/**
 * Team Calendar Page
 * Shows presence and parking for all team members
 * Filtered by manager (manager-centric model)
 */

let currentUser = null;
let currentStartDate = null;
let viewMode = 'week'; // 'week' or 'month'
let managers = [];
let teamData = [];
let parkingDataLookup = {};
let parkingAssignmentLookup = {};
let selectedUserId = null;
let selectedDate = null;
let currentAssignmentId = null;

document.addEventListener('DOMContentLoaded', async () => {
    currentUser = await api.requireAuth();
    if (!currentUser) return;

    // Initialize start date based on week start preference
    const weekStartDay = currentUser.week_start_day || 0;
    currentStartDate = utils.getWeekStart(new Date(), weekStartDay);

    await loadManagers();
    await loadTeamData();
    renderCalendar();
    setupEventListeners();
});

async function loadManagers() {
    const response = await api.get('/api/managers');
    if (response && response.ok) {
        managers = await response.json();
        const select = document.getElementById('managerFilter');

        // Filter managers based on user role
        let filteredManagers = managers;
        if (currentUser.role === 'manager') {
            // Manager only sees themselves
            filteredManagers = managers.filter(m => m.id === currentUser.id);
        } else if (currentUser.role === 'employee') {
            // Employee only sees their own manager
            if (currentUser.manager_id) {
                filteredManagers = managers.filter(m => m.id === currentUser.manager_id);
            } else {
                filteredManagers = [];
            }
        }

        filteredManagers.forEach(manager => {
            const option = document.createElement('option');
            option.value = manager.id;
            const userCount = manager.managed_user_count || 0;
            option.textContent = `${manager.name} (${userCount} users)`;
            select.appendChild(option);
        });

        // Auto-select for managers and employees (they only see their team)
        if (filteredManagers.length === 1) {
            select.value = filteredManagers[0].id;
        }

        // Hide manager filter for employees (they can only see their team)
        if (currentUser.role === 'employee') {
            select.style.display = 'none';
        }
    }
}

function getDateRange() {
    let startDate = new Date(currentStartDate);
    let endDate = new Date(currentStartDate);

    if (viewMode === 'week') {
        endDate.setDate(endDate.getDate() + 6);
    } else {
        // Month view - start from first day of month
        startDate = new Date(currentStartDate.getFullYear(), currentStartDate.getMonth(), 1);
        endDate = new Date(currentStartDate.getFullYear(), currentStartDate.getMonth() + 1, 0);
    }

    return { startDate, endDate };
}

async function loadTeamData() {
    const { startDate, endDate } = getDateRange();
    const startStr = utils.formatDate(startDate);
    const endStr = utils.formatDate(endDate);

    let url = `/api/presence/team?start_date=${startStr}&end_date=${endStr}`;

    const managerFilter = document.getElementById('managerFilter').value;
    if (managerFilter) {
        url += `&manager_id=${managerFilter}`;
    }

    const response = await api.get(url);
    if (response && response.ok) {
        teamData = await response.json();
        // Build parking lookup with spot names and assignment IDs
        parkingDataLookup = {};
        parkingAssignmentLookup = {};
        teamData.forEach(member => {
            if (member.parking_info) {
                member.parking_info.forEach(p => {
                    const key = `${member.id}_${p.date}`;
                    parkingDataLookup[key] = p.spot_display_name || p.spot_id;
                    parkingAssignmentLookup[key] = p.id;
                });
            }
        });
    }
}

function renderCalendar() {
    const header = document.getElementById('calendarHeader');
    const body = document.getElementById('calendarBody');
    const { startDate, endDate } = getDateRange();

    // Update header text
    if (viewMode === 'week') {
        document.getElementById('currentWeek').textContent =
            `${utils.formatDateShort(startDate)} - ${utils.formatDateShort(endDate)}`;
    } else {
        document.getElementById('currentWeek').textContent =
            `${utils.getMonthName(startDate.getMonth())} ${startDate.getFullYear()}`;
    }

    // Calculate number of days
    const dayCount = Math.round((endDate - startDate) / (1000 * 60 * 60 * 24)) + 1;

    // Build header row
    const dayNames = ['Sun', 'Mon', 'Tue', 'Wed', 'Thu', 'Fri', 'Sat'];
    let headerHtml = '<th>Name</th><th>Manager</th>';

    for (let i = 0; i < dayCount; i++) {
        const date = new Date(startDate);
        date.setDate(date.getDate() + i);
        const dayOfWeek = date.getDay();
        const isWeekend = dayOfWeek === 0 || dayOfWeek === 6;
        const isHoliday = utils.isItalianHoliday(date);
        const isToday = date.toDateString() === new Date().toDateString();

        let classes = [];
        if (isWeekend) classes.push('weekend');
        if (isHoliday) classes.push('holiday');
        if (isToday) classes.push('today');

        headerHtml += `<th class="${classes.join(' ')}">
            <div>${dayNames[dayOfWeek].charAt(0)}</div>
            <div class="day-number">${date.getDate()}</div>
        </th>`;
    }
    header.innerHTML = headerHtml;

    // Build body rows
    if (teamData.length === 0) {
        body.innerHTML = `<tr><td colspan="${dayCount + 2}" class="text-center">No team members found</td></tr>`;
        return;
    }

    let bodyHtml = '';
    teamData.forEach(member => {
        bodyHtml += `<tr>
            <td class="member-name">${member.name || 'Unknown'}</td>
            <td class="member-manager">${member.manager_name || '-'}</td>`;

        for (let i = 0; i < dayCount; i++) {
            const date = new Date(startDate);
            date.setDate(date.getDate() + i);
            const dateStr = utils.formatDate(date);
            const dayOfWeek = date.getDay();
            const isWeekend = dayOfWeek === 0 || dayOfWeek === 6;
            const isHoliday = utils.isItalianHoliday(date);

            const presence = member.presences.find(p => p.date === dateStr);
            const parkingKey = `${member.id}_${dateStr}`;
            const parkingSpot = parkingDataLookup[parkingKey];
            const hasParking = member.parking_dates && member.parking_dates.includes(dateStr);
            const isToday = date.toDateString() === new Date().toDateString();

            let cellClasses = ['calendar-cell'];
            if (isWeekend) cellClasses.push('weekend');
            if (isHoliday) cellClasses.push('holiday');
            if (isToday) cellClasses.push('today');
            if (presence) cellClasses.push(`status-${presence.status}`);

            // Show parking badge instead of just 'P'
            let parkingBadge = '';
            if (hasParking) {
                const spotName = parkingSpot || 'P';
                parkingBadge = `<span class="parking-badge-sm">${spotName}</span>`;
            }

            bodyHtml += `<td class="${cellClasses.join(' ')}" data-user-id="${member.id}" data-date="${dateStr}" data-user-name="${member.name || ''}">${parkingBadge}</td>`;
        }

        bodyHtml += '</tr>';
    });
    body.innerHTML = bodyHtml;

    // Add click handlers to cells (only for admins and managers)
    if (currentUser.role === 'admin' || currentUser.role === 'manager') {
        body.querySelectorAll('.calendar-cell').forEach(cell => {
            cell.style.cursor = 'pointer';
            cell.addEventListener('click', () => {
                const userId = cell.dataset.userId;
                const date = cell.dataset.date;
                const userName = cell.dataset.userName;
                openDayModal(userId, date, userName);
            });
        });
    }
}

function openDayModal(userId, dateStr, userName) {
    selectedUserId = userId;
    selectedDate = dateStr;

    const modal = document.getElementById('dayModal');
    document.getElementById('dayModalTitle').textContent = utils.formatDateDisplay(dateStr);
    document.getElementById('dayModalUser').textContent = userName;

    // Find current status and parking
    const member = teamData.find(m => m.id === userId);
    const presence = member?.presences.find(p => p.date === dateStr);
    const parkingKey = `${userId}_${dateStr}`;
    const parkingSpot = parkingDataLookup[parkingKey];
    const assignmentId = parkingAssignmentLookup[parkingKey];

    // Highlight current status
    document.querySelectorAll('#dayModal .status-btn').forEach(btn => {
        const status = btn.dataset.status;
        if (presence && presence.status === status) {
            btn.classList.add('active');
        } else {
            btn.classList.remove('active');
        }
    });

    // Update parking section
    const parkingSection = document.getElementById('parkingSection');
    const parkingInfo = document.getElementById('parkingInfo');

    if (parkingSpot) {
        parkingSection.style.display = 'block';
        parkingInfo.innerHTML = `<strong>Parking:</strong> Spot ${parkingSpot}`;
        currentAssignmentId = assignmentId;
    } else {
        parkingSection.style.display = 'none';
        currentAssignmentId = null;
    }

    modal.style.display = 'flex';
}

async function markPresence(status) {
    if (!selectedUserId || !selectedDate) return;

    const response = await api.post('/api/presence/admin/mark', {
        user_id: selectedUserId,
        date: selectedDate,
        status: status
    });

    if (response && response.ok) {
        document.getElementById('dayModal').style.display = 'none';
        await loadTeamData();
        renderCalendar();
    } else {
        const error = await response.json();
        alert(error.detail || 'Failed to mark presence');
    }
}

async function clearPresence() {
    if (!selectedUserId || !selectedDate) return;
    if (!confirm('Clear presence for this date?')) return;

    const response = await api.delete(`/api/presence/admin/${selectedUserId}/${selectedDate}`);
    if (response && response.ok) {
        document.getElementById('dayModal').style.display = 'none';
        await loadTeamData();
        renderCalendar();
    }
}

async function openReassignModal() {
    if (!currentAssignmentId) return;

    // Load eligible users
    const response = await api.get(`/api/parking/eligible-users/${currentAssignmentId}`);
    if (!response || !response.ok) {
        const error = await response.json();
        alert(error.detail || 'Failed to load eligible users');
        return;
    }

    const users = await response.json();
    const select = document.getElementById('reassignUser');
    select.innerHTML = '<option value="">Select user...</option>';

    if (users.length === 0) {
        select.innerHTML = '<option value="">No eligible users available</option>';
    } else {
        users.forEach(user => {
            const option = document.createElement('option');
            option.value = user.id;
            option.textContent = user.name;
            select.appendChild(option);
        });
    }

    // Get spot info
    const parkingKey = `${selectedUserId}_${selectedDate}`;
    const spotName = parkingDataLookup[parkingKey] || 'Unknown';
    document.getElementById('reassignSpotInfo').textContent = `Spot ${spotName}`;

    document.getElementById('dayModal').style.display = 'none';
    document.getElementById('reassignModal').style.display = 'flex';
}

async function confirmReassign() {
    const newUserId = document.getElementById('reassignUser').value;

    if (!currentAssignmentId || !newUserId) {
        alert('Please select a user');
        return;
    }

    const response = await api.post('/api/parking/reassign-spot', {
        assignment_id: currentAssignmentId,
        new_user_id: newUserId
    });

    if (response && response.ok) {
        await loadTeamData();
        renderCalendar();
        document.getElementById('reassignModal').style.display = 'none';
    } else {
        const error = await response.json();
        alert(error.detail || 'Failed to reassign parking spot');
    }
}

function setupEventListeners() {
    // Navigation (prev/next)
    document.getElementById('prevWeek').addEventListener('click', async () => {
        if (viewMode === 'week') {
            currentStartDate.setDate(currentStartDate.getDate() - 7);
        } else {
            currentStartDate.setMonth(currentStartDate.getMonth() - 1);
        }
        await loadTeamData();
        renderCalendar();
    });

    document.getElementById('nextWeek').addEventListener('click', async () => {
        if (viewMode === 'week') {
            currentStartDate.setDate(currentStartDate.getDate() + 7);
        } else {
            currentStartDate.setMonth(currentStartDate.getMonth() + 1);
        }
        await loadTeamData();
        renderCalendar();
    });

    // View toggle (week/month)
    document.getElementById('viewToggle').addEventListener('change', async (e) => {
        viewMode = e.target.value;
        if (viewMode === 'month') {
            // Set to first day of current month
            currentStartDate = new Date(currentStartDate.getFullYear(), currentStartDate.getMonth(), 1);
        } else {
            // Set to current week start
            const weekStartDay = currentUser.week_start_day || 0;
            currentStartDate = utils.getWeekStart(new Date(), weekStartDay);
        }
        await loadTeamData();
        renderCalendar();
    });

    // Manager filter
    document.getElementById('managerFilter').addEventListener('change', async () => {
        await loadTeamData();
        renderCalendar();
    });

    // Day modal
    document.getElementById('closeDayModal').addEventListener('click', () => {
        document.getElementById('dayModal').style.display = 'none';
    });

    document.querySelectorAll('#dayModal .status-btn').forEach(btn => {
        btn.addEventListener('click', () => markPresence(btn.dataset.status));
    });

    document.getElementById('clearDayBtn').addEventListener('click', clearPresence);
    document.getElementById('reassignParkingBtn').addEventListener('click', openReassignModal);

    utils.setupModalClose('dayModal');

    // Reassign modal
    document.getElementById('closeReassignModal').addEventListener('click', () => {
        document.getElementById('reassignModal').style.display = 'none';
    });
    document.getElementById('cancelReassign').addEventListener('click', () => {
        document.getElementById('reassignModal').style.display = 'none';
    });
    document.getElementById('confirmReassign').addEventListener('click', confirmReassign);
    utils.setupModalClose('reassignModal');
}