import { NextResponse } from "next/server";
import { getDb } from "@/lib/db";
import bcrypt from "bcryptjs";
import { cookies } from "next/headers";
import { randomUUID } from "crypto";

export async function POST(request: Request) {
  try {
    const sql = getDb();
    const { email, password } = await request.json();

    if (!email || !password) {
      return NextResponse.json(
        { error: "Email and password are required" },
        { status: 400 }
      );
    }

    // Find user
    const users = await sql(
      `SELECT u.*, 
              up.can_view_financial, up.can_edit, up.can_create, up.can_delete, up.can_download,
              up.can_view_dashboard, up.can_view_components, up.can_view_products, up.can_view_customers,
              up.can_view_suppliers, up.can_view_production, up.can_view_stock_history, up.can_view_logistics,
              up.can_view_stock_take, up.can_view_settings
       FROM users u
       LEFT JOIN user_permissions up ON u.id = up.user_id
       WHERE u.email = $1 AND u.is_active = true`,
      [email.toLowerCase()]
    );

    if (users.length === 0) {
      return NextResponse.json(
        { error: "Invalid email or password" },
        { status: 401 }
      );
    }

    const user = users[0];

    // Verify password
    const isValid = await bcrypt.compare(password, user.password_hash);
    if (!isValid) {
      return NextResponse.json(
        { error: "Invalid email or password" },
        { status: 401 }
      );
    }

    // Create session
    const sessionToken = randomUUID();
    const expiresAt = new Date(Date.now() + 7 * 24 * 60 * 60 * 1000); // 7 days

    await sql(
      `INSERT INTO sessions (user_id, token, expires_at) VALUES ($1, $2, $3)`,
      [user.id, sessionToken, expiresAt.toISOString()]
    );

    // Set cookie
    const cookieStore = await cookies();
    cookieStore.set("session_token", sessionToken, {
      httpOnly: true,
      secure: process.env.NODE_ENV === "production",
      sameSite: "lax",
      expires: expiresAt,
      path: "/",
    });

    // Build sections array from individual flags
    const sections: string[] = [];
    if (user.can_view_dashboard) sections.push("dashboard");
    if (user.can_view_components) sections.push("components");
    if (user.can_view_products) sections.push("products");
    if (user.can_view_customers) sections.push("customers");
    if (user.can_view_suppliers) sections.push("suppliers");
    if (user.can_view_production) sections.push("production");
    if (user.can_view_stock_history) sections.push("stock-history");
    if (user.can_view_logistics) sections.push("logistics");
    if (user.can_view_stock_take) sections.push("stock-take");
    if (user.can_view_settings || user.role === "admin") sections.push("settings");

    return NextResponse.json({
      user: {
        id: user.id,
        email: user.email,
        name: user.name,
        role: user.role,
        permissions: {
          sections,
          can_view_financial: user.can_view_financial ?? false,
          can_edit: user.can_edit ?? false,
          can_create: user.can_create ?? false,
          can_delete: user.can_delete ?? false,
          can_download: user.can_download ?? false,
        },
      },
    });
  } catch (error) {
    console.error("Login error:", error);
    return NextResponse.json(
      { error: "Internal server error" },
      { status: 500 }
    );
  }
}