"use client";

import { createContext, useContext, useState, useEffect, ReactNode } from "react";
import { Task, TaskStatus, initialTasks } from "./types";

interface MissionControlStore {
  tasks: Task[];
  toggleTask: (id: string) => void;
  updateTaskStatus: (id: string, status: TaskStatus) => void;
  addTask: (task: Omit<Task, "id" | "order">) => void;
  getProjectProgress: (projectId: string) => number;
  getTasksByProject: (projectId: string) => Task[];
}

const MissionControlContext = createContext<MissionControlStore | null>(null);

const STORAGE_KEY = "sitemente:mission-control";

export function MissionControlProvider({ children }: { children: ReactNode }) {
  const [tasks, setTasks] = useState<Task[]>(initialTasks);

  // Load from localStorage on mount
  useEffect(() => {
    if (typeof window === "undefined") return;
    const saved = localStorage.getItem(STORAGE_KEY);
    if (saved) {
      try {
        const parsed = JSON.parse(saved);
        if (Array.isArray(parsed) && parsed.length > 0) {
          setTasks(parsed);
        }
      } catch {
        // Use default
      }
    }
  }, []);

  // Save to localStorage on change
  useEffect(() => {
    if (typeof window === "undefined") return;
    localStorage.setItem(STORAGE_KEY, JSON.stringify(tasks));
  }, [tasks]);

  const toggleTask = (id: string) => {
    setTasks((prev) =>
      prev.map((t) => {
        if (t.id !== id) return t;
        const newStatus: TaskStatus = t.status === "done" ? "todo" : "done";
        return {
          ...t,
          status: newStatus,
          completedAt: newStatus === "done" ? new Date().toISOString().split("T")[0] : undefined,
        };
      })
    );
  };

  const updateTaskStatus = (id: string, status: TaskStatus) => {
    setTasks((prev) =>
      prev.map((t) =>
        t.id === id
          ? {
              ...t,
              status,
              completedAt: status === "done" ? new Date().toISOString().split("T")[0] : undefined,
            }
          : t
      )
    );
  };

  const addTask = (task: Omit<Task, "id" | "order">) => {
    const newTask: Task = {
      ...task,
      id: `t-${Date.now()}`,
      order: tasks.length + 1,
    };
    setTasks((prev) => [...prev, newTask]);
  };

  const getProjectProgress = (projectId: string) => {
    const projectTasks = tasks.filter((t) => t.project === projectId);
    if (projectTasks.length === 0) return 0;
    const done = projectTasks.filter((t) => t.status === "done").length;
    return Math.round((done / projectTasks.length) * 100);
  };

  const getTasksByProject = (projectId: string) => {
    return tasks.filter((t) => t.project === projectId).sort((a, b) => a.order - b.order);
  };

  return (
    <MissionControlContext.Provider
      value={{
        tasks,
        toggleTask,
        updateTaskStatus,
        addTask,
        getProjectProgress,
        getTasksByProject,
      }}
    >
      {children}
    </MissionControlContext.Provider>
  );
}

export function useMissionControl() {
  const ctx = useContext(MissionControlContext);
  if (!ctx) {
    throw new Error("useMissionControl must be used within MissionControlProvider");
  }
  return ctx;
}
