const { Scenes, Markup } = require('telegraf');
const Order = require('../../models/Order');
const Product = require('../../models/Product');
const User = require('../../models/User');
const config = require('../../config');
const userController = require('../../controllers/userController');

const formatPrice = (price) => {
    return price.toString().replace(/\B(?=(\d{3})+(?!\d))/g, " ");
};

// Common Keyboard
const navKeyboard = (ctx, i18n, extras = []) => {
    const back = i18n.btn_back_nav || "⬅️ Back";
    const cancel = i18n.btn_cancel || "❌ Cancel";
    const k = [[back, cancel]];
    if (extras.length) k.unshift(...extras);
    return Markup.keyboard(k).resize().oneTime();
};

const checkNav = (ctx) => {
    if (!ctx.message || !ctx.message.text) return null;
    const text = ctx.message.text;
    const i18n = ctx.i18n || require('../../locales').uz;

    const btnCancel = i18n.btn_cancel || "❌ Cancel";
    const btnBack = i18n.btn_back_nav || "⬅️ Back";

    // Robust checking against localised strings
    if (text === btnCancel || text === '❌ Bekor qilish' || text === '❌ Отмена' || text === '❌ Cancel') {
        ctx.scene.leave();
        ctx.reply(i18n.cancel_process || "Cancelled", Markup.removeKeyboard());
        return 'STOP';
    }
    if (text === btnBack || text === '⬅️ Ortga' || text === '⬅️ Назад' || text === '⬅️ Back') {
        return 'BACK';
    }
    return null;
};

async function finishOrder(ctx) {
    try {
        const state = ctx.wizard.state;
        const cart = ctx.session.cart || [];
        const i18n = ctx.i18n || require('../../locales').uz;

        for (const item of cart) {
            await Product.updateOne({ id: item.id }, { $inc: { quantity: -item.count } });
        }

        // Save Address if New and Delivery (Yandex)
        if (state.deliveryMethod === i18n.delivery_yandex && state.isNewAddress && state.location) {
            await User.updateOne(
                { id: ctx.from.id },
                { $push: { addresses: { name: `Manzil ${new Date().toLocaleDateString()}`, latitude: state.location.latitude, longitude: state.location.longitude } } }
            );
        }

        const orderData = {
            id: Date.now(),
            userId: ctx.from.id,
            user: state.fullName || ctx.from.first_name,
            phone: state.phone,
            deliveryMethod: state.deliveryMethod,
            location: state.location,
            addressText: state.addressText,
            deliveryTime: state.deliveryTime || 'Standard',
            comment: state.comment,
            items: cart,
            total: state.total,
            paymentMethod: state.paymentMethod,
            status: 'new'
        };

        const newOrder = new Order(orderData);
        await newOrder.save();

        // Update User Phone if new
        await User.updateOne({ id: ctx.from.id }, { phone: state.phone });

        ctx.reply(`${i18n.confirm_order}\n#${newOrder.id}\n${i18n.order_details_pay} ${state.paymentMethod}`, Markup.removeKeyboard());

        // Notify Admins
        let locInfo = "";
        if (state.deliveryMethod === i18n.delivery_bts) {
            locInfo = `📝 <b>BTS:</b>\n${state.addressText}\n👤 <b>F.I.O:</b> ${state.fullName}`;
        } else if (state.location) {
            locInfo = `📍 <a href="https://www.google.com/maps?q=${state.location.latitude},${state.location.longitude}">Lokatsiya</a>`;
        } else {
            locInfo = "🏃 Olib ketish";
        }

        const adminText = `🆕 <b>Yangi buyurtma!</b>\n#${newOrder.id}\n👤: ${newOrder.user}\n📞: ${newOrder.phone}\n🚚: ${state.deliveryMethod}\n${locInfo}\n🕒: ${state.deliveryTime || '-'}\n💬: ${state.comment || "Yo'q"}\n💰: ${state.paymentMethod}\n\n` +
            cart.map(item => `- ${item.name} (${item.count}x)`).join('\n') +
            `\n\nJami: ${formatPrice(newOrder.total)} ${i18n.currency}`;

        const btns = Markup.inlineKeyboard([Markup.button.callback("👁 Ko'rish", `admin_order_${newOrder.id}`)]);

        for (const adminId of config.ADMIN_IDS) {
            try {
                await ctx.telegram.sendMessage(adminId, adminText, { parse_mode: 'HTML', ...btns });
                if (state.location) await ctx.telegram.sendLocation(adminId, state.location.latitude, state.location.longitude);
                if (state.paymentProof) await ctx.telegram.sendPhoto(adminId, state.paymentProof, { caption: `🧾 Chek (#${newOrder.id})` });
            } catch (e) { console.error(e); }
        }

        ctx.session.cart = [];
        return ctx.scene.leave();

    } catch (err) {
        console.error("ORDER_CREATION_ERROR:", err);

        // Handle Duplicate Key Error (Self-Healing Attempt)
        if (err.code === 11000) {
            ctx.reply("⚠️ Tizimda qisqa nosozlik (ID Duplicate). Iltimos, qayta 'Buyurtma berish' tugmasini bosing.");
            // Ideally we retry, but for now asking user is safer than infinite loop
        } else {
            const errorMsg = (err.message || "").substring(0, 50);
            ctx.reply(`❌ Tizim xatoligi yuz berdi: ${errorMsg}\n\nIltimos, adminga xabar bering.`);
            // Notify admin about the crash
            for (const adminId of config.ADMIN_IDS) {
                ctx.telegram.sendMessage(adminId, `🚨 **CRITICAL CHECKOUT ERROR**:\nUser: ${ctx.from.id}\nError: ${err.message}`, { parse_mode: 'Markdown' }).catch(e => console.error(e));
            }
        }
        return ctx.scene.leave();
    }
}

const checkoutScene = new Scenes.WizardScene(
    'CHECKOUT_SCENE',
    // Step 0: Pre-flight Check & Phone
    async (ctx) => {
        const i18n = ctx.i18n || require('../../locales').uz;
        const cart = ctx.session.cart || [];
        ctx.wizard.state.i18n = i18n; // Save specifically for wizard reuse

        // 1. Stock Validation
        const conflicts = [];
        for (const item of cart) {
            const product = await Product.findOne({ id: item.id });
            if (!product || product.quantity < item.count) {
                conflicts.push(`${item.name} (${product ? product.quantity : 0})`);
            }
        }

        if (conflicts.length > 0) {
            ctx.reply(`⚠️ ${i18n.cart_stock_err.replace('{item}', conflicts.join(', ')).replace('{stock}', '...')} \n\nIltimos savatni yangilang.`);
            ctx.scene.leave();
            return; // Stop checkout
        }

        // 2. Phone Input
        const user = await User.findOne({ id: ctx.from.id });
        ctx.wizard.state.user = user;

        // NUCLEAR DEFENSIVE FIX
        const btnPhone = (i18n && i18n.phone_button) ? i18n.phone_button : "📱 Raqamni yuborish";
        const btnCancel = (i18n && i18n.btn_cancel) ? i18n.btn_cancel : "❌ Bekor qilish";
        const msgText = (i18n && i18n.phone_prompt) ? i18n.phone_prompt : "Telefon raqamingizni yuboring:";

        console.log("CHECKOUT_DEBUG: Initializing Step 0 with safe keys:", { btnPhone, btnCancel });

        let keyboardRows = [];

        // Add Saved Phone if exists
        if (user && user.phone) {
            const savedTemplate = (i18n && i18n.checkout_phone_saved) ? i18n.checkout_phone_saved : "📱 Mening raqamim: {phone}";
            const savedBtnText = savedTemplate.replace('{phone}', user.phone || "");
            if (savedBtnText) keyboardRows.push([Markup.button.text(savedBtnText)]);
        }

        // Add Contact Request Button
        if (btnPhone) keyboardRows.push([Markup.button.contactRequest(btnPhone)]);

        // Add Cancel Button
        if (btnCancel) keyboardRows.push([Markup.button.text(btnCancel)]);

        // Filter any potentially empty rows just in case
        keyboardRows = keyboardRows.filter(row => row && row.length > 0 && row[0]);

        try {
            ctx.reply(msgText, Markup.keyboard(keyboardRows).resize().oneTime());
        } catch (e) {
            console.error("CHECKOUT_DEBUG_CRASH:", e);
            ctx.reply("Checkout Error (Keyboard). Type /start");
        }
        return ctx.wizard.next();
    },
    // Step 1: Handle Phone -> Delivery
    (ctx) => {
        const i18n = ctx.wizard.state.i18n || ctx.i18n;
        const nav = checkNav(ctx);
        if (nav === 'STOP') return;

        let phone = '';
        if (ctx.message.contact) {
            phone = ctx.message.contact.phone_number;
        } else if (ctx.message.text) {
            // Check if user clicked "My Saved Phone"
            const savedText = i18n.checkout_phone_saved.replace('{phone}', '');
            if (ctx.message.text.includes(savedText.trim()) && ctx.wizard.state.user && ctx.wizard.state.user.phone) {
                phone = ctx.wizard.state.user.phone;
            } else {
                if (!/^\+?[0-9]{9,15}$/.test(ctx.message.text.replace(/\s/g, ''))) {
                    ctx.reply(i18n.error_phone, navKeyboard(ctx, i18n));
                    return;
                }
                phone = ctx.message.text;
            }
        } else {
            ctx.reply(i18n.phone_prompt, navKeyboard(ctx, i18n)); return;
        }

        ctx.wizard.state.phone = phone;

        ctx.reply(i18n.delivery_select, Markup.keyboard([
            [i18n.delivery_yandex, i18n.delivery_bts],
            [i18n.delivery_pickup],
            [i18n.btn_back_nav, i18n.btn_cancel]
        ]).resize().oneTime());
        return ctx.wizard.next();
    },
    // Step 2: Handle Delivery Selection
    async (ctx) => {
        const i18n = ctx.wizard.state.i18n || ctx.i18n;
        const nav = checkNav(ctx);
        if (nav === 'STOP') return;
        if (nav === 'BACK') {
            ctx.wizard.selectStep(0);
            return await ctx.wizard.steps[0](ctx);
        }

        const text = ctx.message.text.trim(); // Trim input
        ctx.wizard.state.deliveryMethod = text;

        if (text.includes('BTS') || text.includes('Почта')) {
            ctx.wizard.state.deliveryMethod = i18n.delivery_bts;
            ctx.reply("📝 " + i18n.settings_addr, navKeyboard(ctx, i18n));
            return ctx.wizard.next(); // Step 3
        }

        if (text.includes('Yandex') || text.includes('Taxi') || text.includes('Такси')) {
            ctx.wizard.state.deliveryMethod = i18n.delivery_yandex;
            // Yandex Explicit Check
            const user = ctx.wizard.state.user;
            const btns = [];
            if (user && user.addresses && user.addresses.length > 0) {
                user.addresses.forEach((addr, i) => {
                    btns.push([i18n.checkout_location_saved.replace('{name}', addr.name || 'Saved Address')]);
                });
            }
            btns.push([Markup.button.locationRequest(i18n.location_button)]);
            btns.push([i18n.btn_back_nav, i18n.btn_cancel]);

            ctx.reply(i18n.address_prompt, Markup.keyboard(btns).resize().oneTime());
            return ctx.wizard.selectStep(5); // Step 5
        }

        // Pickup Check (Robust)
        if (text.includes('Olib ketish') || text.includes('Самовывоз') || text.includes('Pickup')) {
            ctx.wizard.state.deliveryMethod = i18n.delivery_pickup;
            ctx.wizard.state.location = null;

            const Settings = require('../../models/Settings');
            const storeSettings = await Settings.findOne({ key: 'store_location' }); // Optimized query placement

            if (storeSettings && storeSettings.value) {
                const { text, latitude, longitude } = storeSettings.value;
                await ctx.reply(`📍 **Bizning manzil:**\n${text}`, { parse_mode: 'Markdown' });
                await ctx.replyWithLocation(latitude, longitude);
            } else {
                await ctx.reply("📍 **Bizning manzil:**\nToshkent sh... (Default)");
            }

            ctx.reply("🕒 Iltimos, vaqtni yozing (Masalan: 14:30):", Markup.keyboard([
                ["📅 Bugun", "📅 Ertaga"],
                [i18n.btn_back_nav, i18n.btn_cancel]
            ]).resize().oneTime());
            return ctx.wizard.selectStep(6);
        }

        // Unknown Input
        ctx.reply(i18n.delivery_select, Markup.keyboard([
            [i18n.delivery_yandex, i18n.delivery_bts],
            [i18n.delivery_pickup],
            [i18n.btn_back_nav, i18n.btn_cancel]
        ]).resize().oneTime());
        return; // Stay in step
    },
    // Step 3: BTS Address
    (ctx) => {
        const i18n = ctx.wizard.state.i18n || ctx.i18n;
        const nav = checkNav(ctx);
        if (nav === 'STOP') return;
        if (nav === 'BACK') {
            ctx.reply(i18n.delivery_select, Markup.keyboard([
                [i18n.delivery_yandex, i18n.delivery_bts],
                [i18n.delivery_pickup],
                [i18n.btn_back_nav, i18n.btn_cancel]
            ]).resize().oneTime());
            return ctx.wizard.selectStep(2);
        }

        ctx.wizard.state.addressText = ctx.message.text;
        ctx.reply("👤 F.I.O (To'liq):", navKeyboard(ctx, i18n));
        return ctx.wizard.next();
    },
    // Step 4: BTS Name
    (ctx) => {
        const i18n = ctx.wizard.state.i18n || ctx.i18n;
        const nav = checkNav(ctx);
        if (nav === 'STOP') return;
        if (nav === 'BACK') return ctx.wizard.selectStep(3);

        ctx.wizard.state.fullName = ctx.message.text;
        ctx.wizard.state.paymentMethod = i18n.payment_card; // BTS is usually Card only logic from previous Code

        ctx.reply("📝 Izoh (Comment)?", Markup.keyboard([
            ["Yo'q"],
            [i18n.btn_back_nav, i18n.btn_cancel]
        ]).resize());
        return ctx.wizard.selectStep(7);
    },
    // Step 5: Yandex Address
    async (ctx) => {
        const i18n = ctx.wizard.state.i18n || ctx.i18n;
        const nav = checkNav(ctx);
        if (nav === 'STOP') return;
        if (nav === 'BACK') {
            ctx.reply(i18n.delivery_select, Markup.keyboard([
                [i18n.delivery_yandex, i18n.delivery_bts],
                [i18n.delivery_pickup],
                [i18n.btn_back_nav, i18n.btn_cancel]
            ]).resize().oneTime());
            return ctx.wizard.selectStep(2);
        }

        let location = null;
        if (ctx.message.location) {
            location = ctx.message.location;
            ctx.wizard.state.isNewAddress = true;
        } else if (ctx.message.text) {
            // Find in saved
            const user = ctx.wizard.state.user;
            if (user && user.addresses) {
                // Fuzzy match or exact match depending on format
                // We formatted buttons as: i18n.checkout_location_saved.replace('{name}', addr.name)
                // Let's try to match by name
                const savedFormat = i18n.checkout_location_saved.replace('{name}', '');
                const name = ctx.message.text.replace(savedFormat, '').trim();
                // This might be tricky if "Saved: " is empty.
                // Simple loop match
                const found = user.addresses.find(a => ctx.message.text.includes(a.name));
                if (found) location = { latitude: found.latitude, longitude: found.longitude };
            }
        }

        if (!location) {
            ctx.reply("⚠️ " + i18n.settings_loc, navKeyboard(ctx, i18n));
            return;
        }
        ctx.wizard.state.location = location;

        ctx.reply("🕒 Iltimos, vaqtni yozing (Masalan: 15:00):", Markup.keyboard([
            ["📅 Bugun", "📅 Ertaga"],
            [i18n.btn_back_nav, i18n.btn_cancel]
        ]).resize().oneTime());
        return ctx.wizard.next(); // To Step 6
    },
    // Step 6: Time
    (ctx) => {
        const i18n = ctx.wizard.state.i18n || ctx.i18n;
        const nav = checkNav(ctx);
        if (nav === 'STOP') return;
        if (nav === 'BACK') {
            // Logic to go back to Address
            return ctx.wizard.selectStep(5);
        }

        ctx.wizard.state.deliveryTime = ctx.message.text;
        ctx.reply("📝 Izoh (Comment)?", Markup.keyboard([
            ["Yo'q"],
            [i18n.btn_back_nav, i18n.btn_cancel]
        ]).resize());
        return ctx.wizard.next();
    },
    // Step 7: Comment & Total Calc
    (ctx) => {
        const i18n = ctx.wizard.state.i18n || ctx.i18n;
        const nav = checkNav(ctx);
        if (nav === 'STOP') return;
        if (nav === 'BACK') return ctx.wizard.selectStep(6);

        const text = ctx.message.text;
        ctx.wizard.state.comment = text === "Yo'q" ? "" : text;

        const cart = ctx.session.cart || [];
        const total = cart.reduce((acc, item) => acc + (item.price * item.count), 0);
        ctx.wizard.state.total = total;

        // BTS is strictly Card (handled via pre-set or just flow)
        if (ctx.wizard.state.deliveryMethod === i18n.delivery_bts) {
            // BTS flow usually requires Card payment proof, so we treat it same as Card
            // But existing code jumped to Step 9 directly? 
            // Line 358 in original code: return ctx.wizard.selectStep(9);
            // We keep that behavior or merge it. 
            // Original: 358: if (ctx.wizard.state.deliveryMethod === i18n.delivery_bts) ... selectStep(9)
            // Let's keep existing BTS logic if it was working, but here we are replacing the block.
            // The original code handled BTS specifically at line 358.
            // Let's replicate that logic first.
            ctx.reply(`📨 **BTS Pay**\n\n8600 ...`, navKeyboard(ctx, i18n));
            return ctx.wizard.selectStep(9);
        }

        // Conditional Payment Buttons
        let paymentButtons = [];
        if (ctx.wizard.state.deliveryMethod === i18n.delivery_pickup) {
            // Pickup -> Cash AND Card
            paymentButtons.push([i18n.payment_cash, i18n.payment_card]);
        } else {
            // Yandex (Delivery) -> Card Only
            paymentButtons.push([i18n.payment_card]);
        }
        paymentButtons.push([i18n.btn_back_nav, i18n.btn_cancel]);

        ctx.reply(i18n.payment_select, Markup.keyboard(paymentButtons).resize().oneTime());
        return ctx.wizard.next();
    },
    // Step 8: Payment Method
    async (ctx) => {
        const i18n = ctx.wizard.state.i18n || ctx.i18n;
        const nav = checkNav(ctx);
        if (nav === 'STOP') return;
        if (nav === 'BACK') return ctx.wizard.selectStep(7);

        const choice = ctx.message.text;

        // Validation: Verify if choice is allowed for current delivery method
        // Pickup Logic: Allow both Cash and Card (Relaxed)

        // Delivery Logic: Strict Card Only
        if (ctx.wizard.state.deliveryMethod === i18n.delivery_yandex && choice !== i18n.payment_card) {
            return ctx.reply("⚠️ Yetkazib berish uchun faqat Karta orqali to'lov mavjud.", Markup.keyboard([[i18n.payment_card], [i18n.btn_back_nav, i18n.btn_cancel]]).resize());
        }

        if (choice === i18n.payment_cash) {
            ctx.wizard.state.paymentMethod = 'Naqd';
            return await finishOrder(ctx);
        } else if (choice === i18n.payment_card) {
            ctx.wizard.state.paymentMethod = 'Karta';
            ctx.reply(`💳 **Humo:** 9860 ...\n\nChek yuboring:`, navKeyboard(ctx, i18n));
            return ctx.wizard.next();
        } else {
            ctx.reply("Tanlang.");
        }
    },
    // Step 9: Proof
    async (ctx) => {
        const i18n = ctx.wizard.state.i18n || ctx.i18n;
        const nav = checkNav(ctx);
        if (nav === 'STOP') return;
        if (nav === 'BACK') return ctx.wizard.selectStep(8);

        if (ctx.message.photo) {
            ctx.wizard.state.paymentProof = ctx.message.photo[ctx.message.photo.length - 1].file_id;
            return await finishOrder(ctx);
        } else {
            ctx.reply("⚠️ Chek rasmini yuboring.");
        }
    }
);

module.exports = checkoutScene;