// state.js
import { LOCAL_STORAGE_KEY, DEFAULT_PLAYERS, GAME_STATES, DEFAULT_PLAYER_TIME_SECONDS } from '../config.js';

let players = [];
let currentPlayerIndex = 0;
let gameState = GAME_STATES.SETUP;

// --- State Accessors ---

export function getPlayers() {
    return [...players]; // Return a copy to prevent direct mutation
}

export function getCurrentPlayer() {
    if (players.length === 0) return null;
    return players[currentPlayerIndex];
}

export function getPlayerById(id) {
    return players.find(p => p.id === id);
}

export function getCurrentPlayerIndex() {
    return currentPlayerIndex;
}

export function getGameState() {
    return gameState;
}

// --- State Mutators ---

export function setPlayers(newPlayers) {
    players = newPlayers;
    saveData();
}

export function setCurrentPlayerIndex(index) {
    if (index >= 0 && index < players.length) {
        currentPlayerIndex = index;
        saveData();
    } else {
        console.error(`Invalid player index: ${index}`);
    }
}

export function setGameState(newState) {
    if (Object.values(GAME_STATES).includes(newState)) {
        gameState = newState;
        saveData();
    } else {
        console.error(`Invalid game state: ${newState}`);
    }
}

export function updatePlayerTime(index, remainingTime) {
    if (index >= 0 && index < players.length) {
        players[index].remainingTime = Math.max(0, remainingTime); // Ensure time doesn't go below 0
        saveData(); // Save data whenever time updates
    }
}

export function addPlayer(name, timeInMinutes, image = null) {
    const timeInSeconds = timeInMinutes * 60;
    const newId = Date.now();
    players.push({
        id: newId,
        name: name,
        timeInSeconds: timeInSeconds,
        remainingTime: timeInSeconds,
        image: image
    });
    currentPlayerIndex = players.length - 1; // Focus new player
    saveData();
    return players[players.length - 1]; // Return the newly added player
}

export function updatePlayer(index, name, timeInMinutes, remainingTimeSeconds, image) {
     if (index >= 0 && index < players.length) {
        const player = players[index];
        const timeInSeconds = timeInMinutes * 60;

        player.name = name;
        player.timeInSeconds = timeInSeconds;

        // Update remaining time carefully based on game state
        if (gameState === GAME_STATES.SETUP) {
            player.remainingTime = timeInSeconds;
        } else if (gameState === GAME_STATES.PAUSED || gameState === GAME_STATES.OVER) {
            // Allow direct setting of remaining time only when paused or over
             player.remainingTime = remainingTimeSeconds;
        }
        // If running, remaining time is managed by the timer, don't override here unless intended

        if (image !== undefined) { // Allow updating image (null means remove image)
            player.image = image;
        }
        saveData();
        return player;
     }
     return null;
}

export function deletePlayer(index) {
    if (players.length <= 2) {
        console.warn('Cannot delete player, minimum 2 players required.');
        return false; // Indicate deletion failed
    }
    if (index >= 0 && index < players.length) {
        players.splice(index, 1);
        if (currentPlayerIndex >= players.length) {
            currentPlayerIndex = players.length - 1;
        } else if (currentPlayerIndex > index) {
             // Adjust index if deleting someone before the current player
            // No adjustment needed if deleting current or after current
        }
        saveData();
        return true; // Indicate success
    }
    return false; // Indicate deletion failed
}

export function resetPlayersTime() {
    players.forEach(player => {
        player.remainingTime = player.timeInSeconds;
    });
    saveData();
}

export function resetToDefaults() {
    // Deep copy default players to avoid modifying the constant
    players = JSON.parse(JSON.stringify(DEFAULT_PLAYERS));
    gameState = GAME_STATES.SETUP;
    currentPlayerIndex = 0;
    saveData();
}

export function areAllTimersFinished() {
    return players.every(player => player.remainingTime <= 0);
}

// Returns the index of the next player with time > 0, or -1 if none
export function findNextPlayerWithTime() {
    if (players.length === 0) return -1;
    const startIndex = (currentPlayerIndex + 1) % players.length;
    let index = startIndex;

    do {
        if (players[index].remainingTime > 0) {
            return index;
        }
        index = (index + 1) % players.length;
    } while (index !== startIndex);

    // Check current player last if no others found
    if(players[currentPlayerIndex].remainingTime > 0) {
        return currentPlayerIndex;
    }

    return -1; // No player has time left
}

// Find next player with time in specified direction (1 for next, -1 for prev)
export function findNextPlayerWithTimeCircular(direction) {
    if (players.length === 0) return -1;
    let index = currentPlayerIndex;

    for (let i = 0; i < players.length; i++) {
        index = (index + direction + players.length) % players.length;
        if (players[index]?.remainingTime > 0) { // Check if player exists and has time
            return index;
        }
    }

    // If no other player found, check if current player has time (only relevant if direction search fails)
    if (players[currentPlayerIndex]?.remainingTime > 0) {
        return currentPlayerIndex;
    }

    return -1; // No player has time left
}


// --- Persistence ---

export function saveData() {
    const dataToSave = {
        players,
        gameState,
        currentPlayerIndex
    };
    try {
        localStorage.setItem(LOCAL_STORAGE_KEY, JSON.stringify(dataToSave));
    } catch (error) {
        console.error("Error saving data to localStorage:", error);
        // Maybe notify the user that settings won't be saved
    }
}

export function loadData() {
    const savedData = localStorage.getItem(LOCAL_STORAGE_KEY);
    if (savedData) {
        try {
            const parsedData = JSON.parse(savedData);
            players = parsedData.players || JSON.parse(JSON.stringify(DEFAULT_PLAYERS));
            gameState = parsedData.gameState || GAME_STATES.SETUP;
            currentPlayerIndex = parsedData.currentPlayerIndex || 0;

            // Basic validation/migration if needed
            if (currentPlayerIndex >= players.length) {
                currentPlayerIndex = 0;
            }
             // Ensure all players have necessary properties
            players = players.map(p => ({
                id: p.id || Date.now() + Math.random(), // Ensure ID exists
                name: p.name || 'Player',
                timeInSeconds: p.timeInSeconds || DEFAULT_PLAYER_TIME_SECONDS,
                remainingTime: p.remainingTime !== undefined ? p.remainingTime : (p.timeInSeconds || DEFAULT_PLAYER_TIME_SECONDS),
                image: p.image || null
            }));

        } catch (error) {
            console.error("Error parsing data from localStorage:", error);
            resetToDefaults(); // Reset to defaults if stored data is corrupt
        }
    } else {
        resetToDefaults(); // Use defaults if no saved data
    }
    // No saveData() here, loadData just loads the state
}