import { NextResponse } from 'next/server';
import { db, writerDb } from "@/drizzle/db";
import { users, tenants, systemFeatures, saasPackages } from "@/drizzle/schema";
import { eq } from 'drizzle-orm';
import { cookies } from 'next/headers';
import jwt from 'jsonwebtoken';
import bcrypt from 'bcryptjs';

export const dynamic = 'force-dynamic';

export async function GET(_req: Request) {
  try {
    const cookieStore = await cookies();
    const token = cookieStore.get('jumpa_token')?.value;

    if (!token) return NextResponse.json({ error: 'Unauthorized' }, { status: 401 });

    const decoded = jwt.verify(token, process.env.JWT_SECRET as string) as { email: string; role: string; tenantId: string };
    
    if (decoded.role !== 'admin' && decoded.role !== 'superadmin') {
      return NextResponse.json({ error: 'Forbidden: Admins only' }, { status: 403 });
    }

    // Ambil semua user di tenant ini
    const tenantUsers = await db.select({
      id: users.id,
      email: users.email,
      role: users.role,
      licenses: users.licenses,
      createdAt: users.createdAt
    }).from(users).where(eq(users.tenantId, decoded.tenantId));

    // Ambil status Closed Group tenant ini
    const tenantData = await db.select({
      id: tenants.id,
      allowCrossGroup: tenants.allowCrossGroup,
      name: tenants.name,
      licenses: tenants.licenses,
      licenseNumber: tenants.licenseNumber,
      packageId: tenants.packageId,
      brandColor: tenants.brandColor,
      platformName: tenants.platformName,
      securityTier: tenants.securityTier,
      byokEnabled: tenants.byokEnabled,
      byokKey: tenants.byokKey
    }).from(tenants).where(eq(tenants.id, decoded.tenantId)).limit(1);

    // Ambil system features
    const allFeatures = await db.select().from(systemFeatures);
    
    // Gabungkan Package Features jika Tenant memiliki Paket
    let mergedLicenses = tenantData[0].licenses;
    if (tenantData[0].packageId) {
       const pkgData = await db.select().from(saasPackages).where(eq(saasPackages.id, tenantData[0].packageId)).limit(1);
       if (pkgData.length > 0) {
          try {
             let tenantCustom: Record<string, string> = {};
             if (typeof mergedLicenses === 'string') tenantCustom = JSON.parse(mergedLicenses) || {};
             else tenantCustom = (mergedLicenses as any) || {};

             const pkgFeats: string[] = JSON.parse(pkgData[0].features || "[]");
             pkgFeats.forEach(f => {
                tenantCustom[f] = "GRANTED";
             });
             mergedLicenses = JSON.stringify(tenantCustom);
          } catch(e) {}
       }
    }
    
    const finalTenant = {
      ...tenantData[0],
      licenses: mergedLicenses
    };

    return NextResponse.json({
      users: tenantUsers,
      tenant: finalTenant,
      systemFeatures: allFeatures
    });
  } catch (error: any) {
    console.error('[ADMIN GET ERROR]', error);
    return NextResponse.json({ error: error.message || 'Internal Server Error' }, { status: 500 });
  }
}

export async function POST(req: Request) {
  try {
    const cookieStore = await cookies();
    const token = cookieStore.get('jumpa_token')?.value;
    if (!token) return NextResponse.json({ error: 'Unauthorized' }, { status: 401 });

    const decoded = jwt.verify(token, process.env.JWT_SECRET as string) as { email: string; role: string; tenantId: string };
    if (decoded.role !== 'admin' && decoded.role !== 'superadmin') return NextResponse.json({ error: 'Forbidden' }, { status: 403 });

    const body = await req.json();

    if (body.action === 'toggle_cross_group') {
      const newStatus = !!body.allowCrossGroup;
      await writerDb.update(tenants)
        .set({ allowCrossGroup: newStatus })
        .where(eq(tenants.id, decoded.tenantId));
      
      return NextResponse.json({ success: true, allowCrossGroup: newStatus });
    }

    if (body.action === 'add_user') {
      const { email, password, role } = body;
      if (!email || !password || password.length < 6) {
        return NextResponse.json({ error: 'Email and password (min 6 chars) are required' }, { status: 400 });
      }

      // Check if email already exists
      const existingUser = await db.select().from(users).where(eq(users.email, email)).limit(1);
      if (existingUser.length > 0) {
        return NextResponse.json({ error: 'Email sudah terdaftar.' }, { status: 409 });
      }

      // Create the user with bcrypt-hashed password (Kelas Militer)
      const hashedPassword = await bcrypt.hash(password, 12);
      const newUserResult = await writerDb.insert(users).values({
        email: email,
        passwordHash: hashedPassword,
        tenantId: decoded.tenantId,
        role: role || 'user'
      }).returning({ id: users.id, email: users.email, role: users.role, createdAt: users.createdAt });

      return NextResponse.json({ success: true, user: newUserResult[0] });
    }

    if (body.action === 'change_package') {
      const { newLicenses } = body; // Array of strings e.g. ["chat", "vc"]
      if (!Array.isArray(newLicenses)) {
        return NextResponse.json({ error: 'Invalid licenses format' }, { status: 400 });
      }

      const licensesStr = JSON.stringify(newLicenses);
      await writerDb.update(tenants)
        .set({ licenses: licensesStr })
        .where(eq(tenants.id, decoded.tenantId));

      return NextResponse.json({ success: true, licenses: licensesStr });
    }

    if (body.action === 'update_white_label') {
      const { brandColor, platformName } = body;
      await writerDb.update(tenants)
        .set({ brandColor, platformName })
        .where(eq(tenants.id, decoded.tenantId));

      return NextResponse.json({ success: true });
    }

    if (body.action === 'update_user_licenses') {
      const { targetUserId, newLicenses, byokEnabled, byokKey } = body;
      
      // Pastikan targetUser ada di tenant yang sama
      const targetUserCheck = await db.select().from(users).where(eq(users.id, targetUserId)).limit(1);
      if (targetUserCheck.length === 0 || targetUserCheck[0].tenantId !== decoded.tenantId) {
        return NextResponse.json({ error: 'User not found or access denied' }, { status: 403 });
      }

      const updateData: any = { licenses: JSON.stringify(newLicenses) };
      if (typeof byokEnabled === 'boolean') updateData.byokEnabled = byokEnabled;
      if (typeof byokKey === 'string') updateData.byokKey = byokKey;

      await writerDb.update(users)
        .set(updateData)
        .where(eq(users.id, targetUserId));

      return NextResponse.json({ success: true });
    }

    if (body.action === 'edit_user') {
      const { id, email, role, password } = body;
      
      const targetUserCheck = await db.select().from(users).where(eq(users.id, id)).limit(1);
      if (targetUserCheck.length === 0 || targetUserCheck[0].tenantId !== decoded.tenantId) {
        return NextResponse.json({ error: 'User not found or access denied' }, { status: 403 });
      }

      const updateData: Record<string, string> = { email, role };
      if (password && password.trim() !== '') {
        updateData.passwordHash = await bcrypt.hash(password, 12);
      }

      await writerDb.update(users).set(updateData).where(eq(users.id, id));
      return NextResponse.json({ success: true });
    }

    if (body.action === 'bulk_delete') {
      const { userIds } = body; // Array of strings
      if (!Array.isArray(userIds) || userIds.length === 0) return NextResponse.json({ success: true });

      // Ensure we only delete users from this tenant
      for (const uid of userIds) {
        const uCheck = await db.select().from(users).where(eq(users.id, uid)).limit(1);
        if (uCheck.length > 0 && uCheck[0].tenantId === decoded.tenantId) {
          await writerDb.delete(users).where(eq(users.id, uid));
        }
      }
      return NextResponse.json({ success: true });
    }

    if (body.action === 'update_tenant_byok') {
      const { byokEnabled, byokKey } = body;
      
      // Ensure the tenant has BYOK allowed by Supreme Admin
      const tenantCheck = await db.select().from(tenants).where(eq(tenants.id, decoded.tenantId)).limit(1);
      if (!tenantCheck[0].byokEnabled && byokEnabled) {
        return NextResponse.json({ error: 'BYOK not enabled for this tenant by Supreme Admin.' }, { status: 403 });
      }

      await writerDb.update(tenants)
        .set({ byokEnabled, byokKey })
        .where(eq(tenants.id, decoded.tenantId));
      
      return NextResponse.json({ success: true });
    }

    if (body.action === 'update_user_byok') {
      const { targetUserId, byokEnabled, byokKey } = body;
      
      const targetUserCheck = await db.select().from(users).where(eq(users.id, targetUserId)).limit(1);
      if (targetUserCheck.length === 0 || targetUserCheck[0].tenantId !== decoded.tenantId) {
        return NextResponse.json({ error: 'User not found or access denied' }, { status: 403 });
      }

      await writerDb.update(users)
        .set({ byokEnabled: !!byokEnabled, byokKey: byokKey })
        .where(eq(users.id, targetUserId));

      return NextResponse.json({ success: true });
    }

    return NextResponse.json({ error: 'Invalid action' }, { status: 400 });
  } catch (e) {
    console.error("[API/ADMIN POST Error]", e);
    return NextResponse.json({ error: 'Internal Server Error' }, { status: 500 });
  }
}