// static/js/state.js

export let chatSessions = [];
export let activeChatId = null;
export let attachedFile = null;
export let isGenerating = false;
export let globalAbortController = null;
export let currentUploadXHR = null; // این متغیر دیگر برای آپلود استفاده نمی‌شود اما برای لغو پردازش فایل نگه داشته می‌شود
export let activeToolPrefix = null;
export let activeTool = null;

// *** START: ADDED FOR MESSAGE LIMIT ***
const DAILY_MESSAGE_LIMIT = 10;
const MESSAGE_LIMIT_KEY = 'alphaChatDailyLimit';

/**
 * Gets the current date as a formatted string (YYYY-MM-DD).
 * @returns {string} The formatted date string.
 */
function getTodayDateString() {
    const today = new Date();
    const year = today.getFullYear();
    const month = String(today.getMonth() + 1).padStart(2, '0');
    const day = String(today.getDate()).padStart(2, '0');
    return `${year}-${month}-${day}`;
}

/**
 * Retrieves usage data from localStorage.
 * @returns {{count: number, date: string}} The usage data object.
 */
function getUsageData() {
    try {
        const saved = localStorage.getItem(MESSAGE_LIMIT_KEY);
        return saved ? JSON.parse(saved) : { count: 0, date: getTodayDateString() };
    } catch (e) {
        console.error("Failed to parse usage data from localStorage:", e);
        return { count: 0, date: getTodayDateString() };
    }
}

/**
 * Saves usage data to localStorage.
 * @param {{count: number, date: string}} data The usage data object to save.
 */
function saveUsageData(data) {
    try {
        localStorage.setItem(MESSAGE_LIMIT_KEY, JSON.stringify(data));
    } catch (e) {
        console.error("Failed to save usage data to localStorage:", e);
    }
}

/**
 * Checks if the daily message limit has been reached for a free user.
 * @param {boolean} isPremium - Whether the current user is premium.
 * @returns {boolean} - True if the limit is reached, otherwise false.
 */
export function isMessageLimitReached(isPremium) {
    if (isPremium) {
        return false; // Premium users have no limit.
    }

    let usageData = getUsageData();
    const today = getTodayDateString();

    if (usageData.date !== today) {
        // It's a new day, reset the counter.
        usageData = { count: 0, date: today };
        saveUsageData(usageData);
    }

    return usageData.count >= DAILY_MESSAGE_LIMIT;
}

/**
 * Increments the message count for a free user for the current day.
 * @param {boolean} isPremium - Whether the current user is premium.
 */
export function incrementMessageCount(isPremium) {
    if (isPremium) {
        return; // Don't track for premium users.
    }

    let usageData = getUsageData();
    const today = getTodayDateString();

    if (usageData.date !== today) {
        // If the day changed between the check and the increment, reset first.
        usageData = { count: 1, date: today };
    } else {
        usageData.count += 1;
    }

    saveUsageData(usageData);
}
// *** END: ADDED FOR MESSAGE LIMIT ***


export function setActiveTool(toolName) {
    activeTool = toolName;
}

export function getActiveTool() {
    return activeTool;
}

export function setActiveToolPrefix(prefix) {
    activeToolPrefix = prefix;
}

export function getActiveToolPrefix() {
    return activeToolPrefix;
}

export function setChatSessions(newSessions) {
    chatSessions = newSessions;
}

export function setActiveChatId(id) {
    activeChatId = id;
}

export function setAttachedFile(file) {
    attachedFile = file;
}

export function setGenerating(status) {
    isGenerating = status;
}

export function setGlobalAbortController(controller) {
    globalAbortController = controller;
}

export function setCurrentUploadXHR(xhr) {
    currentUploadXHR = xhr;
}

export function getActiveChat() {
    return chatSessions.find(s => s.id === activeChatId);
}

export function saveSessions() {
    try {
        const sessionsToSave = JSON.parse(JSON.stringify(chatSessions));
        
        sessionsToSave.forEach(session => {
            session.messages.forEach(message => {
                if (message.parts) {
                    message.parts.forEach(part => {
                        if (part.base64Data) {
                            delete part.base64Data;
                        }
                        if (part.blobUrl) {
                            delete part.blobUrl;
                        }
                    });
                }
            });
        });

        localStorage.setItem('alphaChatSessions', JSON.stringify(sessionsToSave));
    } catch (e) {
        console.error("Failed to save sessions to localStorage:", e);
    }
}

export function loadSessions() {
    try {
        const saved = localStorage.getItem('alphaChatSessions');
        chatSessions = saved ? JSON.parse(saved) : [];
        chatSessions.forEach(session => {
            if (session.showThoughts === undefined) {
                session.showThoughts = false;
            }
            // *** START: MODIFIED - افزودن فیلد جدید به پیام‌های قدیمی برای سازگاری ***
            session.messages.forEach(message => {
                if (message.role === 'assistant' && message.wasGeneratedWithThoughts === undefined) {
                    message.wasGeneratedWithThoughts = false; 
                }
            });
            // *** END: MODIFIED ***
        });
    } catch (e) {
        console.error("Failed to load sessions from localStorage:", e);
        chatSessions = [];
    }
}

export function findLastIndex(array, predicate) {
    for (let i = array.length - 1; i >= 0; i--) {
        if (predicate(array[i])) { return i; }
    }
    return -1;
}

export function deleteMessage(chatId, messageIndex) {
    const chat = chatSessions.find(s => s.id === chatId);
    if (chat && chat.messages[messageIndex]) {
        chat.messages.splice(messageIndex, 1);
        saveSessions();
    }
}