// ── hyprcrd Plugin API ──
//
// Loaded synchronously BEFORE any module script. Plugins and core both
// register against window.hyprcrd. Plugins MUST NOT import from core
// modules — use this global API instead so they remain decoupled.
//
// Available namespaces:
//   hyprcrd.hooks      — generic event bus (on/emit)
//   hyprcrd.editor     — toolbar command registry
//   hyprcrd.markdown   — fenced block + post-processing registry
//   hyprcrd.util       — DOM helpers exposed for plugin use
//
// Plugins are loaded as <script type="module"> tags after this script
// but before app.js. They self-register on module evaluation; the core
// then queries the registries when needed.

(function () {
    'use strict';

    // ── Generic event bus ───────────────────────────────────────────
    const hookListeners = Object.create(null);
    const hooks = {
        on(name, fn) {
            if (typeof fn !== 'function') return;
            (hookListeners[name] ||= []).push(fn);
        },
        off(name, fn) {
            const arr = hookListeners[name];
            if (!arr) return;
            const idx = arr.indexOf(fn);
            if (idx >= 0) arr.splice(idx, 1);
        },
        emit(name, data) {
            const arr = hookListeners[name];
            if (!arr) return data;
            for (const fn of arr.slice()) {
                try {
                    const r = fn(data);
                    if (r !== undefined) data = r;
                } catch (err) {
                    console.error(`[hyprcrd hook ${name}]`, err);
                }
            }
            return data;
        },
    };

    // ── Editor command registry ─────────────────────────────────────
    // Toolbar buttons with `data-md="<name>"` dispatch to handlers
    // registered here. Plugins inject buttons + register handlers.
    const editorCommands = Object.create(null);
    const editor = {
        registerCommand(name, fn) {
            if (typeof fn !== 'function') return;
            editorCommands[name] = fn;
        },
        unregisterCommand(name) {
            delete editorCommands[name];
        },
        getCommand(name) {
            return editorCommands[name];
        },
        // Set by editor.js after init — gives plugins access to
        // insertMd(before, after, placeholder) and the textarea body
        // without forcing an import dependency.
        api: null,
    };

    // ── Markdown fenced block registry ──────────────────────────────
    // Each entry: { lang: string, handler: (content) => string }
    // The handler receives the raw text inside ```<lang> ... ``` and
    // must return safe HTML (it will pass through DOMPurify after).
    const fencedBlocks = [];
    // Pre/post processors run on the full source text, before/after
    // marked.parse(). Useful for non-fenced syntax extensions.
    const preProcessors = [];
    const postProcessors = [];
    const markdown = {
        registerFencedBlock(lang, handler) {
            if (typeof handler !== 'function') return;
            fencedBlocks.push({ lang, handler });
        },
        getFencedBlocks() {
            return fencedBlocks.slice();
        },
        registerPreProcessor(fn) {
            if (typeof fn === 'function') preProcessors.push(fn);
        },
        getPreProcessors() {
            return preProcessors.slice();
        },
        registerPostProcessor(fn) {
            if (typeof fn === 'function') postProcessors.push(fn);
        },
        getPostProcessors() {
            return postProcessors.slice();
        },
        // Filled in by core markdown.js after load
        render: null,
    };

    // ── Util helpers (mirror of internal util.js) ───────────────────
    let csrfToken = '';
    const util = {
        $(idOrSel) {
            if (typeof idOrSel !== 'string') return null;
            if (idOrSel.startsWith('#') || idOrSel.includes(' ') || idOrSel.includes('.') || idOrSel.includes('[')) {
                return document.querySelector(idOrSel);
            }
            return document.getElementById(idOrSel);
        },
        $$(sel) {
            return Array.from(document.querySelectorAll(sel));
        },
        esc(s) {
            return String(s ?? '').replace(/[&<>"']/g, c => ({
                '&': '&amp;', '<': '&lt;', '>': '&gt;', '"': '&quot;', "'": '&#39;'
            }[c]));
        },
        // CSRF: core calls setCsrf() after auth so plugins can read it.
        // Emits 'csrf.ready' so plugins that need to make state-changing
        // requests on init can defer until auth has happened.
        setCsrf(token) {
            csrfToken = String(token || '');
            if (csrfToken) hooks.emit('csrf.ready', csrfToken);
        },
        csrf() { return csrfToken; },
    };

    /** Generic JSON API call with automatic CSRF header. */
    async function api(path, opts = {}) {
        const headers = { 'Content-Type': 'application/json' };
        if (csrfToken) headers['X-CSRF-Token'] = csrfToken;
        const res = await fetch(path, {
            method: opts.method || 'GET',
            headers,
            body: opts.body !== undefined ? JSON.stringify(opts.body) : undefined,
        });
        return res.json();
    }

    // ── Settings registry ───────────────────────────────────────────
    // Plugins can inject their own tabs into the main settings overlay.
    // The plugin's onShow callback is called whenever the tab becomes visible.
    const settings = {
        registerTab({ id, label, icon, onShow }) {
            if (!id) return;
            const nav = document.getElementById('settings-nav');
            const panelsContainer = document.querySelector('#settings-overlay .overflow-y-auto.p-5');
            if (!nav || !panelsContainer) {
                // DOM not ready — defer to next tick
                requestAnimationFrame(() => settings.registerTab({ id, label, icon, onShow }));
                return;
            }
            if (nav.querySelector(`[data-tab="${id}"]`)) return; // already registered

            // Create tab button
            const btn = document.createElement('button');
            btn.className = 'settings-tab';
            btn.dataset.tab = id;
            const iconClass = icon || 'ph-puzzle-piece';
            btn.innerHTML = `<i class="ph ${iconClass} text-sm"></i><span class="font-pixel text-[10px]">${label || id}</span>`;
            nav.appendChild(btn);

            // Create empty panel container
            let panel = document.getElementById(`settings-panel-${id}`);
            if (!panel) {
                panel = document.createElement('div');
                panel.id = `settings-panel-${id}`;
                panel.className = 'hidden';
                panelsContainer.appendChild(panel);
            }

            // Click handler — duplicates core tab logic (theme.js may also
            // attach its own handler later, but identical work is harmless).
            btn.addEventListener('click', () => {
                nav.querySelectorAll('.settings-tab').forEach(t => t.classList.remove('active'));
                btn.classList.add('active');
                document.querySelectorAll('[id^="settings-panel-"]').forEach(p => p.classList.add('hidden'));
                panel.classList.remove('hidden');
                if (typeof onShow === 'function') {
                    try { onShow(panel); } catch (err) { console.error(`[settings tab ${id}]`, err); }
                }
                hooks.emit('settings.tab.shown', { tab: id, panel });
            });
        },

        /** Open the main settings overlay. */
        open() {
            document.getElementById('settings-btn')?.click();
        },

        /** Open the settings overlay and switch to a specific tab. */
        openTab(id) {
            this.open();
            // Settings opens via click; the tab might need a frame to render
            requestAnimationFrame(() => {
                document.querySelector(`#settings-nav [data-tab="${id}"]`)?.click();
            });
        },
    };

    // ── Dialog API (filled in by core dialog.js after load) ─────────
    // Plugins call hyprcrd.dialog.confirm(...) / hyprcrd.dialog.show(...)
    // instead of native browser confirm()/prompt() so the UI stays themed
    // and consistent.
    const dialog = {
        show: null,    // (opts) => Promise<value|null>   — set by core dialog.js
        /** Convenience confirm wrapper. Returns Promise<true|null>. */
        async confirm(message, opts = {}) {
            if (typeof dialog.show !== 'function') {
                // Core dialog not loaded yet — fall back to native
                return window.confirm(message) ? true : null;
            }
            return dialog.show({
                title: opts.title || 'confirm',
                message,
                input: false,
                danger: opts.danger ?? true,
                okLabel: opts.okLabel || 'Ok',
                cancelLabel: opts.cancelLabel || 'Cancel',
            });
        },
    };

    // ── Plugin metadata registry ────────────────────────────────────
    // Plugins can register themselves here for introspection / debug.
    const plugins = [];
    const registerPlugin = (meta) => {
        if (meta && meta.name) plugins.push(meta);
    };

    window.hyprcrd = {
        hooks,
        editor,
        markdown,
        util,
        api,
        settings,
        dialog,
        plugins,
        registerPlugin,
        version: '1.0',
    };
})();