import { NextRequest, NextResponse } from 'next/server';
import { createClient } from '@/lib/supabase/server';

// GET /api/admin/users — list all users + pending invitations
export async function GET(req: NextRequest) {
  const supabase = await createClient();
  const { data: { user } } = await supabase.auth.getUser();
  if (!user) return NextResponse.json({ error: 'Unauthorized' }, { status: 401 });

  const { searchParams } = new URL(req.url);
  const tab = searchParams.get('tab') || 'users';

  if (tab === 'invitations') {
    const { data, error } = await supabase
      .from('contributor_invitations')
      .select('*')
      .order('created_at', { ascending: false });
    if (error) return NextResponse.json({ error: error.message }, { status: 500 });
    return NextResponse.json({ invitations: data || [] });
  }

  // Users tab
  const { data, error } = await supabase
    .from('user_profiles')
    .select('id, email, full_name, avatar_url, role, is_active, created_at')
    .order('created_at', { ascending: false });

  if (error) return NextResponse.json({ error: error.message }, { status: 500 });
  return NextResponse.json({ users: data || [] });
}

// PATCH /api/admin/users — update user role or status
export async function PATCH(req: NextRequest) {
  const supabase = await createClient();
  const { data: { user } } = await supabase.auth.getUser();
  if (!user) return NextResponse.json({ error: 'Unauthorized' }, { status: 401 });

  const body = await req.json();
  const { id, updates } = body;

  if (!id || !updates) {
    return NextResponse.json({ error: 'Missing id or updates' }, { status: 400 });
  }

  const { data, error } = await supabase
    .from('user_profiles')
    .update(updates)
    .eq('id', id)
    .select()
    .single();

  if (error) return NextResponse.json({ error: error.message }, { status: 500 });
  return NextResponse.json({ user: data });
}

// POST /api/admin/users — send contributor invitation
export async function POST(req: NextRequest) {
  const supabase = await createClient();
  const { data: { user } } = await supabase.auth.getUser();
  if (!user) return NextResponse.json({ error: 'Unauthorized' }, { status: 401 });

  const body = await req.json();
  const { email, role, message } = body;

  if (!email) {
    return NextResponse.json({ error: 'Email is required' }, { status: 400 });
  }

  // Get inviter profile
  const { data: inviterProfile } = await supabase
    .from('user_profiles')
    .select('full_name, email')
    .eq('id', user.id)
    .single();

  // Generate unique token
  const token = crypto.randomUUID().replace(/-/g, '') + crypto.randomUUID().replace(/-/g, '');

  // Check for existing pending invitation
  const { data: existing } = await supabase
    .from('contributor_invitations')
    .select('id, status')
    .eq('email', email)
    .eq('status', 'pending')
    .single();

  if (existing) {
    return NextResponse.json({ error: 'A pending invitation already exists for this email' }, { status: 409 });
  }

  // Insert invitation record
  const { data: invitation, error: insertError } = await supabase
    .from('contributor_invitations')
    .insert({
      email,
      invited_by: user.id,
      role: role || 'contributor',
      token,
      message: message || null,
      status: 'pending',
    })
    .select()
    .single();

  if (insertError) return NextResponse.json({ error: insertError.message }, { status: 500 });

  // Send email via Supabase Edge Function
  const supabaseUrl = process.env.NEXT_PUBLIC_SUPABASE_URL;
  const supabaseAnonKey = process.env.NEXT_PUBLIC_SUPABASE_ANON_KEY;
  const siteUrl = process.env.NEXT_PUBLIC_SITE_URL || 'https://broadcastbeat.com';

  try {
    const emailRes = await fetch(`${supabaseUrl}/functions/v1/send-contributor-invite`, {
      method: 'POST',
      headers: {
        'Content-Type': 'application/json',
        'Authorization': `Bearer ${supabaseAnonKey}`,
      },
      body: JSON.stringify({
        email,
        inviterName: inviterProfile?.full_name || inviterProfile?.email || 'Broadcast Beat Admin',
        role: role || 'contributor',
        token,
        message,
        siteUrl,
      }),
    });

    if (!emailRes.ok) {
      // Mark invitation as failed but still return the record
      await supabase
        .from('contributor_invitations')
        .update({ status: 'email_failed' })
        .eq('id', invitation.id);
      return NextResponse.json({ invitation, emailSent: false, warning: 'Invitation created but email failed to send' });
    }
  } catch {
    return NextResponse.json({ invitation, emailSent: false, warning: 'Invitation created but email failed to send' });
  }

  return NextResponse.json({ invitation, emailSent: true });
}

// DELETE /api/admin/users — revoke invitation
export async function DELETE(req: NextRequest) {
  const supabase = await createClient();
  const { data: { user } } = await supabase.auth.getUser();
  if (!user) return NextResponse.json({ error: 'Unauthorized' }, { status: 401 });

  const body = await req.json();
  const { invitationId } = body;

  if (!invitationId) {
    return NextResponse.json({ error: 'invitationId is required' }, { status: 400 });
  }

  const { error } = await supabase
    .from('contributor_invitations')
    .update({ status: 'revoked' })
    .eq('id', invitationId);

  if (error) return NextResponse.json({ error: error.message }, { status: 500 });
  return NextResponse.json({ success: true });
}