document.addEventListener('DOMContentLoaded', () => {
    const HF_API = "https://bilalrhch-arabic-tts-api.hf.space";

    // ─────────────────────────────────────────────
    // Voice definitions
    // Add more voices here by uploading <id>.wav + <id>.txt to the HF /voices folder
    // ─────────────────────────────────────────────
    const availableVoices = [
        { id: "Auto",   name: "تلقائي",     nameEn: "Auto",    gender: "ذكاء اصطناعي", color: "#4A90E2" },
        { id: "tariq",  name: "طارق",       nameEn: "Tariq",   gender: "رجل",           color: "#10B981" },
        { id: "omar",   name: "عمر",        nameEn: "Omar",    gender: "رجل",           color: "#F59E0B" },
        { id: "layla",  name: "ليلى",       nameEn: "Layla",   gender: "امرأة",         color: "#E11D48" },
        { id: "nour",   name: "نور",        nameEn: "Nour",    gender: "امرأة",         color: "#8B5CF6" },
    ];

    let selectedVoiceId = "Auto";
    let previewAudio = null;
    let playingVoiceId = null;

    // ─────────────────────────────────────────────
    // Theme Toggle
    // ─────────────────────────────────────────────
    const themeToggle = document.getElementById('theme-toggle');
    const moonIcon    = document.getElementById('moon-icon');
    const sunIcon     = document.getElementById('sun-icon');

    const savedTheme = localStorage.getItem('theme');
    if (savedTheme === 'dark' || (!savedTheme && window.matchMedia('(prefers-color-scheme: dark)').matches)) {
        document.documentElement.setAttribute('data-theme', 'dark');
        moonIcon.classList.add('hidden');
        sunIcon.classList.remove('hidden');
    }

    themeToggle.addEventListener('click', () => {
        const isDark = document.documentElement.getAttribute('data-theme') === 'dark';
        if (isDark) {
            document.documentElement.removeAttribute('data-theme');
            localStorage.setItem('theme', 'light');
            moonIcon.classList.remove('hidden');
            sunIcon.classList.add('hidden');
        } else {
            document.documentElement.setAttribute('data-theme', 'dark');
            localStorage.setItem('theme', 'dark');
            moonIcon.classList.add('hidden');
            sunIcon.classList.remove('hidden');
        }
    });

    // ─────────────────────────────────────────────
    // Voice Selector Modal
    // ─────────────────────────────────────────────
    const voiceBtn      = document.getElementById('custom-voice-btn');
    const voiceModal    = document.getElementById('voice-selector-modal');
    const closeModalBtn = document.getElementById('close-modal-btn');
    const voiceListEl   = document.getElementById('voice-list-container');

    function getInitial(voice) {
        return voice.name.charAt(0);
    }

    function renderVoiceList() {
        voiceListEl.innerHTML = '';
        availableVoices.forEach(voice => {
            const isActive = voice.id === selectedVoiceId;

            const item = document.createElement('div');
            item.className = 'voice-item' + (isActive ? ' active' : '');
            item.dataset.voiceId = voice.id;

            item.innerHTML = `
                <div class="voice-item-left">
                    <div class="avatar" style="background-color: ${voice.color}">${getInitial(voice)}</div>
                    <div class="voice-info">
                        <span class="voice-name">${voice.name}</span>
                        <span class="voice-gender">${voice.gender}</span>
                    </div>
                </div>
                <div class="voice-item-right">
                    ${voice.id !== 'Auto' ? `
                    <button type="button" class="preview-btn" data-voice-id="${voice.id}" title="معاينة الصوت">
                        <div class="preview-audio-anim hidden" id="eq-${voice.id}">
                            <span></span><span></span><span></span>
                        </div>
                        <svg class="play-icon" id="play-icon-${voice.id}" xmlns="http://www.w3.org/2000/svg" width="16" height="16" viewBox="0 0 24 24" fill="currentColor">
                            <path d="M8 5v14l11-7z"/>
                        </svg>
                    </button>` : ''}
                    <svg class="checkmark" xmlns="http://www.w3.org/2000/svg" width="16" height="16" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2.5" stroke-linecap="round" stroke-linejoin="round"><path d="M20 6 9 17l-5-5"/></svg>
                </div>
            `;

            // Select voice on row click (not the preview button)
            item.addEventListener('click', (e) => {
                if (e.target.closest('.preview-btn')) return;
                selectVoice(voice);
                closeModal();
            });

            voiceListEl.appendChild(item);
        });

        // Attach preview button handlers
        voiceListEl.querySelectorAll('.preview-btn').forEach(btn => {
            btn.addEventListener('click', (e) => {
                e.stopPropagation();
                const vId = btn.dataset.voiceId;
                togglePreview(vId);
            });
        });
    }

    function selectVoice(voice) {
        selectedVoiceId = voice.id;

        // Update trigger button display
        document.querySelector('#selected-voice-display .avatar').style.backgroundColor = voice.color;
        document.querySelector('#selected-voice-display .avatar').textContent = getInitial(voice);
        document.querySelector('#selected-voice-display .voice-name').textContent = voice.name;
        document.querySelector('#selected-voice-display .voice-gender').textContent = voice.gender;

        // Re-render to update active checkmark
        renderVoiceList();
    }

    function openModal() {
        renderVoiceList();
        voiceModal.classList.remove('hidden');
        voiceBtn.classList.add('open');
    }

    function closeModal() {
        voiceModal.classList.add('hidden');
        voiceBtn.classList.remove('open');
    }

    voiceBtn.addEventListener('click', () => {
        if (voiceModal.classList.contains('hidden')) {
            openModal();
        } else {
            closeModal();
        }
    });

    closeModalBtn.addEventListener('click', closeModal);

    // Close modal when clicking outside
    document.addEventListener('click', (e) => {
        if (!voiceModal.classList.contains('hidden') &&
            !voiceBtn.contains(e.target) &&
            !voiceModal.contains(e.target)) {
            closeModal();
        }
    });

    // ─────────────────────────────────────────────
    // Audio Preview
    // ─────────────────────────────────────────────
    function togglePreview(voiceId) {
        if (playingVoiceId === voiceId) {
            // Stop the current preview
            stopPreview();
            return;
        }

        // Stop previous if any
        stopPreview();

        const url = `${HF_API}/voices/${voiceId}.wav`;
        previewAudio = new Audio(url);
        playingVoiceId = voiceId;

        // Show EQ animation, hide play icon
        const eq = document.getElementById(`eq-${voiceId}`);
        const playIcon = document.getElementById(`play-icon-${voiceId}`);
        if (eq) eq.classList.remove('hidden');
        if (playIcon) playIcon.classList.add('hidden');

        previewAudio.play().catch(() => {
            // Voice file not uploaded yet — silently fail
            stopPreview();
        });

        previewAudio.addEventListener('ended', stopPreview);
    }

    function stopPreview() {
        if (previewAudio) {
            previewAudio.pause();
            previewAudio.currentTime = 0;
            previewAudio = null;
        }

        if (playingVoiceId) {
            const eq = document.getElementById(`eq-${playingVoiceId}`);
            const playIcon = document.getElementById(`play-icon-${playingVoiceId}`);
            if (eq) eq.classList.add('hidden');
            if (playIcon) playIcon.classList.remove('hidden');
            playingVoiceId = null;
        }
    }

    // ─────────────────────────────────────────────
    // TTS Logic
    // ─────────────────────────────────────────────
    const synthesizeBtn    = document.getElementById('synthesize-btn');
    const btnText          = synthesizeBtn.querySelector('.btn-text');
    const spinner          = synthesizeBtn.querySelector('.spinner');
    const textInput        = document.getElementById('tts-text');
    const speedInput       = document.getElementById('tts-speed');
    const resultContainer  = document.getElementById('result-container');
    const audioPlayer      = document.getElementById('audio-player');
    const downloadBtn      = document.getElementById('download-btn');
    const errorMessage     = document.getElementById('error-message');

    let currentAudioUrl = null;

    synthesizeBtn.addEventListener('click', async () => {
        const text = textInput.value.trim();
        if (!text) {
            showError("الرجاء إدخال النص أولاً");
            return;
        }

        hideError();
        resultContainer.classList.add('hidden');
        setLoading(true);
        stopPreview();
        closeModal();

        try {
            const response = await fetch(`${HF_API}/synthesize`, {
                method: 'POST',
                headers: { 'Content-Type': 'application/json' },
                body: JSON.stringify({
                    text:  text,
                    voice: selectedVoiceId,
                    speed: parseFloat(speedInput.value) || 1.0
                })
            });

            if (!response.ok) {
                const errorData = await response.json().catch(() => null);
                throw new Error(errorData?.detail || `HTTP Error: ${response.status}`);
            }

            const data   = await response.json();
            const taskId = data.task_id;

            document.getElementById('progress-container').classList.remove('hidden');
            pollTaskStatus(taskId);

        } catch (error) {
            console.error("Synthesis error:", error);
            showError(`حدث خطأ أثناء التوليد: ${error.message}`);
            setLoading(false);
        }
    });

    // ─────────────────────────────────────────────
    // Status Polling
    // ─────────────────────────────────────────────
    async function pollTaskStatus(taskId) {
        try {
            const statusRes = await fetch(`${HF_API}/status/${taskId}`);
            if (!statusRes.ok) {
                if (statusRes.status === 404 || statusRes.status === 503) {
                    throw new Error(`تعذر جلب الحالة (HTTP ${statusRes.status}). الخادم قيد إعادة التشغيل، يرجى المحاولة بعد دقيقة.`);
                }
                throw new Error(`Could not fetch status: HTTP ${statusRes.status}`);
            }

            const state = await statusRes.json();

            document.getElementById('progress-fill').style.width = `${state.progress}%`;

            let statusText = `جاري المعالجة... ${state.progress}%`;
            if (state.status === "stitching") statusText = "جاري تجميع الملفات الصوتية...";
            document.getElementById('progress-text').textContent = statusText;

            if (state.status === "completed") {
                document.getElementById('progress-container').classList.add('hidden');
                if (currentAudioUrl && currentAudioUrl.startsWith('blob:')) {
                    URL.revokeObjectURL(currentAudioUrl);
                }
                currentAudioUrl = `${HF_API}/${state.download_url}`;
                audioPlayer.src = currentAudioUrl;
                resultContainer.classList.remove('hidden');
                setLoading(false);
                audioPlayer.play().catch(e => console.log('Autoplay blocked', e));

            } else if (state.status === "failed") {
                throw new Error(state.error || "Unknown background generation error");
            } else {
                setTimeout(() => pollTaskStatus(taskId), 2000);
            }

        } catch (error) {
            console.error("Polling error:", error);
            document.getElementById('progress-container').classList.add('hidden');
            showError(`انقطع الاتصال أو حدث خطأ: ${error.message}`);
            setLoading(false);
        }
    }

    // ─────────────────────────────────────────────
    // Download
    // ─────────────────────────────────────────────
    downloadBtn.addEventListener('click', () => {
        if (!currentAudioUrl) return;
        const a = document.createElement('a');
        a.href = currentAudioUrl;
        a.download = `OmniVoice_Arabic_${new Date().getTime()}.wav`;
        document.body.appendChild(a);
        a.click();
        document.body.removeChild(a);
    });

    // ─────────────────────────────────────────────
    // Utils
    // ─────────────────────────────────────────────
    function setLoading(isLoading) {
        synthesizeBtn.disabled = isLoading;
        if (isLoading) {
            btnText.classList.add('hidden');
            spinner.classList.remove('hidden');
        } else {
            btnText.classList.remove('hidden');
            spinner.classList.add('hidden');
        }
    }

    function showError(msg) {
        errorMessage.textContent = msg;
        errorMessage.classList.remove('hidden');
    }

    function hideError() {
        errorMessage.classList.add('hidden');
    }
});