import { NextResponse } from "next/server";
import { readFileSync, writeFileSync, existsSync } from "fs";
import { join } from "path";

const DATA_FILE = join(process.cwd(), "data", "tasks.json");

interface Task {
  id: string;
  title: string;
  description?: string;
  type: 'idea' | 'task' | 'bug' | 'research' | 'plan';
  status: 'backlog' | 'in-progress' | 'review' | 'done' | 'archived';
  priority: 'low' | 'medium' | 'high' | 'urgent';
  projectId: string;
  sprintId?: string;
  createdAt: string;
  updatedAt: string;
  dueDate?: string;
  comments: { id: string; text: string; createdAt: string; author: 'user' | 'assistant' }[];
  tags: string[];
}

interface Project {
  id: string;
  name: string;
  description?: string;
  color: string;
  createdAt: string;
}

interface Sprint {
  id: string;
  name: string;
  goal?: string;
  startDate: string;
  endDate: string;
  status: 'planning' | 'active' | 'completed';
  projectId: string;
  createdAt: string;
}

interface DataStore {
  projects: Project[];
  tasks: Task[];
  sprints: Sprint[];
  lastUpdated: number;
}

const defaultData: DataStore = {
  projects: [
    { id: '1', name: 'OpenClaw iOS', description: 'Main iOS app development', color: '#8b5cf6', createdAt: new Date().toISOString() },
    { id: '2', name: 'Web Projects', description: 'Web tools and dashboards', color: '#3b82f6', createdAt: new Date().toISOString() },
    { id: '3', name: 'Research', description: 'Experiments and learning', color: '#10b981', createdAt: new Date().toISOString() },
  ],
  tasks: [],
  sprints: [],
  lastUpdated: Date.now(),
};

function getData(): DataStore {
  if (!existsSync(DATA_FILE)) {
    return defaultData;
  }
  try {
    const data = readFileSync(DATA_FILE, "utf-8");
    return JSON.parse(data);
  } catch {
    return defaultData;
  }
}

function saveData(data: DataStore) {
  const dir = join(process.cwd(), "data");
  if (!existsSync(dir)) {
    require("fs").mkdirSync(dir, { recursive: true });
  }
  data.lastUpdated = Date.now();
  writeFileSync(DATA_FILE, JSON.stringify(data, null, 2));
}

// GET - fetch all tasks, projects, and sprints
export async function GET() {
  const data = getData();
  return NextResponse.json(data);
}

// POST - create or update tasks, projects, or sprints
export async function POST(request: Request) {
  try {
    const { task, projects, sprints } = await request.json();
    const data = getData();

    // Update projects if provided
    if (projects) {
      data.projects = projects;
    }

    // Update sprints if provided
    if (sprints) {
      data.sprints = sprints;
    }

    // Update or add task
    if (task) {
      const existingIndex = data.tasks.findIndex((t) => t.id === task.id);
      if (existingIndex >= 0) {
        data.tasks[existingIndex] = { ...task, updatedAt: new Date().toISOString() };
      } else {
        data.tasks.push({
          ...task,
          id: task.id || Date.now().toString(),
          createdAt: new Date().toISOString(),
          updatedAt: new Date().toISOString(),
        });
      }
    }

    saveData(data);
    return NextResponse.json({ success: true, data });
  } catch (error) {
    return NextResponse.json({ error: "Failed to save" }, { status: 500 });
  }
}

// DELETE - remove a task
export async function DELETE(request: Request) {
  try {
    const { id } = await request.json();
    const data = getData();
    data.tasks = data.tasks.filter((t) => t.id !== id);
    saveData(data);
    return NextResponse.json({ success: true });
  } catch (error) {
    return NextResponse.json({ error: "Failed to delete" }, { status: 500 });
  }
}