// The page editor: one markdown editor (core.js) inside the edit form, saved
// with the header's SAVE button.
(function () {
    var mount = document.getElementById('editor');
    var hidden = document.getElementById('editor-content');
    if (!mount || !hidden || !window.CM) return;

    var form = hidden.closest('form');
    var editor = MarkdownEditor.create(mount, { doc: hidden.value });

    // --- 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 = editor.getValue();
    }

    // Save POSTs via fetch and then rewrites the *editor's* history entry with
    // the resulting page, so the edit session and its result share a single
    // entry (see history-nav.js). A plain form submit would push a second one
    // and leave the editor sitting in history behind the saved page.
    //
    // The server answers 204 + X-Target instead of a 303 because the target may
    // carry a #section anchor the client cannot compute, and fetch drops the
    // fragment from a followed redirect.
    function postSave() {
        syncContent();
        var body = new URLSearchParams(new FormData(form)).toString();
        fetch(form.action, {
            method: 'POST',
            headers: {
                'Content-Type': 'application/x-www-form-urlencoded',
                'X-Save-Mode': 'replace',
            },
            body: body,
        }).then(function (res) {
            if (!res.ok) {
                return res.text().then(function (msg) {
                    alert(msg || ('Save failed (' + res.status + ')'));
                });
            }
            var target = res.headers.get('X-Target') || form.action;
            // replaceState + reload rather than location.replace: if target
            // differs from the current URL only by fragment the browser would
            // skip the re-fetch and show pre-save content.
            window.history.replaceState(null, '', target);
            window.location.reload();
        }).catch(function () {
            alert('Network error — the page was not saved');
        });
    }

    form.addEventListener('submit', function (e) {
        e.preventDefault();
        postSave();
    });

    // --- Actions ---

    editor.actions.save = function () { form.requestSubmit(); };

    // The toolbar and the header SAVE button both name actions.
    MarkdownEditor.bind(document.body, function () { return editor.actions; });
})();