/**
 * tableManager.js - Table management functionality
 * 
 * This module handles all table-related operations including populating,
 * updating, and managing the data display in tables.
 */

import AppState from './state.js';
// import { formatTimeToGMT4, formatDurationHours } from './formatters.js'; // formatTimeToGMT4 likely not needed
import { formatDurationHours } from './formatters.js'; // Keep for consistency if displaying hours
import { formatDateForDisplay } from './dateUtils.js';
import { getUserStateDisplay } from './userStates.js';
// The userActivityModal is invoked via a custom event 'user-activity-requested'.
// Direct import of userActivity.js is not needed here as userActivity.js listens for the event.
// // Import will be added when userActivity module is created 
// // import { showUserActivityModal } from './userActivity.js';

/**
 * Helper function to determine if the "First Login Time" column should be hidden.
 * This column is being removed for the new real_work_hours display.
 * @returns {boolean} - True, as it's always hidden now.
 */
function _alwaysHideLoginTime() {
    return true; 
}

/**
 * Helper function to show a message in the table body with correct colspan.
 * @param {string} message - The message to display.
 * @param {string} cssClass - CSS class for the message (e.g., 'text-danger', 'text-muted').
 */
function _showTableMessage(message, cssClass = 'text-muted') {
    const reportBody = document.getElementById('reportBody');
    if (!reportBody) {
        console.error("Table reportBody not found in _showTableMessage.");
        return;
    }
    // Try to determine current period and day for colspan, even if AppState is partially available
    let currentPeriodForColspan = 'daily'; // Default if AppState not fully usable
    let selectedWeekDayForColspan = null;
    if (AppState && typeof AppState.getCurrentPeriod === 'function') {
        currentPeriodForColspan = AppState.getCurrentPeriod();
    }
    if (AppState && typeof AppState.getSelectedWeekDay === 'function') {
        selectedWeekDayForColspan = AppState.getSelectedWeekDay();
    }
    
    const hideLogin = _alwaysHideLoginTime();
    const colspan = hideLogin ? 3 : 4;
    reportBody.innerHTML = `<tr><td colspan="${colspan}" class="text-center ${cssClass}">${message}</td></tr>`;
}

/**
 * Public function to show a message (e.g., error or custom status) in the main report table.
 * @param {string} message - The message to display.
 * @param {boolean} isError - If true, cssClass will be 'text-danger', otherwise 'text-muted'.
 */
export function showReportTableMessage(message, isError = false) {
    _showTableMessage(message, isError ? 'text-danger' : 'text-muted');
}

/**
 * Populate the main report table with data
 * @param {Array} data - Report data to display
 * @param {boolean} isAutoRefresh - Whether this is an auto-refresh operation
 */
export function populateTable(data, isAutoRefresh = false) {
    const reportBody = document.getElementById('reportBody');
    const periodHeader = document.getElementById('periodHeader');
    
    if (!AppState || typeof AppState.setReportData !== 'function' || typeof AppState.getCurrentPeriod !== 'function' || typeof AppState.getSelectedWeekDay !== 'function') {
        console.error("AppState or its methods not available in populateTable");
        _showTableMessage("Error loading table: AppState not ready.", "text-danger");
        return;
    }
    if (!reportBody || !periodHeader) {
        console.error("Table reportBody or periodHeader not found in populateTable.");
        // If reportBody is missing, _showTableMessage won't work either.
        return;
    }

    AppState.setReportData([...data]);
    
    if (!isAutoRefresh) {
        const currentPeriod = AppState.getCurrentPeriod();
        switch (currentPeriod) {
            case 'daily': periodHeader.textContent = 'Day'; break;
            case 'weekly': periodHeader.textContent = 'Date'; break;
            case 'monthly': periodHeader.textContent = 'Date'; break;
            default: periodHeader.textContent = 'Date';
        }

        // Remove this block as it's hiding the State column header
        // const firstLoginHeader = document.querySelector('#reportTable th:nth-child(4)');
        // const hideLoginTime = _alwaysHideLoginTime();
        
        // if (firstLoginHeader) {
        //     firstLoginHeader.style.display = hideLoginTime ? 'none' : '';
        // } else {
        //     console.warn("First login time header cell not found for show/hide logic.");
        // }

        // Removed the data.length === 0 check here, populateTableRows will handle it.
    }

    if (isAutoRefresh && reportBody.children.length > 0 && data.length > 0) { // Only update if there's data
        updateTableData(data);
    } else {
        populateTableRows(data); // Let populateTableRows handle empty data message too
    }
}

/**
 * Populate table rows with data
 * @param {Array} data - Data to display in the table
 */
export function populateTableRows(data) {
    const reportBody = document.getElementById('reportBody');
    if (!AppState || typeof AppState.getCurrentPeriod !== 'function' || typeof AppState.getSelectedWeekDay !== 'function') {
        console.error("AppState or its methods not available in populateTableRows");
        _showTableMessage("Error populating rows: AppState not ready.", "text-danger");
        return;
    }
    // reportBody check is now implicitly handled by _showTableMessage if we reach here
    // but _showTableMessage has its own check.

    const currentPeriod = AppState.getCurrentPeriod();
    const selectedWeekDay = AppState.getSelectedWeekDay();
    const hideLogin = _alwaysHideLoginTime();
    
    reportBody.innerHTML = ''; 

    if (!data || data.length === 0) {
        // Use the helper for "no data" message as well
        _showTableMessage("No data available.", "text-muted");
        return;
    }
    
    data.forEach(entry => {
        const row = document.createElement('tr');
        let periodValue = '';
        // Determine which period key to use based on currentPeriod
        switch (currentPeriod) {
            case 'daily': periodValue = entry.day; break;
            case 'weekly': periodValue = entry.week_start; break;
            case 'monthly': periodValue = entry.month_start; break;
        }
        
        // Format date string from ISO (YYYY-MM-DD) to DD/MM/YYYY
        let formattedPeriod = formatDateForDisplay(entry.work_date);
        
        // Get user state
        const userStateDisplay = getUserStateDisplay(entry.username);

        // Show/hide First Login Time column based on period and day selection
        // const hideLogin = _alwaysHideLoginTime(); 
        // Already defined above
        
        if (hideLogin) {
            // Don't include First Login Time cell
            row.innerHTML = `
                <td><a class="user-link" data-user="${entry.username}">${entry.username}</a></td>
                <td>${formattedPeriod || 'N/A'}</td>
                <td>${formatDurationHours(entry.real_hours_counted)}</td>
                <td class="user-state-cell">${userStateDisplay}</td>
            `;
        }
        reportBody.appendChild(row);
    });
    
    // Remove old event listeners if any were attached directly, though innerHTML='' should handle it.
    // Add a single event listener to reportBody for user links (event delegation)
    // This replaces: document.querySelectorAll('.user-link').forEach(link => { ... });

    // Ensure only one listener is attached, remove if already present
    if (reportBody._userLinkClickListener) {
        reportBody.removeEventListener('click', reportBody._userLinkClickListener);
    }

    reportBody._userLinkClickListener = function(event) {
        const targetLink = event.target.closest('.user-link');
        if (targetLink) {
            event.preventDefault(); // Prevent default anchor action if any
            const username = targetLink.getAttribute('data-user');
            if (username) {
                // Dispatch a custom event. userActivity.js listens for this event
                // to show the modal, as initialized in dashboard.js.
                const customEvent = new CustomEvent('user-activity-requested', { 
                    detail: { username: username }
                });
                document.dispatchEvent(customEvent);
            }
        }
    };
    reportBody.addEventListener('click', reportBody._userLinkClickListener);
}

/**
 * Update existing table data without full redraw (for smoother auto-refresh)
 * @param {Array} data - Updated data to display
 */
export function updateTableData(data) {
    const reportBody = document.getElementById('reportBody');

    if (!AppState || typeof AppState.getCurrentPeriod !== 'function' || typeof AppState.getSelectedWeekDay !== 'function') {
        console.error("AppState or its methods not available in updateTableData");
        return;
    }
    if (!reportBody) {
        console.error("Table reportBody not found in updateTableData.");
        return;
    }

    // Log update for debugging
    console.log('Updating table data during auto-refresh:', data);

    // Create a map of username + work_date to data for quick lookup
    const dataMap = {};
    data.forEach(entry => {
        // Use a composite key of username and work_date to uniquely identify each row
        const key = `${entry.username}_${entry.work_date}`;
        dataMap[key] = entry;
    });
    
    // For each row in the table, update the data
    const rows = reportBody.querySelectorAll('tr');
    
    rows.forEach(row => {
        const userLink = row.querySelector('.user-link');
        if (!userLink) return;
        
        const username = userLink.getAttribute('data-user');
        
        // Get the date from the second cell
        const dateCell = row.querySelector('td:nth-child(2)');
        if (!dateCell) return;
        
        // Try to find matching data for this row
        // We need to try different formats since the display format might differ from the API format
        const displayedDate = dateCell.textContent;
        
        // First try direct match with username only (if we don't have date in key)
        let userData = null;
        
        // Try to match by username and work_date from the data
        for (const entry of data) {
            if (entry.username === username) {
                // Format the date for display to compare with what's in the cell
                const formattedDate = formatDateForDisplay(entry.work_date);
                if (formattedDate === displayedDate || displayedDate === 'N/A') {
                    userData = entry;
                    break;
                }
            }
        }
        
        if (userData) {
            // Update duration - make sure to use real_hours_counted
            const durationCell = row.querySelector('td:nth-child(3)');
            if (durationCell) {
                durationCell.textContent = formatDurationHours(userData.real_hours_counted);
                // Log successful updates for debugging
                console.log(`Updated ${username} real_hours_counted to ${userData.real_hours_counted}`);
            }
            
            // Update state
            const stateCell = row.querySelector('td:last-child');
            if (stateCell) {
                stateCell.innerHTML = getUserStateDisplay(username);
            }
        } else {
            console.warn(`No matching data found for user ${username} with date ${displayedDate}`);
        }
    });
}