import { useState, useEffect } from "react";
import { SAMPLE_TASKS } from "../data/constants";

function getWeekDates() {
  const today = new Date();
  const day = today.getDay();
  const monday = new Date(today);
  monday.setDate(today.getDate() - ((day + 6) % 7));
  return Array.from({ length: 5 }, (_, i) => {
    const d = new Date(monday);
    d.setDate(monday.getDate() + i);
    return d;
  });
}

// Assign default due dates spread across the week for sample tasks
function seedTasks() {
  const week = getWeekDates();
  return {
    abdulla: SAMPLE_TASKS.abdulla.map((t, i) => ({
      ...t,
      due: week[i + 1]?.toISOString().split("T")[0] || week[2].toISOString().split("T")[0],
    })),
    salama: SAMPLE_TASKS.salama.map((t, i) => ({
      ...t,
      due: week[i]?.toISOString().split("T")[0] || week[0].toISOString().split("T")[0],
    })),
  };
}

export function useTasks() {
  const [tasks, setTasks] = useState(() => {
    try {
      const saved = localStorage.getItem("ascs_tasks");
      return saved ? JSON.parse(saved) : seedTasks();
    } catch {
      return seedTasks();
    }
  });

  useEffect(() => {
    localStorage.setItem("ascs_tasks", JSON.stringify(tasks));
  }, [tasks]);

  function addTask(kidId, task) {
    setTasks((prev) => ({
      ...prev,
      [kidId]: [...prev[kidId], { ...task, id: Date.now() }],
    }));
  }

  function updateStatus(kidId, taskId, status) {
    setTasks((prev) => ({
      ...prev,
      [kidId]: prev[kidId].map((t) => (t.id === taskId ? { ...t, status } : t)),
    }));
  }

  function removeTask(kidId, taskId) {
    setTasks((prev) => ({
      ...prev,
      [kidId]: prev[kidId].filter((t) => t.id !== taskId),
    }));
  }

  return { tasks, addTask, updateStatus, removeTask };
}