export const dynamic = 'force-dynamic';

import { NextRequest, NextResponse } from 'next/server';
import { supabase } from '@/lib/supabase';
import { ensureAuthenticated, getAuthContext, hasProjectAccess } from '@/lib/access-control';

export async function GET(request: NextRequest) {
  const ctx = await getAuthContext(request);
  const auth = ensureAuthenticated(ctx);
  if (!auth.ok) {
    return NextResponse.json({ error: auth.error }, { status: auth.status });
  }

  const searchParams = request.nextUrl.searchParams;
  const kr_id = searchParams.get('kr_id');
  const project_id = searchParams.get('project_id');
  const user_id = searchParams.get('user_id');
  const help_requested_to_user_id = searchParams.get('help_requested_to_user_id');
  const include_help = searchParams.get('include_help') === 'true';

  if (!ctx!.isAdmin) {
    if (user_id && user_id !== ctx!.user.id) {
      return NextResponse.json({ error: '无权限' }, { status: 403 });
    }
    if (help_requested_to_user_id && help_requested_to_user_id !== ctx!.user.id) {
      return NextResponse.json({ error: '无权限' }, { status: 403 });
    }
    if (project_id && !hasProjectAccess(ctx!, project_id)) {
      return NextResponse.json({ error: '无权限' }, { status: 403 });
    }
    if (kr_id) {
      const { data: kr, error: krErr } = await supabase
        .from('krs')
        .select('id,project_id')
        .eq('id', kr_id)
        .maybeSingle();
      if (krErr) return NextResponse.json({ error: krErr.message }, { status: 500 });
      if (!kr) return NextResponse.json({ error: 'KR不存在' }, { status: 404 });
      if (!hasProjectAccess(ctx!, kr.project_id)) {
        return NextResponse.json({ error: '无权限' }, { status: 403 });
      }
    }
  }

  const baseQuery = () =>
    supabase
    .from('tasks')
    .select(`
      *,
      steps:task_steps(*)
    `)
    .order('created_at', { ascending: false });

  const applyParams = (query: ReturnType<typeof baseQuery>) => {
    let q = query;
    if (kr_id) {
      q = q.eq('kr_id', kr_id);
    } else if (project_id) {
      q = q.eq('project_id', project_id).is('kr_id', null);
    }

    if (help_requested_to_user_id) {
      q = q.eq('help_requested_to_user_id', help_requested_to_user_id);
    } else if (user_id) {
      if (include_help) {
        q = q.or(`owner_user_id.eq.${user_id},help_requested_to_user_id.eq.${user_id}`);
      } else {
        q = q.eq('owner_user_id', user_id);
      }
    }

    return q;
  };

  if (ctx!.isAdmin) {
    const { data, error } = await applyParams(baseQuery());
    if (error) {
      return NextResponse.json({ error: error.message }, { status: 500 });
    }
    return NextResponse.json(data);
  }

  if (project_id || kr_id) {
    const { data, error } = await applyParams(baseQuery());
    if (error) {
      return NextResponse.json({ error: error.message }, { status: 500 });
    }
    return NextResponse.json(data);
  }

  const relatedTasks = new Map<string, any>();
  const addRows = (rows: any[] | null) => {
    if (!rows) return;
    for (const row of rows) {
      relatedTasks.set(row.id, row);
    }
  };

  const projectIds = ctx!.accessibleProjectIds;

  const builders: any[] = [];
  if (projectIds.length > 0) {
    builders.push(applyParams(baseQuery().in('project_id', projectIds)));
  }
  builders.push(applyParams(baseQuery().or(`owner_user_id.eq.${ctx!.user.id},help_requested_to_user_id.eq.${ctx!.user.id}`)));
  builders.push(applyParams(baseQuery().contains('executor_ids', [ctx!.user.id])));

  const results = await Promise.all(builders.map(b => b));
  for (const r of results) {
    if (r.error) {
      return NextResponse.json({ error: r.error.message }, { status: 500 });
    }
    addRows(r.data);
  }

  return NextResponse.json(Array.from(relatedTasks.values()));
}

export async function POST(request: NextRequest) {
  const ctx = await getAuthContext(request);
  const auth = ensureAuthenticated(ctx);
  if (!auth.ok) {
    return NextResponse.json({ error: auth.error }, { status: auth.status });
  }

  const body = await request.json();
  const {
    kr_id,
    project_id,
    title,
    description,
    status,
    priority,
    urgency,
    owner_user_id,
    executor_ids,
    start_date,
    end_date,
    help_requested_to_user_id,
    help_requested_by_user_id,
  } = body;

  const isHelpRequested = Boolean(help_requested_to_user_id);

  if (!ctx!.isAdmin) {
    if (project_id && !hasProjectAccess(ctx!, project_id)) {
      return NextResponse.json({ error: '无权限' }, { status: 403 });
    }
    if (kr_id) {
      const { data: kr, error: krErr } = await supabase
        .from('krs')
        .select('id,project_id')
        .eq('id', kr_id)
        .maybeSingle();
      if (krErr) return NextResponse.json({ error: krErr.message }, { status: 500 });
      if (!kr) return NextResponse.json({ error: 'KR不存在' }, { status: 404 });
      if (!hasProjectAccess(ctx!, kr.project_id)) {
        return NextResponse.json({ error: '无权限' }, { status: 403 });
      }
    }
  }

  const { data, error } = await supabase
    .from('tasks')
    .insert({
      kr_id: kr_id || null,
      project_id: project_id || null,
      title,
      description,
      status: status || 'todo',
      priority: priority || 3,
      urgency: urgency || 3,
      owner_user_id,
      executor_ids: executor_ids || [],
      start_date,
      end_date,
      help_requested_to_user_id: help_requested_to_user_id || null,
      help_requested_by_user_id: help_requested_by_user_id || null,
      help_requested_at: isHelpRequested ? new Date().toISOString() : null,
    })
    .select()
    .single();

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

  return NextResponse.json(data);
}