/**
 * This file is part of the SplendidBear Websites' projects.
 *
 * Copyright (c) 2026 @ www.splendidbear.org
 *
 * For the full copyright and license information, please view the LICENSE
 * file that was distributed with this source code.
 */

import React, { useEffect, useRef, useState } from 'react';
import { useGame } from '@mine-contexts';

const GameTimer = () => {
  const { overlay, connectionLost, endRef, activePlayer, webPlayer } = useGame();
  const [redTime, setRedTime] = useState(0);
  const [blueTime, setBlueTime] = useState(0);
  const [isRunning, setIsRunning] = useState(false);
  const timerIntervalRef = useRef(null);
  const gameStartedRef = useRef(false);

  // Use timestamps instead of counters for more reliable background tracking
  const redStartTimeRef = useRef(null);
  const blueStartTimeRef = useRef(null);
  const lastActivePlayerRef = useRef(null);
  const pausedRedTimeRef = useRef(0);
  const pausedBlueTimeRef = useRef(0);

  // Start timer when overlay is hidden (both players connected and game started)
  useEffect(() => {
    if (!overlay && !gameStartedRef.current) {
      gameStartedRef.current = true;
      setIsRunning(true);
      setRedTime(0);
      setBlueTime(0);
      redStartTimeRef.current = Date.now();
      blueStartTimeRef.current = Date.now();
      pausedRedTimeRef.current = 0;
      pausedBlueTimeRef.current = 0;
      lastActivePlayerRef.current = activePlayer;
    }
  }, [overlay]);

  // Stop timer on game end (resign/win)
  useEffect(() => {
    if (endRef.current) {
      setIsRunning(false);
    }
  }, [endRef.current]);

  // Stop timer on connection loss
  useEffect(() => {
    if (connectionLost) {
      setIsRunning(false);
    }
  }, [connectionLost]);

  // Handle player switch - pause one timer, resume the other
  useEffect(() => {
    if (!isRunning) return;

    if (lastActivePlayerRef.current !== activePlayer) {
      // Player switched, save current accumulated time for whoever was active
      const startRef = lastActivePlayerRef.current ? blueStartTimeRef.current : redStartTimeRef.current;
      if (startRef) {
        const elapsed = Math.floor((Date.now() - startRef) / 1000);
        if (lastActivePlayerRef.current) {
          pausedBlueTimeRef.current += elapsed;
        } else {
          pausedRedTimeRef.current += elapsed;
        }
      }

      // Start the new active player's timer
      if (activePlayer) {
        blueStartTimeRef.current = Date.now();
      } else {
        redStartTimeRef.current = Date.now();
      }

      lastActivePlayerRef.current = activePlayer;
    }
  }, [activePlayer, isRunning]);

  // Main timer effect - update display every 100ms
  useEffect(() => {
    if (!isRunning) {
      if (timerIntervalRef.current) {
        clearInterval(timerIntervalRef.current);
      }
      return;
    }

    timerIntervalRef.current = setInterval(() => {
      let currentRedTime = pausedRedTimeRef.current;
      let currentBlueTime = pausedBlueTimeRef.current;

      // Add elapsed time for the active player
      if (!activePlayer && redStartTimeRef.current) {
        currentRedTime += Math.floor((Date.now() - redStartTimeRef.current) / 1000);
      } else if (activePlayer && blueStartTimeRef.current) {
        currentBlueTime += Math.floor((Date.now() - blueStartTimeRef.current) / 1000);
      }

      setRedTime(currentRedTime);
      setBlueTime(currentBlueTime);
    }, 100);

    return () => {
      if (timerIntervalRef.current) {
        clearInterval(timerIntervalRef.current);
      }
    };
  }, [isRunning, activePlayer]);

  // Handle focus/blur to synchronize timer when tab regains focus
  useEffect(() => {
    const handleFocus = () => {
      // Force update when tab regains focus to sync any background drift
      if (isRunning) {
        let currentRedTime = pausedRedTimeRef.current;
        let currentBlueTime = pausedBlueTimeRef.current;

        if (!activePlayer && redStartTimeRef.current) {
          currentRedTime += Math.floor((Date.now() - redStartTimeRef.current) / 1000);
        } else if (activePlayer && blueStartTimeRef.current) {
          currentBlueTime += Math.floor((Date.now() - blueStartTimeRef.current) / 1000);
        }

        setRedTime(currentRedTime);
        setBlueTime(currentBlueTime);
      }
    };

    window.addEventListener('focus', handleFocus);
    return () => window.removeEventListener('focus', handleFocus);
  }, [isRunning, activePlayer]);

  // Cleanup on unmount
  useEffect(() => () => {
    if (timerIntervalRef.current) {
      clearInterval(timerIntervalRef.current);
    }
  }, []);

  const formatTime = seconds => {
    const mins = Math.floor(seconds / 60);
    const secs = seconds % 60;
    return `${String(mins).padStart(2, '0')}:${String(secs).padStart(2, '0')}`;
  };

  return (
    <div className="game-timer-container">
      <div className={`game-timer red-timer ${!activePlayer ? 'active' : ''}`}>
        <i className={`fa ${!activePlayer ? 'fa-hourglass-half' : 'fa-hourglass-start'} timer-icon`} />
        <span className="timer-display">{formatTime(redTime)}</span>
      </div>
      <div className={`game-timer blue-timer ${activePlayer ? 'active' : ''}`}>
        <i className={`fa ${activePlayer ? 'fa-hourglass-half' : 'fa-hourglass-start'} timer-icon`} />
        <span className="timer-display">{formatTime(blueTime)}</span>
      </div>
    </div>
  );
};

export default GameTimer;