import { useState, useEffect, useRef } from "react";
// Usage
function App() {
  // State value and setter for our example
  const [count, setCount] = useState(0);
  // Get the previous value (was passed into hook on last render)
  const prevCount = usePrevious(count);
  // Display both current and previous count value
  return (
    <div>
      <h1>
        Now: {count}, before: {prevCount}
      </h1>
      <button onClick={() => setCount(count + 1)}>Increment</button>
    </div>
  );
}
// Hook
function usePrevious(value) {
  // The ref object is a generic container whose current property is mutable ...
  // ... and can hold any value, similar to an instance property on a class
  const ref = useRef();
  // Store current value in ref
  useEffect(() => {
    ref.current = value;
  }, [value]); // Only re-run if value changes
  // Return previous value (happens before update in useEffect above)
  return ref.current;
}

interface Task {
  id: number;
  title: string;
  completed: boolean;
}

class TaskManager {
  private tasks: Task[] = [];

  constructor() {}

  addTask(title: string) {
    const taskId = this.tasks.length + 1;
    const task: Task = {
      id: taskId,
      title,
      completed: false,
    };
    this.tasks.push(task);
  }

  markTaskAsComplete(taskId: number) {
    const task = this.tasks.find((task) => task.id === taskId);
    if (task) {
      task.completed = true;
    }
  }

  markTaskAsIncomplete(taskId: number) {
    const task = this.tasks.find((task) => task.id === taskId);
    if (task) {
      task.completed = false;
    }
  }

  listTasks() {
    console.log('Tasks:');
    this.tasks.forEach((task) => {
      console.log(`${task.id}. [${task.completed ? 'X' : ' '}] ${task.title}`);
    });
  }
}

// Example usage:
const taskManager = new TaskManager();
taskManager.addTask('Buy groceries');
taskManager.addTask('Pay bills');
taskManager.addTask('Clean the house');
taskManager.listTasks();

// Output:
// Tasks:
// 1. [ ] Buy groceries
// 2. [ ] Pay bills
// 3. [ ] Clean the house

// Print Hello, World!
console.log("Hello, World!");

const langToConfig = {
    'javascript': {
        image: '',
        cmd: ['']
    },
    'php': {
        image: '',
        cmd: ['']
    },
}

function twoSum(nums: number[], target: number): number[] {
    const map = new Map();
    for(let i = 0; i < nums.length; i++) {
        if(map.has(target - nums[i])) {
            return [map.get(target - nums[i]), i];
        } else {
            map.set(nums[i], i);
        }
    }
    return []
}

console.log(twoSum([1, 2, 3, 4, 5], 3))

function binarySearch(nums: number[], target: number): number {
    let left = 0;
    let right = nums.length - 1;

    while (left <= right) {
        const mid = left + Math.floor((right - left) / 2);

        if (nums[mid] === target) {
            return mid;
        } else if (nums[mid] < target) {
            left = mid + 1;
        } else {
            right = mid - 1;
        }
    }

    return left;
}

function searchInsert(nums: number[], target: number): number {
    return binarySearch(nums, target);
};