// ✅ src/pages/TaskPage.js
import React, { useEffect, useState, useCallback } from "react";
import TodoForm from "../components/Todo/TodoForm";
import TodoList from "../components/Todo/TodoList";
import TodoDetail from "../components/Todo/TodoDetail";
import todoApi from "../api/todoApi";

const FILTERS = [
  { label: "오늘 할 일", value: "today" },
  { label: "중요", value: "important" },
  { label: "계획된 일정", value: "scheduled" },
  { label: "전체", value: "all" },
  { label: "완료된 작업", value: "completed" }, // ✅ 추가됨
];

const TaskPage = () => {
  const [tasks, setTasks] = useState([]);
  const [selectedFilter, setSelectedFilter] = useState("all");
  const [selectedTag, setSelectedTag] = useState(null);
  const [selectedTask, setSelectedTask] = useState(null);

  const fetchTasks = useCallback(async () => {
    try {
      const res = await todoApi.get("/api/todo/tasks/");
      setTasks(res.data);
    } catch (err) {
      console.error("목록 불러오기 실패:", err);
    }
  }, []);

  useEffect(() => {
    fetchTasks();
  }, [fetchTasks]);

  const closeDetail = () => setSelectedTask(null);

  const filteredTasks = tasks.filter((task) => {
    if (selectedTag) return task.tags?.includes(selectedTag);
    if (selectedFilter === "today") {
      const today = new Date().toISOString().split("T")[0];
      return task.due_date === today;
    } else if (selectedFilter === "important") {
      return task.tags?.includes("중요");
    } else if (selectedFilter === "scheduled") {
      return !!task.due_date;
    } else if (selectedFilter === "completed") {
      return task.is_completed;
    }
    return true; // 전체
  });

  const allTags = [...new Set(tasks.flatMap((task) => task.tags || []))];

  const toggleComplete = async (taskId, is_completed) => {
    try {
      await todoApi.patch(`/api/todo/tasks/${taskId}/`, {
        is_completed: !is_completed,
      });
      fetchTasks();
    } catch (err) {
      console.error("완료 상태 변경 실패:", err);
    }
  };

  const deleteTask = async (taskId) => {
    if (!window.confirm("정말로 이 작업을 삭제하시겠습니까?")) return;

    try {
      await todoApi.delete(`/api/todo/tasks/${taskId}/`);
      if (selectedTask?.id === taskId) setSelectedTask(null);
      fetchTasks();
    } catch (err) {
      console.error("삭제 실패:", err);
      alert("삭제에 실패했습니다.");
    }
  };

  return (
    <div className="flex h-screen bg-gray-50">
      {/* ✅ 왼쪽 사이드바 - 목록 + 태그 */}
      <aside className="w-60 border-r border-gray-200 p-4 space-y-4 bg-white overflow-y-auto">
        <div>
          <h2 className="text-lg font-bold mb-2">📂 목록</h2>
          {FILTERS.map((filter) => (
            <button
              key={filter.value}
              onClick={() => {
                setSelectedFilter(filter.value);
                setSelectedTag(null);
              }}
              className={`w-full text-left px-2 py-1 rounded hover:bg-gray-100 ${
                selectedFilter === filter.value && !selectedTag
                  ? "bg-blue-100 font-semibold"
                  : ""
              }`}
            >
              {filter.label}
            </button>
          ))}
        </div>

        <div>
          <h2 className="text-md font-semibold mt-6 mb-2">🏷 태그</h2>
          {allTags.map((tag) => (
            <button
              key={tag}
              onClick={() => {
                setSelectedTag(tag);
                setSelectedFilter(null);
              }}
              className={`w-full text-left px-2 py-1 rounded hover:bg-gray-100 ${
                selectedTag === tag ? "bg-blue-100 font-semibold" : ""
              }`}
            >
              #{tag}
            </button>
          ))}
        </div>
      </aside>

      {/* 가운데 메인 영역 */}
      <main className="flex-1 border-r border-gray-200 p-4 overflow-y-auto">
        <TodoForm onTaskCreated={fetchTasks} />
        <div className="flex justify-between items-center mb-4">
          <h2 className="text-xl font-bold">
            📋{" "}
            {(selectedTag && `태그: ${selectedTag}`) ||
              FILTERS.find((f) => f.value === selectedFilter)?.label ||
              "할 일"}
          </h2>
        </div>

        <TodoList
          tasks={filteredTasks}
          onSelectTask={setSelectedTask}
          onToggleComplete={toggleComplete}
          onTagClick={(tag) => {
            setSelectedTag(tag);
            setSelectedFilter(null);
          }}
          onDelete={deleteTask}
        />
      </main>

      {/* 오른쪽 상세 Drawer */}
      <section
        className={`fixed top-0 right-0 h-full w-full md:w-1/2 lg:w-2/5 xl:w-1/3 bg-white shadow-lg border-l border-gray-300 transform transition-transform duration-300 ease-in-out z-50 ${
          selectedTask ? "translate-x-0" : "translate-x-full"
        }`}
      >
        <button
          onClick={closeDetail}
          className="absolute top-4 right-4 text-gray-600 hover:text-red-500 text-2xl font-bold"
        >
          &times;
        </button>
        {selectedTask && (
          <div className="p-6">
            <TodoDetail
              task={selectedTask}
              onUpdated={() => {
                fetchTasks(); // 목록 갱신
                setSelectedTask(null); // 상세 창 닫기 (필요에 따라 유지 가능)
              }}
            />
          </div>
        )}
      </section>

      {selectedTask && (
        <div
          className="fixed inset-0 bg-black bg-opacity-30 z-40"
          onClick={closeDetail}
        />
      )}
    </div>
  );
};

export default TaskPage;