require('dotenv').config();
const { Bot, webhookCallback, InlineKeyboard } = require('grammy');
const db = require('./db');
const { spin } = require('./games/slots');
const { rollDice } = require('./games/dice');

const bot = new Bot(process.env.TELEGRAM_BOT_TOKEN);
const WEBAPP_URL = process.env.WEBAPP_URL || 'https://your-space.hf.space';

// ── Prices in Telegram Stars (XTR) ──────────────────────────────────────────
const CREDIT_PACKAGES = [
    { stars: 10, credits: 100, label: '💫 100 Credits — ⭐ 10 Stars' },
    { stars: 25, credits: 300, label: '💎 300 Credits — ⭐ 25 Stars' },
    { stars: 50, credits: 700, label: '🏆 700 Credits — ⭐ 50 Stars' },
];

// ── Native Telegram Gifts Cache ──────────────────────────────────────────
let cachedGifts = [];
async function refreshGifts() {
    try {
        cachedGifts = await bot.api.getAvailableGifts();
        console.log(`🎁 Loaded ${cachedGifts.length} native Telegram gifts`);
    } catch (e) {
        console.error('❌ Failed to fetch available gifts:', e.message);
    }
}
refreshGifts();
setInterval(refreshGifts, 1000 * 60 * 60); // Refresh hourly

// ── Helpers ──────────────────────────────────────────────────────────────────
function ensureUser(ctx) {
    const u = ctx.from;
    return db.upsertUser(u.id, u.username, u.first_name);
}

function balanceBar(balance) {
    return `💰 Your balance: **${balance} credits**`;
}

// ── /start ───────────────────────────────────────────────────────────────────
bot.command('start', async (ctx) => {
    const user = ensureUser(ctx);
    const keyboard = new InlineKeyboard()
        .webApp('🎮 Open Gift Bot', WEBAPP_URL).row()
        .text('💰 Buy Credits', 'buy_credits').text('🏆 Leaderboard', 'leaderboard').row()
        .text('📊 My Stats', 'my_stats').text('❓ Help', 'help');

    await ctx.reply(
        `🎁 *Welcome to Gift Bot, ${ctx.from.first_name}!*\n\n` +
        `🎰 Spin the slots, 🎲 bet on dice, 🎁 send gifts!\n` +
        `💡 Buy credits with Telegram Stars and play to win!\n\n` +
        `${balanceBar(user.balance)}\n\n` +
        `Use the button below to open the full Mini App 👇`,
        { parse_mode: 'Markdown', reply_markup: keyboard }
    );
});

// ── /balance ────────────────────────────────────────────────────────────────
bot.command('balance', async (ctx) => {
    const user = ensureUser(ctx);
    await ctx.reply(
        `💰 *Your Balance*\n\n` +
        `Credits: **${user.balance}**\n` +
        `Total Won: ${user.total_won} | Lost: ${user.total_lost} | Bets: ${user.total_bets}`,
        { parse_mode: 'Markdown' }
    );
});

// ── /spin [amount] ───────────────────────────────────────────────────────────
bot.command('spin', async (ctx) => {
    const user = ensureUser(ctx);

    if (user.pending_prize_value) {
        return ctx.reply(`🎁 You have a pending gift: **${user.pending_prize_name}**!\n\nUse the buttons below to Claim or Retry.`, {
            parse_mode: 'Markdown',
            reply_markup: new InlineKeyboard().text('✅ Claim', 'claim_prize').text('🔄 Retry', 'retry_prize')
        });
    }

    const parts = ctx.message.text.trim().split(/\s+/);
    const bet = parseInt(parts[1]) || 10;

    if (bet < 5) return ctx.reply('❌ Minimum bet is 5 credits.');
    if (user.balance < bet) return ctx.reply(`❌ Not enough credits! You have ${user.balance} credits.\nUse /buy to top up.`);

    db.deductBalance(user.tg_id, bet, `Slot spin bet`);
    const result = spin(bet, false);

    db.recordBetWin(user.tg_id, result.isWin ? result.payout : 0, bet);

    if (result.isWin) {
        // Find a real gift that matches or pick a random one from cache
        const targetGift = cachedGifts.find(g => g.name === result.prizeName) || cachedGifts[0];
        
        db.setPendingPrize(user.tg_id, result.prizeName, result.payout, targetGift?.id);
        const keyboard = new InlineKeyboard()
            .text('🎁 Claim Native Gift', 'claim_prize')
            .text('🔄 Retry (Risk it!)', 'retry_prize');

        await ctx.reply(
            `🎡 *SPINNING THE WHEEL...*\n\n` +
            `${result.display}\n\n` +
            `🎉 *WON A NATIVE GIFT: ${result.prizeName}!*\n` +
            `This will be sent to your *Telegram Profile*!\n\n` +
            `What would you like to do?`,
            { parse_mode: 'Markdown', reply_markup: keyboard }
        );
    } else {
        const updated = db.getUser(user.tg_id);
        await ctx.reply(
            `🎰 *SPINNING...*\n\n` +
            `${result.display}\n\n` +
            `${result.label}\n` +
            `Bet: ${bet} credits\n\n` +
            `${balanceBar(updated.balance)}`,
            { parse_mode: 'Markdown' }
        );
    }
});

// ── /demo ───────────────────────────────────────────────────────────────────
bot.command('demo', async (ctx) => {
    const result = spin(10, true);
    await ctx.reply(
        `🧪 *DEMO SPIN*\n\n` +
        `${result.display}\n\n` +
        `${result.isWin ? `🎉 (Demo) Won ${result.prizeName}!` : '😢 (Demo) No luck.'}\n\n` +
        `💡 This was a free spin. Try /spin for real!`,
        { parse_mode: 'Markdown' }
    );
});

// ── /bet [amount] [guess 1-6] ────────────────────────────────────────────────
bot.command('bet', async (ctx) => {
    const user = ensureUser(ctx);
    const parts = ctx.message.text.trim().split(/\s+/);
    const bet = parseInt(parts[1]) || 10;
    const guess = parseInt(parts[2]);

    if (!guess || guess < 1 || guess > 6) return ctx.reply('❌ Usage: /bet <amount> <number 1-6>\nExample: /bet 20 3');
    if (bet < 5) return ctx.reply('❌ Minimum bet is 5 credits.');
    if (user.balance < bet) return ctx.reply(`❌ Not enough credits! You have ${user.balance}.\nUse /buy to top up.`);

    db.deductBalance(user.tg_id, bet, `Dice bet`);
    const result = rollDice(bet, guess);
    db.recordBetWin(user.tg_id, result.payout, bet);

    if (result.isWin) {
        db.addBalance(user.tg_id, result.payout, `Dice win x5`);
    }

    const updated = db.getUser(user.tg_id);

    await ctx.reply(
        `🎲 *ROLLING...*\n\n` +
        `You guessed: ${result.guessEmoji}\n` +
        `Result: ${result.resultEmoji}\n\n` +
        `${result.label}\n` +
        `Bet: ${bet} credits${result.isWin ? ` → Won: **${result.payout} credits**` : ''}\n\n` +
        `${balanceBar(updated.balance)}`,
        { parse_mode: 'Markdown' }
    );
});

// /gift command removed as per user request (no credit gifting)

// ── /buy ─────────────────────────────────────────────────────────────────────
bot.command('buy', async (ctx) => {
    ensureUser(ctx);
    const keyboard = new InlineKeyboard();
    CREDIT_PACKAGES.forEach((pkg, i) => {
        keyboard.text(pkg.label, `buy_pkg_${i}`).row();
    });
    await ctx.reply('⭐ *Buy Credits with Telegram Stars*\n\nChoose a package:', {
        parse_mode: 'Markdown',
        reply_markup: keyboard
    });
});

// ── /leaderboard ─────────────────────────────────────────────────────────────
bot.command('leaderboard', async (ctx) => {
    ensureUser(ctx);
    const top = db.getLeaderboard(10);
    const medals = ['🥇', '🥈', '🥉', '4️⃣', '5️⃣', '6️⃣', '7️⃣', '8️⃣', '9️⃣', '🔟'];
    const lines = top.map((u, i) =>
        `${medals[i]} ${u.first_name || u.username || 'User'} — **${u.balance} credits**`
    ).join('\n');
    await ctx.reply(`🏆 *Leaderboard*\n\n${lines || 'No users yet!'}`, { parse_mode: 'Markdown' });
});

// ── /help ─────────────────────────────────────────────────────────────────────
bot.command('help', async (ctx) => {
    ensureUser(ctx);
    await ctx.reply(
        `*🎁 Gift Bot Commands*\n\n` +
        `/start — Welcome screen\n` +
        `/balance — Check your credits\n` +
        `/spin [amount] — Spin for real Telegram Gifts\n` +
        `/bet [amount] [1-6] — Dice betting\n` +
        `/buy — Top up credits with Stars\n` +
        `/leaderboard — Top winners\n\n` +
        `💡 *Prizes:* Real native Telegram profile gifts!`,
        { parse_mode: 'Markdown' }
    );
});

// ── Inline Button Callbacks ──────────────────────────────────────────────────
bot.callbackQuery('claim_prize', async (ctx) => {
    const user = ensureUser(ctx);
    const prize = db.claimPrize(user.tg_id);
    if (!prize) return ctx.answerCallbackQuery('❌ No prize to claim');

    await ctx.answerCallbackQuery(`🎁 Sending native gift...`);
    
    try {
        if (prize.gift_id) {
            // NATIVE TELEGRAM GIFT SENDING
            await ctx.api.sendGift(user.tg_id, prize.gift_id, "Congratulations from GiftBot! 🎆");
            db.logSentGift(user.tg_id, prize.gift_id, prize.name);
            
            await ctx.editMessageText(
                `🎆 *SUCCESS! GIFT SENT!*\n\n` +
                `A real **${prize.name}** has been sent to your Telegram Profile!\n` +
                `Check your *Gifts* section in your profile.\n\n` +
                balanceBar(db.getUser(user.tg_id).balance),
                { parse_mode: 'Markdown' }
            );
        } else {
            // Fallback to credits if no gift_id (old record)
            await ctx.editMessageText(
                `✅ *Credits Claimed!*\n\n` +
                `You received **${prize.val} credits**.\n\n` +
                balanceBar(db.getUser(user.tg_id).balance),
                { parse_mode: 'Markdown' }
            );
        }
    } catch (e) {
        console.error('sendGift Error:', e);
        // If error (e.g. PAYMENT_REQUIRED), return credits as fallback so user isn't stuck
        db.addBalance(user.tg_id, prize.val || 100, "Refund: Gift sending failed");
        await ctx.reply(`❌ *Gift Delivery Failed*\n\nError: ${e.message}\n\n> 💡 Note: Bot needs a Star balance and Business subscription.\nWe've credited **100 credits** to your balance as compensation.`, {
            parse_mode: 'Markdown'
        });
    }
});

bot.callbackQuery('retry_prize', async (ctx) => {
    const user = ensureUser(ctx);
    if (!user.pending_prize_value) return ctx.answerCallbackQuery('❌ No prize to retry');

    const oldPrizeName = user.pending_prize_name;
    const originalBet = user.pending_prize_value / 10;
    db.clearPendingPrize(user.tg_id);

    await ctx.answerCallbackQuery('🔄 Retrying spin...');
    await ctx.editMessageText(`🎰 *RE-SPINNING...*`);

    const result = spin(originalBet, false);
    if (result.isWin) {
        db.setPendingPrize(user.tg_id, result.prizeName, result.payout);
        const keyboard = new InlineKeyboard()
            .text('✅ Claim Credits', 'claim_prize')
            .text('🔄 Retry (Risk it!)', 'retry_prize');

        await ctx.editMessageText(
            `🎰 *RE-SPIN RESULT*\n\n` +
            `${result.display}\n\n` +
            `🎉 *WON ${result.prizeName}!*\n` +
            `Value: **${result.payout} credits**\n\n` +
            `Claim or Retry?`,
            { parse_mode: 'Markdown', reply_markup: keyboard }
        );
    } else {
        const updated = db.getUser(user.tg_id);
        await ctx.editMessageText(
            `🎰 *RE-SPIN RESULT*\n\n` +
            `${result.display}\n\n` +
            `❌ Lost the retry!\n` +
            `The ${oldPrizeName} is gone.\n\n` +
            balanceBar(updated.balance),
            { parse_mode: 'Markdown' }
        );
    }
});

bot.callbackQuery('buy_credits', async (ctx) => {
    await ctx.answerCallbackQuery();
    const keyboard = new InlineKeyboard();
    CREDIT_PACKAGES.forEach((pkg, i) => keyboard.text(pkg.label, `buy_pkg_${i}`).row());
    await ctx.reply('⭐ *Choose a Credit Package:*', { parse_mode: 'Markdown', reply_markup: keyboard });
});

bot.callbackQuery('leaderboard', async (ctx) => {
    await ctx.answerCallbackQuery();
    const top = db.getLeaderboard(10);
    const medals = ['🥇', '🥈', '🥉', '4️⃣', '5️⃣', '6️⃣', '7️⃣', '8️⃣', '9️⃣', '🔟'];
    const lines = top.map((u, i) =>
        `${medals[i]} ${u.first_name || u.username || 'User'} — **${u.balance}**`
    ).join('\n');
    await ctx.reply(`🏆 *Leaderboard*\n\n${lines || 'No players yet!'}`, { parse_mode: 'Markdown' });
});

bot.callbackQuery('my_stats', async (ctx) => {
    await ctx.answerCallbackQuery();
    const user = ensureUser(ctx);
    await ctx.reply(
        `📊 *Your Stats*\n\n` +
        `💰 Balance: ${user.balance} credits\n` +
        `🏆 Total Won: ${user.total_won}\n` +
        `💸 Total Lost: ${user.total_lost}\n` +
        `🎲 Total Bets: ${user.total_bets}`,
        { parse_mode: 'Markdown' }
    );
});

bot.callbackQuery('help', async (ctx) => {
    await ctx.answerCallbackQuery();
    await ctx.reply(
        `*🎁 Gift Bot Commands*\n\n/start /balance /spin /bet /gift /buy /leaderboard /help`,
        { parse_mode: 'Markdown' }
    );
});

// ── Buy Package — send Stars invoice ─────────────────────────────────────────
for (let i = 0; i < CREDIT_PACKAGES.length; i++) {
    bot.callbackQuery(`buy_pkg_${i}`, async (ctx) => {
        await ctx.answerCallbackQuery();
        const pkg = CREDIT_PACKAGES[i];
        await ctx.replyWithInvoice(
            `Buy ${pkg.credits} Credits`,
            `Top up your Gift Bot wallet with ${pkg.credits} credits and start playing!`,
            `credits_${i}`, // payload
            'XTR',          // Telegram Stars currency
            [{ label: `${pkg.credits} Credits`, amount: pkg.stars }]
        );
    });
}

// ── Pre-checkout: always approve ─────────────────────────────────────────────
bot.on('pre_checkout_query', async (ctx) => {
    await ctx.answerPreCheckoutQuery(true);
});

// ── Successful payment: credit user ──────────────────────────────────────────
bot.on('message:successful_payment', async (ctx) => {
    const payload = ctx.message.successful_payment.invoice_payload;
    const stars = ctx.message.successful_payment.total_amount;
    const user = ensureUser(ctx);

    const pkgIndex = parseInt(payload.replace('credits_', ''));
    const pkg = CREDIT_PACKAGES[pkgIndex];

    if (pkg) {
        db.addBalance(user.tg_id, pkg.credits, `Bought ${pkg.credits} credits for ${stars} Stars`);
        const updated = db.getUser(user.tg_id);
        await ctx.reply(
            `✅ *Payment Successful!*\n\n` +
            `You received **${pkg.credits} credits**!\n\n` +
            `${balanceBar(updated.balance)}`,
            { parse_mode: 'Markdown' }
        );
    }
});

module.exports = bot;