export const dynamic = 'force-dynamic';

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

async function canAccessTask(userId: string, isAdmin: boolean, accessibleProjectIds: string[], taskId: string) {
  if (isAdmin) return { ok: true as const };
  const { data: task, error } = await supabase
    .from('tasks')
    .select('id,project_id,owner_user_id,executor_ids,help_requested_to_user_id')
    .eq('id', taskId)
    .maybeSingle();
  if (error) return { ok: false as const, status: 500, error: error.message };
  if (!task) return { ok: false as const, status: 404, error: '计划不存在' };
  if (task.project_id && accessibleProjectIds.includes(task.project_id)) return { ok: true as const };
  if (task.owner_user_id === userId) return { ok: true as const };
  if (task.help_requested_to_user_id === userId) return { ok: true as const };
  if (Array.isArray(task.executor_ids) && task.executor_ids.includes(userId)) return { ok: true as const };
  return { ok: false as const, status: 403, error: '无权限' };
}

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 task_id = searchParams.get('task_id');
  const help_requested_to_user_id = searchParams.get('help_requested_to_user_id');

  let query = supabase
    .from('task_steps')
    .select(`
      *,
      task:tasks(
        id,
        title,
        project_id,
        kr_id,
        owner_user_id,
        help_requested_to_user_id,
        help_requested_by_user_id,
        help_requested_at
      )
    `)
    .order('created_at', { ascending: false });

  if (!ctx!.isAdmin) {
    if (help_requested_to_user_id && help_requested_to_user_id !== ctx!.user.id) {
      return NextResponse.json({ error: '无权限' }, { status: 403 });
    }
    if (task_id) {
      const access = await canAccessTask(ctx!.user.id, ctx!.isAdmin, ctx!.accessibleProjectIds, task_id);
      if (!access.ok) {
        return NextResponse.json({ error: access.error }, { status: access.status });
      }
    }
    if (!task_id && !help_requested_to_user_id) {
      query = query.or(`executor_id.eq.${ctx!.user.id},help_requested_to_user_id.eq.${ctx!.user.id}`);
    }
  }

  if (task_id) query = query.eq('task_id', task_id);
  if (help_requested_to_user_id) query = query.eq('help_requested_to_user_id', help_requested_to_user_id);

  const { data, error } = await query;

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

  return NextResponse.json(data);
}

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 {
    task_id,
    content,
    note,
    executor_id,
    start_date,
    end_date,
    is_completed,
    help_requested_to_user_id,
    help_requested_by_user_id,
  } = body;

  const isHelpRequested = Boolean(help_requested_to_user_id);

  if (!task_id) {
    return NextResponse.json({ error: '计划ID为必填项' }, { status: 400 });
  }

  const access = await canAccessTask(ctx!.user.id, ctx!.isAdmin, ctx!.accessibleProjectIds, task_id);
  if (!access.ok) {
    return NextResponse.json({ error: access.error }, { status: access.status });
  }

  const { data, error } = await supabase
    .from('task_steps')
    .insert({
      task_id,
      content,
      note,
      executor_id,
      start_date,
      end_date,
      is_completed,
      help_requested_to_user_id: help_requested_to_user_id || null,
      help_requested_by_user_id: isHelpRequested ? (ctx!.isAdmin ? (help_requested_by_user_id || null) : ctx!.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);
}

export async function PATCH(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 {
    id,
    content,
    note,
    executor_id,
    start_date,
    end_date,
    is_completed,
    help_requested_to_user_id,
    help_requested_by_user_id,
  } = body;

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

  const { data: stepRow, error: stepErr } = await supabase
    .from('task_steps')
    .select('id,task_id')
    .eq('id', id)
    .maybeSingle();
  if (stepErr) return NextResponse.json({ error: stepErr.message }, { status: 500 });
  if (!stepRow) return NextResponse.json({ error: '步骤不存在' }, { status: 404 });

  const access = await canAccessTask(ctx!.user.id, ctx!.isAdmin, ctx!.accessibleProjectIds, stepRow.task_id);
  if (!access.ok) {
    return NextResponse.json({ error: access.error }, { status: access.status });
  }

  const updateData: Record<string, unknown> = {};
  if (content !== undefined) updateData.content = content;
  if (note !== undefined) updateData.note = note;
  if (executor_id !== undefined) updateData.executor_id = executor_id;
  if (start_date !== undefined) updateData.start_date = start_date;
  if (end_date !== undefined) updateData.end_date = end_date;
  if (is_completed !== undefined) updateData.is_completed = is_completed;

  if (help_requested_to_user_id !== undefined) {
    updateData.help_requested_to_user_id = help_requested_to_user_id;
    if (help_requested_to_user_id) {
      updateData.help_requested_by_user_id = ctx!.isAdmin ? (help_requested_by_user_id || null) : ctx!.user.id;
      updateData.help_requested_at = new Date().toISOString();
    } else {
      updateData.help_requested_by_user_id = null;
      updateData.help_requested_at = null;
    }
  }

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

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

  return NextResponse.json(data);
}

export async function DELETE(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 id = searchParams.get('id');

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

  const { data: stepRow, error: stepErr } = await supabase
    .from('task_steps')
    .select('id,task_id')
    .eq('id', id)
    .maybeSingle();
  if (stepErr) return NextResponse.json({ error: stepErr.message }, { status: 500 });
  if (!stepRow) return NextResponse.json({ error: '步骤不存在' }, { status: 404 });

  const access = await canAccessTask(ctx!.user.id, ctx!.isAdmin, ctx!.accessibleProjectIds, stepRow.task_id);
  if (!access.ok) {
    return NextResponse.json({ error: access.error }, { status: access.status });
  }

  const { error } = await supabase
    .from('task_steps')
    .delete()
    .eq('id', id);

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

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