat(
                CM.closeBracketsKeymap,
                CM.completionKeymap,
                CM.markdownKeymap,
                CM.defaultKeymap,
                CM.historyKeymap,
                [CM.indentWithTab]
            )),
        ],
    });

    var view = new CM.EditorView({ state: state, parent: mount });
    view.focus();

    // --- CM document helpers ---

    function dispatchFullReplace(result) {
        view.dispatch({
            changes: { from: 0, to: view.state.doc.length, insert: result.text },
            selection: { anchor: result.cursor },
            scrollIntoView: true,
        });
        view.focus();
    }

    function insertAtCursor(s) {
        var sel = view.state.selection.main;
        view.dispatch({
            changes: { from: sel.from, to: sel.to, insert: s },
            selection: { anchor: sel.from + s.length },
            scrollIntoView: true,
        });
        view.focus();
    }

    function wrap(before, after, placeholder) {
        var sel = view.state.selection.main;
        var hadSelection = sel.to > sel.from;
        var selected = hadSelection ? view.state.sliceDoc(sel.from, sel.to) : placeholder;
        var insert = before + selected + after;
        var anchor, head;
        if (hadSelection) {
            anchor = head = sel.from + insert.length;
        } else {
            anchor = sel.from + before.length;
            head = anchor + placeholder.length;
        }
        view.dispatch({
            changes: { from: sel.from, to: sel.to, insert: insert },
            selection: { anchor: anchor, head: head },
            scrollIntoView: true,
        });
        view.focus();
    }

    function linePrefix(prefix) {
        var sel = view.state.selection.main;
        var line = view.state.doc.lineAt(sel.from);
        view.dispatch({
            changes: { from: line.from, to: line.from, insert: prefix },
            selection: { anchor: sel.from + prefix.length },
            scrollIntoView: true,
        });
        view.focus();
    }

    function applyTableOp(fn, arg) {
        var text = view.state.doc.toString();
        var pos = view.state.selection.main.head;
        var result = arg !== undefined ? fn(text, pos, arg) : fn(text, pos);
        if (result) dispatchFullReplace(result);
    }

    // Adapter passed to movie.js so it reads/writes the CM document instead of a
    // textarea (replace() dispatches a transaction; cursor lands after the block).
    var movieCtx = {
        getValue: function () { return view.state.doc.toString(); },
        replace: function (start, end, text) {
            view.dispatch({
                changes: { from: start, to: end, insert: text },
                selection: { anchor: start + text.length },
                scrollIntoView: true,
            });
            view.focus();
        },
    };

    // --- Content sync ---

    // Serialize the CM document into the hidden textarea on submit only — Save
    // must not depend on CM focus or async state (decision 8). requestSubmit
    // fires this listener even for the ALT+SHIFT+S path.
    function syncContent() {
        hidden.value = view.state.doc.toString();
    }
    form.addEventListener('submit', syncContent);

    // --- Actions ---

    var actions = {
        save:           function () { form.requestSubmit(); },
        undo:           function () { CM.undo(view); view.focus(); },
        redo:           function () { CM.redo(view); view.focus(); },
        bold:           function () { wrap('**', '**', 'bold text'); },
        italic:         function () { wrap('*', '*', 'italic text'); },
        h1:             function () { linePrefix('# '); },
        h2:             function () { linePrefix('## '); },
        h3:             function () { linePrefix('### '); },
        code:           function () { wrap('`', '`', 'code'); },
        codeblock:      function () { wrap('```\n', '\n```', 'code'); },
        quote:          function () { linePrefix('> '); },
        link:           function () { wrap('[', '](url)', 'link text'); },
        wikilink:       insertWikilink,
        ul:             function () { linePrefix('- '); },
        ol:             function () { linePrefix('1. '); },
        task:           function () { linePrefix('- [ ] '); },
        hr:             function () { wrap('\n\n---\n\n', '', ''); },
        fmttable:       function () { applyTableOp(T.formatTableText); },
        tblalignleft:   function () { applyTableOp(T.setColumnAlignment, 'left'); },
        tblaligncenter: function () { applyTableOp(T.setColumnAlignment, 'center'); },
        tblalignright:  function () { applyTableOp(T.setColumnAlignment, 'right'); },
        tblinsertcol:   function () { applyTableOp(T.insertColumn); },
        tbldeletecol:   function () { applyTableOp(T.deleteColumn); },
        tblinsertrow:   function () { applyTableOp(T.insertRow); },
        tbldeleterow:   function () { applyTableOp(T.deleteRow); },
        dateiso:        function () { insertAtCursor(D.isoDate()); },
        datelong:       function () { insertAtCursor(D.longDate()); },
        movie:          function () { M.run(movieCtx); },
        wide:           function () {
            var enabled = !document.body.classList.contains('editor-wide');
            document.body.classList.toggle('editor-wide', enabled);
            sessionStorage.setItem('editor-wide', enabled ? '1' : '0');
        },
    };

    // Wiki link button: drop an empty [[]] at the cursor and open the `[[`
    // completion popup so the same autocomplete flow handles target selection.
    function insertWikilink() {
        var sel = view.state.selection.main;
        view.dispatch({
            changes: { from: sel.from, to: sel.to, insert: '[[]]' },
            selection: { anchor: sel.from + 2 },
            scrollIntoView: true,
        });
        view.focus();
        CM.startCompletion(view);
    }

    // --- Keyboard shortcut registration ---

    var keyMap = {};
    document.querySelectorAll('[data-action]').forEach(function (btn) {
        btn.addEventListener('click', function () {
            var action = actions[btn.dataset.action];
            if (action) action();
        });
        if (btn.dataset.key) {
            keyMap[btn.dataset.key] = actions[btn.dataset.action];
        }
    });

    document.addEventListener('keydown', function (e) {
        if (!e.altKey || !e.shiftKey) return;
        // Shift+digit produces a layout-dependent character in e.key (e.g. "!"
        // on US, "!" on DE), so fall back to e.code for digit rows.
        var key = /^Digit[0-9]$/.test(e.code) ? e.code.slice(5) : e.key;
        var action = keyMap[key];
        if (action) {
            e.preventDefault();
            action();
        }
    });

    // --- Dropdowns ---

    // The toolbar scrolls horizontally on mobile, which makes it an overflow
    // container that would clip its absolutely-positioned dropdown menus. Pin an
    // open menu to the viewport under its trigger so it escapes the clip.
    var toolbar = document.querySelector('.editor-toolbar');
    function pinMenu(toggle, menu) {
        if (!menu.classList.contains('is-open')) return;
        var r = toggle.getBoundingClientRect();
        menu.style.position = 'fixed';
        menu.style.top = r.bottom + 'px';
        var left = Math.min(r.left, document.documentElement.clientWidth - menu.offsetWidth - 4);
        menu.style.left = Math.max(4, left) + 'px';
    }

    document.querySelectorAll('.dropdown-toggle').forEach(function (toggle) {
        wireDropdown(toggle);
        var menu = toggle.parentElement.querySelector('.dropdown-menu');
        if (!menu || !toolbar || !toolbar.contains(toggle)) return;
        // Runs after wireDropdown's own click handler has toggled is-open.
        toggle.addEventListener('click', function () { pinMenu(toggle, menu); });
    });
})();