import { NextRequest, NextResponse } from "next/server";
import { getServerSession } from "next-auth/next";
import { authOptions } from "@/app/api/auth/[...nextauth]/route";

interface Task {
  id: string;
  headline: string;
  projectName: string;
  projectId: number;
  status: number;
  dueDate: string | null;
  milestone: string | null;
  details: string | null;
}

async function getLeantimeUserId(email: string): Promise<number | null> {
  try {
    if (!process.env.LEANTIME_TOKEN) {
      console.error('LEANTIME_TOKEN is not set in environment variables');
      return null;
    }

    console.log('Fetching Leantime users for email:', email);
    const response = await fetch(`${process.env.LEANTIME_API_URL}/api/jsonrpc`, {
      method: 'POST',
      headers: {
        'Content-Type': 'application/json',
        'apiKey': process.env.LEANTIME_TOKEN
      },
      body: JSON.stringify({
        jsonrpc: '2.0',
        method: 'leantime.rpc.users.getAll',
        id: 1
      }),
    });

    const responseText = await response.text();
    console.log('Raw Leantime response:', responseText);

    if (!response.ok) {
      console.error('Failed to fetch Leantime users:', {
        status: response.status,
        statusText: response.statusText,
        headers: Object.fromEntries(response.headers.entries())
      });
      return null;
    }

    let data;
    try {
      data = JSON.parse(responseText);
    } catch (e) {
      console.error('Failed to parse Leantime response:', e);
      return null;
    }

    console.log('Leantime users response:', data);

    if (!data.result || !Array.isArray(data.result)) {
      console.error('Invalid response format from Leantime users API');
      return null;
    }

    const users = data.result;
    const user = users.find((u: any) => u.email === email);
    
    if (user) {
      console.log('Found Leantime user:', { id: user.id, email: user.email });
    } else {
      console.log('No Leantime user found for email:', email);
    }
    
    return user ? user.id : null;
  } catch (error) {
    console.error('Error fetching Leantime user ID:', error);
    return null;
  }
}

export async function GET(request: NextRequest) {
  try {
    const session = await getServerSession(authOptions);
    if (!session?.user?.email) {
      return NextResponse.json({ error: "Unauthorized" }, { status: 401 });
    }

    console.log('Fetching tasks for user:', session.user.email);
    const userId = await getLeantimeUserId(session.user.email);
    
    if (!userId) {
      console.error('User not found in Leantime:', session.user.email);
      return NextResponse.json({ error: "User not found in Leantime" }, { status: 404 });
    }

    console.log('Fetching tasks for Leantime user ID:', userId);
    const response = await fetch(`${process.env.LEANTIME_API_URL}/api/jsonrpc`, {
      method: 'POST',
      headers: {
        'Content-Type': 'application/json',
        'apiKey': process.env.LEANTIME_TOKEN
      },
      body: JSON.stringify({
        jsonrpc: '2.0',
        method: 'leantime.rpc.tickets.getAll',
        params: {
          userId: userId,
          status: "all"
        },
        id: 1
      }),
    });

    const responseText = await response.text();
    console.log('Raw tasks response:', responseText);

    if (!response.ok) {
      console.error('Failed to fetch tasks from Leantime:', {
        status: response.status,
        statusText: response.statusText,
        headers: Object.fromEntries(response.headers.entries())
      });
      throw new Error('Failed to fetch tasks from Leantime');
    }

    let data;
    try {
      data = JSON.parse(responseText);
    } catch (e) {
      console.error('Failed to parse tasks response:', e);
      throw new Error('Invalid response format from Leantime');
    }

    console.log('Leantime tasks response:', {
      success: true,
      taskCount: data.result?.length || 0
    });

    if (!data.result || !Array.isArray(data.result)) {
      console.error('Invalid response format from Leantime tasks API');
      throw new Error('Invalid response format from Leantime');
    }

    const tasks = data.result.map((task: any) => ({
      id: task.id.toString(),
      headline: task.headline,
      projectName: task.projectName,
      projectId: task.projectId,
      status: task.status,
      dueDate: task.dateToFinish || null,
      milestone: task.type || null,
      details: task.description || null,
      editTo: task.editTo || null,
      dependingTicketId: task.dependingTicketId || null
    }));

    // Sort tasks by due date
    tasks.sort((a: any, b: any) => {
      if (!a.dueDate) return 1;
      if (!b.dueDate) return -1;
      return new Date(a.dueDate).getTime() - new Date(b.dueDate).getTime();
    });

    return NextResponse.json({ tasks });
  } catch (error) {
    console.error('Error in tasks route:', error);
    return NextResponse.json(
      { error: "Failed to fetch tasks" },
      { status: 500 }
    );
  }
}