import type { APIRoute } from 'astro';
import { db } from '../../../db';
import { timeEntries, members, users, clients, categories } from '../../../db/schema';
import { eq, and, gte, lte, desc } from 'drizzle-orm';

export const GET: APIRoute = async ({ request, locals, cookies }) => {
  const user = locals.user;
  if (!user) {
    return new Response('Unauthorized', { status: 401 });
  }

  // Get current team from cookie
  const currentTeamId = cookies.get('currentTeamId')?.value;

  const userMemberships = await db.select()
    .from(members)
    .where(eq(members.userId, user.id))
    .all();

  if (userMemberships.length === 0) {
    return new Response('No organization found', { status: 404 });
  }

  // Use current team or fallback to first membership
  const userMembership = currentTeamId
    ? userMemberships.find(m => m.organizationId === currentTeamId) || userMemberships[0]
    : userMemberships[0];

  const url = new URL(request.url);
  const selectedMemberId = url.searchParams.get('member') || '';
  const selectedCategoryId = url.searchParams.get('category') || '';
  const selectedClientId = url.searchParams.get('client') || '';
  const timeRange = url.searchParams.get('range') || 'week';
  const customFrom = url.searchParams.get('from');
  const customTo = url.searchParams.get('to');

  const now = new Date();
  let startDate = new Date();
  let endDate = new Date();

  switch (timeRange) {
    case 'today':
      startDate.setHours(0, 0, 0, 0);
      endDate.setHours(23, 59, 59, 999);
      break;
    case 'week':
      startDate.setDate(now.getDate() - 7);
      break;
    case 'month':
      startDate.setMonth(now.getMonth() - 1);
      break;
    case 'mtd':
      startDate = new Date(now.getFullYear(), now.getMonth(), 1);
      break;
    case 'ytd':
      startDate = new Date(now.getFullYear(), 0, 1);
      break;
    case 'last-month':
      startDate = new Date(now.getFullYear(), now.getMonth() - 1, 1);
      endDate = new Date(now.getFullYear(), now.getMonth(), 0, 23, 59, 59, 999);
      break;
    case 'custom':
      if (customFrom) {
        const parts = customFrom.split('-');
        startDate = new Date(parseInt(parts[0]), parseInt(parts[1]) - 1, parseInt(parts[2]), 0, 0, 0, 0);
      }
      if (customTo) {
        const parts = customTo.split('-');
        endDate = new Date(parseInt(parts[0]), parseInt(parts[1]) - 1, parseInt(parts[2]), 23, 59, 59, 999);
      }
      break;
  }

  const conditions = [
    eq(timeEntries.organizationId, userMembership.organizationId),
    gte(timeEntries.startTime, startDate),
    lte(timeEntries.startTime, endDate),
  ];

  if (selectedMemberId) {
    conditions.push(eq(timeEntries.userId, selectedMemberId));
  }

  if (selectedCategoryId) {
    conditions.push(eq(timeEntries.categoryId, selectedCategoryId));
  }

  if (selectedClientId) {
    conditions.push(eq(timeEntries.clientId, selectedClientId));
  }

  const entries = await db.select({
    entry: timeEntries,
    user: users,
    client: clients,
    category: categories,
  })
    .from(timeEntries)
    .innerJoin(users, eq(timeEntries.userId, users.id))
    .innerJoin(clients, eq(timeEntries.clientId, clients.id))
    .innerJoin(categories, eq(timeEntries.categoryId, categories.id))
    .where(and(...conditions))
    .orderBy(desc(timeEntries.startTime))
    .all();

  // Generate CSV
  const headers = ['Date', 'Start Time', 'End Time', 'Duration (h)', 'Member', 'Client', 'Category', 'Description'];
  const rows = entries.map(e => {
    const start = e.entry.startTime;
    const end = e.entry.endTime;

    let duration = 0;
    if (end) {
      duration = (end.getTime() - start.getTime()) / (1000 * 60 * 60); // Hours
    }

    return [
      start.toLocaleDateString(),
      start.toLocaleTimeString(),
      end ? end.toLocaleTimeString() : '',
      end ? duration.toFixed(2) : 'Running',
      `"${(e.user.name || '').replace(/"/g, '""')}"`,
      `"${(e.client.name || '').replace(/"/g, '""')}"`,
      `"${(e.category.name || '').replace(/"/g, '""')}"`,
      `"${(e.entry.description || '').replace(/"/g, '""')}"`
    ].join(',');
  });

  const csvContent = [headers.join(','), ...rows].join('\n');

  return new Response(csvContent, {
    headers: {
      'Content-Type': 'text/csv',
      'Content-Disposition': `attachment; filename="time-entries-${startDate.toISOString().split('T')[0]}-to-${endDate.toISOString().split('T')[0]}.csv"`,
    },
  });
};