// js/main.js

// --- IMPORTS ---
import { apiCall } from './api.js';
import { showMessage } from './utils.js';
import {
    renderAuthView,
    renderAdminDashboard,
    renderEmployeeDashboard,
    renderEditModal,
    renderChangePasswordModal,
    renderResetPasswordModal,
    renderRequestHistoryModal,
    handleViewNotesClick,
    renderArchiveView,
    renderTimeOffHistoryView,
    updatePendingRequestsList,
    renderEditTimeOffModal
} from './ui.js';

// --- STATE MANAGEMENT ---
let user = null;
let authToken = null;
let lastAdminTab = 'overview';
export { lastAdminTab };

// --- EVENT HANDLERS (The "Logic") ---
async function handleAuthSubmit(e) {
    e.preventDefault();
    const username = e.target.elements.username.value;
    const password = e.target.elements.password.value;
    const res = await apiCall('/login', 'POST', { username, password });

    if (res && res.success) {
        localStorage.setItem('authToken', res.data.token);
        localStorage.setItem('user', JSON.stringify(res.data.user));
        initializeApp();
    } else {
        showMessage(res?.data?.message || 'Login failed. Please check your credentials.', 'error');
    }
}

function handleSignOut(message) {
    localStorage.clear();
    authToken = null;
    user = null;
    if (message) {
        showMessage(message, 'success');
    }
    initializeApp();
}

const handlePunch = () => {
    apiCall('/punch', 'POST').then(res => res.success && renderEmployeeDashboard());
};

async function handleChangePassword(e) {
    e.preventDefault();
    const currentPassword = e.target.elements['modal-current-pw'].value;
    const newPassword = e.target.elements['modal-new-pw'].value;
    const res = await apiCall('/user/change-password', 'POST', { currentPassword, newPassword });
    if (res.success) {
        showMessage(res.data.message, 'success');
        document.getElementById('modal-container').innerHTML = '';
    }
}

async function handleTimeOffRequest(e) {
    e.preventDefault();
    const startDate = e.target.elements['start-date'].value;
    const endDate = e.target.elements['end-date'].value;
    const reason = e.target.elements['reason'].value;
    if (new Date(endDate) < new Date(startDate)) {
        return showMessage('End date cannot be before start date.', 'error');
    }
    const res = await apiCall('/user/request-time-off', 'POST', { startDate, endDate, reason });
    if (res.success) {
        showMessage(res.data.message, 'success');
        e.target.reset();
        renderEmployeeDashboard();
    }
}

async function handleViewRequestHistoryClick() {
    const res = await apiCall('/user/time-off-requests/history');
    if (res.success) {
        renderRequestHistoryModal(res.data);
    }
}

async function handleEditSubmit(e) {
    e.preventDefault();
    const id = e.target.elements['edit-id'].value;
    const punch_in_time = new Date(e.target.elements['edit-in'].value).toISOString();
    const punch_out_value = e.target.elements['edit-out'].value;
    const punch_out_time = punch_out_value ? new Date(punch_out_value).toISOString() : null;
    const res = await apiCall(`/admin/logs/${id}`, 'PUT', { punch_in_time, punch_out_time });
    if (res.success) {
        document.getElementById('modal-container').innerHTML = '';
        renderAdminDashboard();
        showMessage('Entry updated successfully.', 'success');
    }
}

const handleArchive = () => {
    if (confirm('Are you sure you want to archive all completed time entries? This action cannot be undone.')) {
        apiCall('/admin/archive', 'POST').then(res => {
            if(res.success) {
                showMessage('Records archived successfully.', 'success');
                renderAdminDashboard();
            }
        });
    }
};

async function handleCreateUser(e) {
    e.preventDefault();
    const username = e.target.elements['new-username'].value;
    const password = e.target.elements['new-password'].value;
    const role = e.target.elements['new-user-role'].value;
    const res = await apiCall('/admin/create-user', 'POST', { username, password, role });
    if (res.success) {
        showMessage(res.data.message, 'success');
        e.target.reset();
        renderAdminDashboard();
    }
}

async function handleAddPunch(e) {
    e.preventDefault();
    const selected = e.target.elements['add-punch-user'];
    const userId = selected.value;
    const username = selected.options[selected.selectedIndex].dataset.username;
    const punchInTime = new Date(e.target.elements['add-punch-in'].value).toISOString();
    const punchOutValue = e.target.elements['add-punch-out'].value;
    const punchOutTime = punchOutValue ? new Date(punchOutValue).toISOString() : null;
    const res = await apiCall('/admin/add-punch', 'POST', { userId, username, punchInTime, punchOutTime });
    if (res.success) {
        showMessage(res.data.message, 'success');
        e.target.reset();
        renderAdminDashboard();
    }
}

async function handleAddNote(e) {
    e.preventDefault();
    const userId = e.target.elements['note-user-select'].value;
    const noteText = e.target.elements['note-text'].value;
    if (!userId) {
        return showMessage('Please select an employee.', 'error');
    }
    const res = await apiCall('/admin/notes', 'POST', { userId, noteText });
    if (res.success) {
        showMessage(res.data.message, 'success');
        e.target.reset();
    }
}

async function handleResetPassword(e) {
    e.preventDefault();
    const username = e.target.elements['reset-username'].value;
    const newPassword = e.target.elements['reset-new-pw'].value;
    const res = await apiCall('/admin/reset-password', 'POST', { username, newPassword });
    if (res.success) {
        showMessage(res.data.message, 'success');
        document.getElementById('modal-container').innerHTML = '';
    }
}

function handleAdminDashboardClick(e) {
    const target = e.target.closest('button');
    if (!target) return;

    const { id, userid, username, role, noteId } = target.dataset;
    
    switch (target.id) {
        case 'view-archives-btn':
            renderArchiveView();
            return;
        case 'archive-btn':
            handleArchive();
            return;
        case 'view-time-off-history-btn':
            renderTimeOffHistoryView();
            return;
        case 'view-notes-btn':
            handleViewNotesClick();
            return;
    }

    if (target.classList.contains('approve-request-btn') || target.classList.contains('deny-request-btn')) {
        const status = target.classList.contains('approve-request-btn') ? 'approved' : 'denied';
        if (confirm(`Set this request to "${status}"?`)) {
            apiCall('/admin/update-time-off-status', 'POST', { requestId: id, status: status })
                .then(res => {
                    if (res.success) {
                        showMessage(`Request ${status}.`, 'success');
                        apiCall('/admin/time-off-requests/pending').then(requestsRes => {
                            if (requestsRes.success) {
                                updatePendingRequestsList(requestsRes.data);
                            }
                        });
                    }
                });
        }
        return;
    }

    if (target.classList.contains('set-pending-btn')) {
        if (confirm('Are you sure you want to move this request back to pending?')) {
            apiCall('/admin/update-time-off-status', 'POST', { requestId: id, status: 'pending' })
                .then(res => {
                    if (res.success) {
                        showMessage('Request status set to pending.', 'success');
                        renderTimeOffHistoryView();
                    }
                });
        }
        return;
    }

    if (target.classList.contains('admin-delete-request-btn')) {
        if (confirm('Are you sure you want to permanently delete this request? This cannot be undone.')) {
            apiCall(`/admin/time-off-requests/${id}`, 'DELETE')
                .then(res => {
                    if (res.success) {
                        showMessage('Request deleted.', 'success');
                        if (document.getElementById('tab-content-overview')) {
                            apiCall('/admin/time-off-requests/pending').then(requestsRes => {
                                if (requestsRes.success) {
                                    updatePendingRequestsList(requestsRes.data);
                                }
                            });
                        } else {
                            renderTimeOffHistoryView();
                        }
                    }
                });
        }
        return;
    }

    if (target.classList.contains('edit-btn')) renderEditModal(id, handleEditSubmit);
    if (target.classList.contains('delete-btn') && confirm('Delete this time entry?')) apiCall(`/admin/logs/${id}`, 'DELETE').then(res => res.success && renderAdminDashboard());
    if (target.classList.contains('force-clock-out-btn') && confirm(`Force clock out ${username}?`)) apiCall('/admin/force-clock-out', 'POST', { userId: userid }).then(res => res.success && renderAdminDashboard());
    if (target.classList.contains('reset-pw-btn')) renderResetPasswordModal(username, handleResetPassword);
    if (target.classList.contains('change-role-btn')) { const newRole = role === 'admin' ? 'employee' : 'admin'; if(confirm(`Change ${username} to ${newRole}?`)) apiCall('/admin/update-role', 'POST', { username, newRole }).then(res => res.success && renderAdminDashboard()); }
    if (target.classList.contains('delete-user-btn') && confirm(`PERMANENTLY DELETE user '${username}'?`)) apiCall(`/admin/delete-user/${username}`, 'DELETE').then(res => res.success && renderAdminDashboard());
    if (target.classList.contains('delete-note-btn')) { if (confirm('Delete this note?')) { apiCall(`/admin/notes/${noteId}`, 'DELETE').then(res => { if (res.success) { showMessage('Note deleted.', 'success'); handleViewNotesClick(); }});}}
}

async function handleEditTimeOffSubmit(e) {
    e.preventDefault();
    const id = e.target.elements['edit-request-id'].value;
    const startDate = e.target.elements['edit-start-date'].value;
    const endDate = e.target.elements['edit-end-date'].value;
    const reason = e.target.elements['edit-reason'].value;

    if (new Date(endDate) < new Date(startDate)) {
        return showMessage('End date cannot be before start date.', 'error');
    }

    const res = await apiCall(`/user/time-off-requests/${id}`, 'PUT', { startDate, endDate, reason });
    if (res.success) {
        showMessage(res.data.message, 'success');
        document.getElementById('modal-container').innerHTML = '';
        renderEmployeeDashboard();
    }
}

// --- LISTENER ATTACHMENT FUNCTIONS ---
export function attachAuthFormListener() {
    const form = document.getElementById('auth-form');
    if (form) form.addEventListener('submit', handleAuthSubmit);
}

export function attachEmployeeDashboardListeners() {
    const dashboard = document.getElementById('employee-dashboard');
    if (!dashboard) return;

    dashboard.addEventListener('click', async (e) => {
        const target = e.target;

        if (target.id === 'punch-btn') {
            handlePunch();
        }
        if (target.id === 'change-password-btn') {
            renderChangePasswordModal(handleChangePassword);
        }
        if (target.id === 'view-request-history-btn') {
            handleViewRequestHistoryClick();
        }
        if (target.classList.contains('delete-request-btn')) {
            const id = target.dataset.id;
            if (confirm('Are you sure you want to delete this time off request?')) {
                const res = await apiCall(`/user/time-off-requests/${id}`, 'DELETE');
                if (res.success) {
                    showMessage(res.data.message, 'success');
                    renderEmployeeDashboard();
                }
            }
        }
        if (target.classList.contains('edit-request-btn')) {
            const id = target.dataset.id;
            const res = await apiCall('/user/time-off-requests/history');
            if (res.success) {
                const requestToEdit = res.data.find(r => r.id == id);
                if (requestToEdit) {
                    renderEditTimeOffModal(requestToEdit, handleEditTimeOffSubmit);
                }
            }
        }
    });

    const timeOffForm = document.getElementById('time-off-form');
    if (timeOffForm) {
        timeOffForm.addEventListener('submit', handleTimeOffRequest);
    }
}

export function attachAdminDashboardListeners() {
    document.getElementById('admin-dashboard')?.addEventListener('click', handleAdminDashboardClick);
    document.getElementById('create-user-form')?.addEventListener('submit', handleCreateUser);
    document.getElementById('add-punch-form')?.addEventListener('submit', handleAddPunch);
    document.getElementById('add-note-form')?.addEventListener('submit', handleAddNote);
    setupTabbedInterface(); 
}

// --- APP INITIALIZER ---
function initializeApp() {
    authToken = localStorage.getItem('authToken');
    const userString = localStorage.getItem('user');
    user = userString ? JSON.parse(userString) : null;
    
    if (authToken && user) {
        const userControls = document.getElementById('nav-user-controls');
        userControls.classList.remove('hidden');
        userControls.querySelector('#welcome-message').textContent = `Welcome, ${user.username}`;
        if (user.role === 'admin') {
            renderAdminDashboard();
        } else {
            renderEmployeeDashboard();
        }
    } else {
        document.getElementById('nav-user-controls').classList.add('hidden');
        renderAuthView();
    }
}

// --- HELPERS ---
function setupTabbedInterface() {
    const tabsContainer = document.getElementById('admin-tabs-nav');
    const contentContainer = document.getElementById('admin-tabs-content');

    if (!tabsContainer || !contentContainer) return;

    tabsContainer.addEventListener('click', (e) => {
        const clickedTab = e.target.closest('.tab-btn');
        if (!clickedTab) return;

        const tabTarget = clickedTab.dataset.tab;
        lastAdminTab = tabTarget;

        tabsContainer.querySelectorAll('.tab-btn').forEach(btn => {
            btn.classList.remove('active-tab');
        });
        clickedTab.classList.add('active-tab');

        contentContainer.querySelectorAll('[id^="tab-content-"]').forEach(panel => {
            panel.classList.add('hidden');
        });
        document.getElementById(`tab-content-${tabTarget}`).classList.remove('hidden');
    });
}

// --- START THE APP ---
if ('serviceWorker' in navigator) {
  window.addEventListener('load', () => {
    navigator.serviceWorker.register('/sw.js')
      .then(registration => console.log('Service Worker registered! Scope:', registration.scope))
      .catch(err => console.error('Service Worker registration failed:', err));
  });
}

document.getElementById('sign-out-btn').addEventListener('click', () => handleSignOut('You have been signed out.'));
document.addEventListener('visibilitychange', () => {
    if (document.visibilityState === 'visible' && localStorage.getItem('user')) {
        initializeApp();
    }
});

initializeApp();