/***********************************************************************************************************************************************************************
 * File Name: StaffTaskContext.jsx
 * Type of Program: Context
 * Description: Staff task management context — aligned to the updated tasks.ctrl.js.
 *              Supports pagination, archive/restore, bulk ops, and filter field values
 *              to match the DataTable-based TaskListsPage.
 ***********************************************************************************************************************************************************************/
import { createContext, useContext, useState, useCallback } from "react";
import api from "@/utils/api.util";
import { toast } from "sonner";

const StaffTaskContext = createContext(null);

export const useStaffTasks = () => {
  const ctx = useContext(StaffTaskContext);
  if (!ctx) throw new Error("useStaffTasks must be used inside StaffTaskProvider");
  return ctx;
};

const BASE = "/staff";

const PAGINATION_INIT = {
  page: 1,
  limit: 10,
  totalRecords: 0,
  totalPages: 0,
  hasPrevPage: false,
  hasNextPage: false,
};

export const StaffTaskProvider = ({ children }) => {
  // ── Task Lists ──────────────────────────────────────────────────────────────
  const [taskLists,   setTaskLists]   = useState([]);
  const [taskList,    setTaskList]    = useState(null);
  const [attributes,  setAttributes]  = useState([]);
  const [pagination,  setPagination]  = useState(PAGINATION_INIT);

  // ── Tasks ───────────────────────────────────────────────────────────────────
  const [tasks,       setTasks]       = useState([]);
  const [task,        setTask]        = useState(null);
  const [taskAttrs,   setTaskAttrs]   = useState([]);
  const [taskPagination, setTaskPagination] = useState(PAGINATION_INIT);

  const [loading,     setLoading]     = useState(false);
  const [error,       setError]       = useState(null);

  // ── Internal request wrapper ────────────────────────────────────────────────
  const request = useCallback(async (fn) => {
    setLoading(true);
    setError(null);
    try {
      return await fn();
    } catch (err) {
      const message = err?.response?.data?.message || err.message || "Something went wrong.";
      setError(message);
      toast.error(message);
      return null;
    } finally {
      setLoading(false);
    }
  }, []);

  // ── Build query params from DataTable fetch args ────────────────────────────
  const buildParams = ({ page, limit, filters, sort, archived } = {}) => ({
    ...(page    && { page }),
    ...(limit   && { limit }),
    ...(archived !== undefined && { archived }),
    ...(filters?.length && { filters: JSON.stringify(filters) }),
    ...(sort?.length    && { sort:    JSON.stringify(sort) }),
  });

  // ════════════════════════════════════════════════════════════════════════════
  // TASK LISTS
  // ════════════════════════════════════════════════════════════════════════════

  // ─── GET /staff/task-lists ───────────────────────────────────────────────
  const fetchTaskLists = useCallback(
    (args = {}) =>
      request(async () => {
        const res = await api.get(`${BASE}/task-lists`, { params: buildParams(args) });
        const { data, attributes, pagination } = res.data?.data;
        
        setTaskLists(data ?? []);
        setAttributes(attributes ?? []);
        setPagination(pagination  ?? null);

        return res.data;
      }),
    [request]
  );

  // ─── GET /staff/task-lists/archived ──────────────────────────────────────
  const fetchArchivedTaskLists = useCallback(
    (args = {}) =>
      request(async () => {
        const res = await api.get(`${BASE}/task-lists/archived`, { params: buildParams(args) });
        const payload = res.data?.data;
        setTaskLists(payload?.rows   ?? payload ?? []);
        setAttributes(payload?.attributes ?? []);
        setPagination(payload?.pagination  ?? null);
        return res.data;
      }),
    [request]
  );

  // ─── GET /staff/task-lists/field-values ──────────────────────────────────
  const fetchTaskListFieldValues = useCallback(
    (field, args = {}) =>
      request(async () => {
        const res = await api.get(`${BASE}/task-lists/field-values`, {
          params: { field, ...buildParams(args) },
        });
        return res.data;
      }),
    [request]
  );

  // ─── GET /staff/task-lists/:taskListId ───────────────────────────────────
  const fetchTaskList = useCallback(
    (taskListId) =>
      request(async () => {
        const res = await api.get(`${BASE}/task-lists/${taskListId}`);
        setTaskList(res.data?.data ?? null);
        return res.data;
      }),
    [request]
  );

  // ─── POST /staff/task-lists ──────────────────────────────────────────────
  // body: { name, description, group_ids: ["27", "28"] }
  const addTaskList = useCallback(
    (payload) =>
      request(async () => {
        const res = await api.post(`${BASE}/task-lists`, payload);
        const created = res.data?.data;
        if (created) setTaskLists((prev) => [created, ...prev]);
        toast.success("Task list created.");
        return res.data;
      }),
    [request]
  );

  // ─── PUT /staff/task-lists/:taskListId ───────────────────────────────────
  const updateTaskList = useCallback(
    (taskListId, payload) =>
      request(async () => {
        const res = await api.put(`${BASE}/task-lists/${taskListId}`, payload);
        const updated = res.data?.data;
        if (updated) {
          setTaskLists((prev) =>
            prev.map((tl) => (tl.task_list_id === taskListId ? { ...tl, ...updated } : tl))
          );
          if (taskList?.task_list_id === taskListId)
            setTaskList((prev) => ({ ...prev, ...updated }));
        }
        toast.success("Task list updated.");
        return res.data;
      }),
    [request, taskList]
  );

  // ─── POST /staff/task-lists/:taskListId/archive ──────────────────────────
  const archiveTaskList = useCallback(
    (taskListId) =>
      request(async () => {
        const res = await api.post(`${BASE}/task-lists/${taskListId}/archive`);
        setTaskLists((prev) => prev.filter((tl) => tl.task_list_id !== taskListId));
        if (taskList?.task_list_id === taskListId) setTaskList(null);
        toast.success("Task list archived.");
        return res.data;
      }),
    [request, taskList]
  );

  // ─── POST /staff/task-lists/:taskListId/restore ──────────────────────────
  const restoreTaskList = useCallback(
    (taskListId) =>
      request(async () => {
        const res = await api.post(`${BASE}/task-lists/${taskListId}/restore`);
        setTaskLists((prev) => prev.filter((tl) => tl.task_list_id !== taskListId));
        toast.success("Task list restored.");
        return res.data;
      }),
    [request]
  );

  // ─── POST /staff/task-lists/bulk-archive ─────────────────────────────────
  const bulkArchiveTaskLists = useCallback(
    (ids) =>
      request(async () => {
        const res = await api.post(`${BASE}/task-lists/bulk-archive`, { ids });
        const { archived_ids = [] } = res.data?.data ?? {};
        setTaskLists((prev) =>
          prev.filter((tl) => !archived_ids.includes(tl.task_list_id))
        );
        toast.success(`${archived_ids.length} task list(s) archived.`);
        return res.data;
      }),
    [request]
  );

  // ─── POST /staff/task-lists/bulk-restore ─────────────────────────────────
  const bulkRestoreTaskLists = useCallback(
    (ids) =>
      request(async () => {
        const res = await api.post(`${BASE}/task-lists/bulk-restore`, { ids });
        const { restored_ids = [] } = res.data?.data ?? {};
        setTaskLists((prev) =>
          prev.filter((tl) => !restored_ids.includes(tl.task_list_id))
        );
        toast.success(`${restored_ids.length} task list(s) restored.`);
        return res.data;
      }),
    [request]
  );

  // ════════════════════════════════════════════════════════════════════════════
  // TASKS
  // ════════════════════════════════════════════════════════════════════════════

  // ─── GET /staff/task-lists/:taskListId/tasks ─────────────────────────────
  const fetchTasks = useCallback(
    (taskListId, args = {}) =>
      request(async () => {
        const res = await api.get(`${BASE}/task-lists/${taskListId}/tasks`, {
          params: buildParams(args),
        });
        const payload = res.data?.data;
        setTasks(payload?.rows        ?? payload ?? []);
        setTaskAttrs(payload?.attributes  ?? []);
        setTaskPagination(payload?.pagination ?? null);
        return res.data;
      }),
    [request]
  );

  // ─── GET /staff/task-lists/:taskListId/tasks/archived ────────────────────
  const fetchArchivedTasks = useCallback(
    (taskListId, args = {}) =>
      request(async () => {
        const res = await api.get(`${BASE}/task-lists/${taskListId}/tasks/archived`, {
          params: buildParams(args),
        });
        const payload = res.data?.data;
        setTasks(payload?.rows        ?? payload ?? []);
        setTaskAttrs(payload?.attributes  ?? []);
        setTaskPagination(payload?.pagination ?? null);
        return res.data;
      }),
    [request]
  );

  // ─── GET /staff/task-lists/:taskListId/tasks/field-values ────────────────
  const fetchTaskFieldValues = useCallback(
    (taskListId, field, args = {}) =>
      request(async () => {
        const res = await api.get(`${BASE}/task-lists/${taskListId}/tasks/field-values`, {
          params: { field, ...buildParams(args) },
        });
        return res.data;
      }),
    [request]
  );

  // ─── GET /staff/task-lists/:taskListId/tasks/:taskId ─────────────────────
  const fetchTask = useCallback(
    (taskListId, taskId) =>
      request(async () => {
        const res = await api.get(`${BASE}/task-lists/${taskListId}/tasks/${taskId}`);
        setTask(res.data?.data ?? null);
        return res.data;
      }),
    [request]
  );

  // ─── POST /staff/task-lists/:taskListId/tasks ────────────────────────────
  // body: { name, description, deadline, requirements: [{ type, ...fields }] }
  const addTask = useCallback(
    (taskListId, payload) =>
      request(async () => {
        const res = await api.post(`${BASE}/task-lists/${taskListId}/tasks`, payload);
        const created = res.data?.data;
        if (created) {
          setTasks((prev) => [...prev, created]);
          setTaskLists((prev) =>
            prev.map((tl) =>
              tl.task_list_id === taskListId
                ? { ...tl, tasks: [...(tl.tasks ?? []), created] }
                : tl
            )
          );
        }
        toast.success("Task created.");
        return res.data;
      }),
    [request]
  );

  // ─── PUT /staff/task-lists/:taskListId/tasks/:taskId ─────────────────────
  const updateTask = useCallback(
    (taskListId, taskId, payload) =>
      request(async () => {
        const res = await api.put(`${BASE}/task-lists/${taskListId}/tasks/${taskId}`, payload);
        const updated = res.data?.data;
        if (updated) {
          setTasks((prev) =>
            prev.map((t) => (t.task_id === taskId ? { ...t, ...updated } : t))
          );
          setTaskLists((prev) =>
            prev.map((tl) =>
              tl.task_list_id === taskListId
                ? {
                    ...tl,
                    tasks: tl.tasks?.map((t) =>
                      t.task_id === taskId ? { ...t, ...updated } : t
                    ),
                  }
                : tl
            )
          );
          if (task?.task_id === taskId) setTask((prev) => ({ ...prev, ...updated }));
        }
        toast.success("Task updated.");
        return res.data;
      }),
    [request, task]
  );

  // ─── POST /staff/task-lists/:taskListId/tasks/:taskId/archive ────────────
  const archiveTask = useCallback(
    (taskListId, taskId) =>
      request(async () => {
        const res = await api.post(`${BASE}/task-lists/${taskListId}/tasks/${taskId}/archive`);
        setTasks((prev) => prev.filter((t) => t.task_id !== taskId));
        setTaskLists((prev) =>
          prev.map((tl) =>
            tl.task_list_id === taskListId
              ? { ...tl, tasks: tl.tasks?.filter((t) => t.task_id !== taskId) }
              : tl
          )
        );
        toast.success("Task archived.");
        return res.data;
      }),
    [request]
  );

  // ─── POST /staff/task-lists/:taskListId/tasks/:taskId/restore ────────────
  const restoreTask = useCallback(
    (taskListId, taskId) =>
      request(async () => {
        const res = await api.post(`${BASE}/task-lists/${taskListId}/tasks/${taskId}/restore`);
        setTasks((prev) => prev.filter((t) => t.task_id !== taskId));
        toast.success("Task restored.");
        return res.data;
      }),
    [request]
  );

  // ─── POST /staff/task-lists/:taskListId/tasks/bulk-archive ───────────────
  const bulkArchiveTasks = useCallback(
    (taskListId, ids) =>
      request(async () => {
        const res = await api.post(`${BASE}/task-lists/${taskListId}/tasks/bulk-archive`, { ids });
        const { archived_ids = [] } = res.data?.data ?? {};
        setTasks((prev) => prev.filter((t) => !archived_ids.includes(t.task_id)));
        toast.success(`${archived_ids.length} task(s) archived.`);
        return res.data;
      }),
    [request]
  );

  // ─── POST /staff/task-lists/:taskListId/tasks/bulk-restore ───────────────
  const bulkRestoreTasks = useCallback(
    (taskListId, ids) =>
      request(async () => {
        const res = await api.post(`${BASE}/task-lists/${taskListId}/tasks/bulk-restore`, { ids });
        const { restored_ids = [] } = res.data?.data ?? {};
        setTasks((prev) => prev.filter((t) => !restored_ids.includes(t.task_id)));
        toast.success(`${restored_ids.length} task(s) restored.`);
        return res.data;
      }),
    [request]
  );

  return (
    <StaffTaskContext.Provider
      value={{
        // ── Task List state
        taskLists, taskList, attributes, pagination, 
        setPagination, setTaskList,

        // ── Task List actions
        fetchTaskLists, fetchArchivedTaskLists, fetchTaskListFieldValues,
        fetchTaskList,
        addTaskList, updateTaskList,
        archiveTaskList, restoreTaskList,
        bulkArchiveTaskLists, bulkRestoreTaskLists,

        // ── Task state
        tasks, task, taskAttrs, taskPagination,
        setTask,

        // ── Task actions
        fetchTasks, fetchArchivedTasks, fetchTaskFieldValues,
        fetchTask,
        addTask, updateTask,
        archiveTask, restoreTask,
        bulkArchiveTasks, bulkRestoreTasks,

        // ── Shared
        loading, error,
      }}
    >
      {children}
    </StaffTaskContext.Provider>
  );
};