const AppointmentSubmission = require("../models/appointmentSubmission");
const Appointment = require("../models/appointment");

// ==================== CMS ADMIN FUNCTIONS ====================

// Render admin page for appointment management
exports.index = async (req, res) => {
    try {
        let appointment = await Appointment.findOne({ name: "default" });

        // If no data in DB, try to load from JSON file
        if (!appointment) {
            const fs = require("fs");
            const path = require("path");
            const jsonPath = path.join(__dirname, "../data/appointment.json");

            if (fs.existsSync(jsonPath)) {
                const jsonData = JSON.parse(fs.readFileSync(jsonPath, "utf8"));
                appointment = await Appointment.migrateFromJson(jsonData);
            } else {
                // Create default appointment
                appointment = await Appointment.create({
                    name: "default",
                    hero: {
                        title: "Make Appointment",
                        backgroundImage: "",
                        subtitle: "",
                        heading: "",
                        description: "",
                    },
                    visaOptions: [],
                    form: {
                        heading: "Request Appointment",
                        fields: [],
                        submitButton: {
                            text: "Request Appointment",
                            icon: "fa-solid fa-arrow-right",
                            buttonClass: "theme-btn",
                        },
                    },
                });
            }
        }

        const { startDate, endDate } = req.query;
        const query = {};

        if (startDate || endDate) {
            query.createdAt = {};
            if (startDate) {
                query.createdAt.$gte = new Date(startDate);
            }
            if (endDate) {
                // Set end date to end of day
                const end = new Date(endDate);
                end.setHours(23, 59, 59, 999);
                query.createdAt.$lte = end;
            }
        }

        const submissions = await AppointmentSubmission.find(query).sort({ createdAt: -1 }).limit(50);

        res.render("admin/appointment/index", {
            layout: "layouts/main",
            title: "Appointment Management",
            data: appointment,
            submissions,
            startDate,
            endDate,
            user: req.session.user,
            frontendUrl: process.env.FRONTEND_URL || "http://localhost:3000",
        });
    } catch (err) {
        console.error("Error loading appointment admin page:", err);
        req.flash("error", "Error loading appointment data");
        res.redirect("/admin/dashboard");
    }
};

// Update appointment data
exports.update = async (req, res) => {
    try {
        const { hero, visaOptions, form } = req.body;

        // Parse JSON strings if needed
        const heroData = typeof hero === "string" ? JSON.parse(hero) : hero;
        const visaOptionsData = typeof visaOptions === "string" ? JSON.parse(visaOptions) : visaOptions;
        const formData = typeof form === "string" ? JSON.parse(form) : form;

        let appointment = await Appointment.findOne({ name: "default" });

        if (appointment) {
            appointment.hero = heroData;
            appointment.visaOptions = visaOptionsData;
            appointment.form = formData;
            await appointment.save();
        } else {
            appointment = await Appointment.create({
                name: "default",
                hero: heroData,
                visaOptions: visaOptionsData,
                form: formData,
            });
        }

        req.flash("success", "Appointment data updated successfully");
        res.redirect("/admin/appointment");
    } catch (err) {
        console.error("Error updating appointment:", err);
        req.flash("error", "Error updating appointment data");
        res.redirect("/admin/appointment");
    }
};

// API to get appointment data
exports.getAppointmentData = async (req, res) => {
    try {
        let appointment = await Appointment.findOne({ name: "default" });

        if (!appointment) {
            const fs = require("fs");
            const path = require("path");
            const jsonPath = path.join(__dirname, "../data/appointment.json");

            if (fs.existsSync(jsonPath)) {
                const jsonData = JSON.parse(fs.readFileSync(jsonPath, "utf8"));
                appointment = await Appointment.migrateFromJson(jsonData);
            }
        }

        res.json({
            success: true,
            data: appointment,
        });
    } catch (err) {
        console.error("Error getting appointment data:", err);
        res.status(500).json({
            success: false,
            error: "Error loading appointment data",
        });
    }
};

// Public API to get appointment page data (for frontend)
exports.api = async (req, res) => {
    try {
        let appointment = await Appointment.findOne({ name: "default" });

        if (!appointment) {
            const fs = require("fs");
            const path = require("path");
            const jsonPath = path.join(__dirname, "../data/appointment.json");

            if (fs.existsSync(jsonPath)) {
                const jsonData = JSON.parse(fs.readFileSync(jsonPath, "utf8"));
                appointment = await Appointment.migrateFromJson(jsonData);
            }
        }

        if (!appointment) {
            return res.status(404).json({
                success: false,
                error: "Appointment data not found",
            });
        }

        res.json({
            success: true,
            data: {
                hero: appointment.hero,
                visaOptions: appointment.visaOptions,
                form: appointment.form,
            },
        });
    } catch (err) {
        console.error("Error getting appointment API data:", err);
        res.status(500).json({
            success: false,
            error: "Error loading appointment data",
        });
    }
};

// ==================== APPOINTMENT SUBMISSIONS API ====================

// API để submit appointment form (từ frontend)
exports.submitAppointment = async (req, res) => {
    try {
        const { name, email, phone, address, appointmentDate, message, visaTypes } = req.body;

        // Validation
        if (!name || !email) {
            return res.status(400).json({
                success: false,
                error: "Name and email are required",
            });
        }

        // Create new submission
        const submission = new AppointmentSubmission({
            name: name.trim(),
            email: email.trim().toLowerCase(),
            phone: phone?.trim() || "",
            address: address?.trim() || "",
            appointmentDate: appointmentDate?.trim() || "",
            message: message?.trim() || "",
            visaTypes: Array.isArray(visaTypes) ? visaTypes : [],
            ipAddress: req.ip || req.connection?.remoteAddress || "",
            userAgent: req.get("User-Agent") || "",
        });

        await submission.save();

        res.status(201).json({
            success: true,
            message: "Thank you! Your appointment request has been submitted. We will contact you soon.",
            data: {
                id: submission._id,
                name: submission.name,
                email: submission.email,
                appointmentDate: submission.appointmentDate,
            },
        });
    } catch (err) {
        console.error("Error submitting appointment:", err);

        // Handle validation errors
        if (err.name === "ValidationError") {
            const errors = Object.values(err.errors).map((e) => e.message);
            return res.status(400).json({
                success: false,
                error: errors.join(", "),
            });
        }

        res.status(500).json({
            success: false,
            error: "Error submitting appointment. Please try again later.",
        });
    }
};

// API để lấy danh sách appointments (cho admin)
exports.getAppointments = async (req, res) => {
    try {
        const { status, page = 1, limit = 20 } = req.query;

        const query = {};
        if (status && ["pending", "confirmed", "completed", "cancelled"].includes(status)) {
            query.status = status;
        }

        const skip = (parseInt(page) - 1) * parseInt(limit);

        const [appointments, total] = await Promise.all([
            AppointmentSubmission.find(query)
                .sort({ createdAt: -1 })
                .skip(skip)
                .limit(parseInt(limit)),
            AppointmentSubmission.countDocuments(query),
        ]);

        res.json({
            success: true,
            data: appointments,
            pagination: {
                page: parseInt(page),
                limit: parseInt(limit),
                total,
                totalPages: Math.ceil(total / parseInt(limit)),
            },
        });
    } catch (err) {
        console.error("Error getting appointments:", err);
        res.status(500).json({
            success: false,
            error: "Error loading appointments",
        });
    }
};

// API để cập nhật status của appointment
exports.updateAppointmentStatus = async (req, res) => {
    try {
        const { id } = req.params;
        const { status, notes } = req.body;

        const validStatuses = ["pending", "confirmed", "completed", "cancelled"];
        if (!validStatuses.includes(status)) {
            return res.status(400).json({
                success: false,
                error: "Invalid status",
            });
        }

        const updateData = { status };
        if (notes !== undefined) updateData.notes = notes;
        if (status === "confirmed") updateData.confirmedAt = new Date();
        if (status === "completed") updateData.completedAt = new Date();

        const appointment = await AppointmentSubmission.findByIdAndUpdate(
            id,
            updateData,
            { new: true }
        );

        if (!appointment) {
            return res.status(404).json({
                success: false,
                error: "Appointment not found",
            });
        }

        res.json({
            success: true,
            data: appointment,
        });
    } catch (err) {
        console.error("Error updating appointment:", err);
        res.status(500).json({
            success: false,
            error: "Error updating appointment",
        });
    }
};

// API để lấy chi tiết một appointment
exports.getAppointmentById = async (req, res) => {
    try {
        const { id } = req.params;
        const appointment = await AppointmentSubmission.findById(id);

        if (!appointment) {
            return res.status(404).json({
                success: false,
                error: "Appointment not found",
            });
        }

        res.json({
            success: true,
            data: appointment,
        });
    } catch (err) {
        console.error("Error getting appointment:", err);
        res.status(500).json({
            success: false,
            error: "Error loading appointment",
        });
    }
};

// API để xóa appointment
exports.deleteAppointment = async (req, res) => {
    try {
        const { id } = req.params;
        const appointment = await AppointmentSubmission.findByIdAndDelete(id);

        if (!appointment) {
            return res.status(404).json({
                success: false,
                error: "Appointment not found",
            });
        }

        res.json({
            success: true,
            message: "Appointment deleted successfully",
        });
    } catch (err) {
        console.error("Error deleting appointment:", err);
        res.status(500).json({
            success: false,
            error: "Error deleting appointment",
        });
    }
};