(function () {
    if (window.DokuWikiProsemirrorFileStatePolyfill) return;

    function mergeAttrsFromHiddenJson(state, input, ownAttrs) {
        if (!input || !state || !state.doc) return null;

        const json = state.doc.toJSON();
        let existingAttrs = {};

        if (input.value) {
            try {
                const existingJson = JSON.parse(input.value);
                if (existingJson && typeof existingJson === 'object' && existingJson.attrs && typeof existingJson.attrs === 'object') {
                    existingAttrs = existingJson.attrs;
                }
            } catch (e) {
                // Ignore invalid JSON and rebuild from the current editor state.
            }
        }

        json.attrs = {
            ...(json.attrs || {}),
            ...existingAttrs,
            ...(ownAttrs || {})
        };

        input.value = JSON.stringify(json);
        return json;
    }

    function makeBurstScheduler(callback) {
        let scheduled = false;

        function runOnce() {
            if (scheduled) return;
            scheduled = true;
            window.requestAnimationFrame(() => {
                scheduled = false;
                callback();
            });
        }

        return function scheduleBurst() {
            runOnce();
            window.setTimeout(runOnce, 0);
            window.setTimeout(runOnce, 100);
            window.setTimeout(runOnce, 300);
        };
    }

    function bindCommonEditorLifecycle(options) {
        const onSwitchToText = options && options.onSwitchToText ? options.onSwitchToText : function () {};
        const onSubmit = options && options.onSubmit ? options.onSubmit : function () {};
        const onEditorToggle = options && options.onEditorToggle ? options.onEditorToggle : function () {};
        const onAfterSwitch = options && options.onAfterSwitch ? options.onAfterSwitch : function () {};

        document.addEventListener('mousedown', (event) => {
            const target = event.target instanceof Element ? event.target : null;
            if (!target || !target.closest('.plugin_prosemirror_useWYSIWYG')) return;
            onSwitchToText();
        }, true);

        document.addEventListener('click', (event) => {
            const target = event.target instanceof Element ? event.target : null;
            if (!target) return;

            if (target.closest('.plugin_prosemirror_useWYSIWYG')) {
                onEditorToggle();
            }

            const submitControl = target.closest('#dw__editform button[type="submit"], #dw__editform input[type="submit"]');
            if (!submitControl) return;
            onSubmit();
        }, true);

        document.addEventListener('submit', (event) => {
            const form = event.target instanceof HTMLFormElement ? event.target : null;
            if (!form || form.id !== 'dw__editform') return;
            onSubmit();
        }, true);

        jQuery(window).on('fastwiki:afterSwitch', function () {
            onAfterSwitch();
        });
    }

    function addPolyfillScript(eventData, pluginBase) {
        if (empty(eventData) || !Array.isArray(eventData.script)) return;
        const src = DOKU_BASE + 'lib/plugins/' + pluginBase + '/script/prosemirror_file_state_polyfill.js';
        eventData.script.push({
            type: 'text/javascript',
            src: src,
            _data: '',
            defer: 'defer'
        });
    }

    function empty(value) {
        return value === null || typeof value === 'undefined';
    }

    window.DokuWikiProsemirrorFileStatePolyfill = {
        addPolyfillScript: addPolyfillScript,
        bindCommonEditorLifecycle: bindCommonEditorLifecycle,
        makeBurstScheduler: makeBurstScheduler,
        mergeAttrsFromHiddenJson: mergeAttrsFromHiddenJson
    };
})();