document.addEventListener('DOMContentLoaded', () => {
    // Initialize Lucide Icons
    lucide.createIcons();

    // Elements
    const themeToggle = document.getElementById('themeToggle');
    const startScrape = document.getElementById('startScrape');
    const userInput = document.getElementById('userInput');
    const landingHero = document.getElementById('landingHero');
    const loadingState = document.getElementById('loadingState');
    const resultsSection = document.getElementById('resultsSection');
    const statusText = document.getElementById('statusText');
    const progressBar = document.getElementById('progressBar');
    
    // Config Elements
    const reviewCountType = document.getElementById('reviewCountType');
    const sortOrder = document.getElementById('sortOrder');
    const starRating = document.getElementById('starRating');

    // Theme Logic
    themeToggle.addEventListener('click', () => {
        const html = document.documentElement;
        if (html.classList.contains('dark')) {
            html.classList.remove('dark');
            localStorage.setItem('theme', 'light');
        } else {
            html.classList.add('dark');
            localStorage.setItem('theme', 'dark');
        }
    });

    // Load Saved Theme
    if (localStorage.getItem('theme') === 'dark' || (!('theme' in localStorage) && window.matchMedia('(prefers-color-scheme: dark)').matches)) {
        document.documentElement.classList.add('dark');
    }

    // Scrape Logic
    startScrape.addEventListener('click', async () => {
        const identifier = userInput.value.trim();
        if (!identifier) {
            alert('Please enter an app name or URL');
            return;
        }

        // 1. Transition to Loading
        landingHero.classList.add('hidden');
        loadingState.classList.remove('hidden');
        
        // 2. Mock Progress Simulation
        let progress = 0;
        const progressInterval = setInterval(() => {
            if (progress < 90) {
                progress += Math.random() * 5;
                progressBar.style.width = `${progress}%`;
                
                if (progress < 30) statusText.innerText = 'Connecting to Google Play...';
                else if (progress < 60) statusText.innerText = 'Bypassing Protection...';
                else statusText.innerText = 'Parsing Reviews...';
            }
        }, 500);

        // 3. Actual API Call
        try {
            const countValue = reviewCountType.value === 'fixed_500' ? 500 : (reviewCountType.value === 'all' ? 'all' : 150);
            
            const response = await fetch('/scrape', {
                method: 'POST',
                headers: { 'Content-Type': 'application/json' },
                body: JSON.stringify({
                    identifier,
                    review_count_type: reviewCountType.value === 'all' ? 'all' : 'fixed',
                    review_count: countValue,
                    sort_order: sortOrder.value,
                    star_rating: starRating.value
                })
            });

            const data = await response.json();

            if (!response.ok) {
                throw new Error(data.error || 'Failed to fetch reviews');
            }

            // 4. Success - Render Results
            clearInterval(progressInterval);
            progressBar.style.width = '100%';
            statusText.innerText = 'Done!';
            
            setTimeout(() => {
                renderResults(data);
                loadingState.classList.add('hidden');
                resultsSection.classList.remove('hidden');
            }, 600);

        } catch (err) {
            clearInterval(progressInterval);
            alert(err.message);
            loadingState.classList.add('hidden');
            landingHero.classList.remove('hidden');
            progressBar.style.width = '0%';
        }
    });

    function renderResults(data) {
        const { app_info, reviews } = data;
        
        // Update Header
        document.getElementById('appIcon').src = app_info.icon;
        document.getElementById('appTitle').innerText = app_info.title;
        document.getElementById('appScore').innerText = app_info.score.toFixed(1);
        document.getElementById('appReviewCount').innerText = formatNumber(app_info.reviews);
        document.getElementById('appDesc').innerText = app_info.summary;
        document.getElementById('reviewStats').innerText = `Showing ${reviews.length} results`;

        // Stars
        const stars = Math.round(app_info.score);
        const starContainer = document.getElementById('starContainer');
        starContainer.innerHTML = '';
        for (let i = 0; i < 5; i++) {
            const starIcon = document.createElement('i');
            starIcon.setAttribute('data-lucide', 'star');
            starIcon.classList.add('w-5', 'h-5');
            if (i < stars) starIcon.classList.add('fill-current');
            starContainer.appendChild(starIcon);
        }

        // Review Feed
        const feed = document.getElementById('reviewFeed');
        feed.innerHTML = '';
        
        reviews.forEach(review => {
            const card = document.createElement('div');
            card.className = 'bg-white dark:bg-slate-900 p-6 rounded-2xl border border-slate-200 dark:border-slate-800 space-y-3 transition-hover hover:border-primary/30';
            
            card.innerHTML = `
                <div class="flex justify-between items-start">
                    <div class="flex items-center gap-3">
                        <img src="${review.userImage || 'https://www.gravatar.com/avatar/00000000000000000000000000000000?d=mp&f=y'}" 
                             class="w-10 h-10 rounded-full border border-slate-200 dark:border-slate-700">
                        <div>
                            <div class="font-bold text-sm">${review.userName}</div>
                            <div class="text-xs text-slate-400">${new Date(review.at).toLocaleDateString()}</div>
                        </div>
                    </div>
                    <div class="flex text-yellow-500">
                        ${Array(review.score).fill('<i data-lucide="star" class="w-3 h-3 fill-current"></i>').join('')}
                    </div>
                </div>
                <p class="text-slate-600 dark:text-slate-400 text-sm leading-relaxed">${review.content}</p>
                <div class="flex items-center gap-4 text-xs font-bold text-slate-400">
                    <span class="flex items-center gap-1"><i data-lucide="thumbs-up" class="w-3 h-3"></i> ${review.thumbsUpCount}</span>
                </div>
            `;
            feed.appendChild(card);
        });

        lucide.createIcons();

        // Download Action
        document.getElementById('downloadCSV').onclick = () => {
            downloadCSV(data.reviews, `${app_info.appId}_reviews.csv`);
        };
    }

    function downloadCSV(arr, filename) {
        const headers = Object.keys(arr[0]).join(',');
        const rows = arr.map(obj => Object.values(obj).map(val => `"${val}"`).join(',')).join('\\n');
        const csvContent = "data:text/csv;charset=utf-8," + headers + '\\n' + rows;
        const encodedUri = encodeURI(csvContent);
        const link = document.createElement("a");
        link.setAttribute("href", encodedUri);
        link.setAttribute("download", filename);
        document.body.appendChild(link);
        link.click();
        document.body.removeChild(link);
    }

    function formatNumber(num) {
        if (num >= 1000000) return (num / 1000000).toFixed(1) + 'M';
        if (num >= 1000) return (num / 1000).toFixed(1) + 'K';
        return num;
    }
});