// TeeTracker - Main Application

// ============================================
// Data Storage & Management
// ============================================

const STORAGE_KEY_TEAS = 'teatracker_teas';
const STORAGE_KEY_ENTRIES = 'teatracker_entries';

class TeaTracker {
    constructor() {
        this.teas = this.loadTeas();
        this.entries = this.loadEntries();
        this.currentTeaId = null;
        this.charts = {};
        
        this.init();
    }
    
    // Load data from localStorage
    loadTeas() {
        const data = localStorage.getItem(STORAGE_KEY_TEAS);
        if (!data) return [];
        
        const teas = JSON.parse(data);
        // Migrate existing teas to add organic field if missing
        return teas.map(tea => ({
            ...tea,
            organic: tea.organic !== undefined ? tea.organic : false
        }));
    }
    
    loadEntries() {
        const data = localStorage.getItem(STORAGE_KEY_ENTRIES);
        return data ? JSON.parse(data) : [];
    }
    
    // Save data to localStorage
    saveTeas() {
        localStorage.setItem(STORAGE_KEY_TEAS, JSON.stringify(this.teas));
    }
    
    saveEntries() {
        localStorage.setItem(STORAGE_KEY_ENTRIES, JSON.stringify(this.entries));
    }
    
    // Generate unique ID
    generateId() {
        return Date.now().toString(36) + Math.random().toString(36).substr(2);
    }
    
    // Get tea by ID
    getTeaById(id) {
        return this.teas.find(tea => tea.id === id);
    }
    
    // Get tea index by ID
    getTeaIndexById(id) {
        return this.teas.findIndex(tea => tea.id === id);
    }
    
    // ============================================
    // Tea Management
    // ============================================
    
    addTea(tea) {
        const newTea = {
            id: this.generateId(),
            name: tea.name,
            type: tea.type,
            brand: tea.brand || '',
            description: tea.description || '',
            color: tea.color || '#8B4513',
            organic: tea.organic || false,
            createdAt: new Date().toISOString()
        };
        this.teas.push(newTea);
        this.saveTeas();
        return newTea;
    }
    
    updateTea(id, updates) {
        const index = this.getTeaIndexById(id);
        if (index !== -1) {
            this.teas[index] = { ...this.teas[index], ...updates };
            this.saveTeas();
            return this.teas[index];
        }
        return null;
    }
    
    deleteTea(id) {
        const index = this.getTeaIndexById(id);
        if (index !== -1) {
            // Remove entries that reference this tea
            this.entries = this.entries.filter(entry => entry.teaId !== id);
            this.saveEntries();
            
            this.teas.splice(index, 1);
            this.saveTeas();
            return true;
        }
        return false;
    }
    
    // ============================================
    // Entry Management
    // ============================================
    
    addEntry(entry) {
        const newEntry = {
            id: this.generateId(),
            teaId: entry.teaId,
            date: entry.date,
            time: entry.time || '',
            amount: parseInt(entry.amount) || 1,
            notes: entry.notes || '',
            createdAt: new Date().toISOString()
        };
        this.entries.push(newEntry);
        this.saveEntries();
        return newEntry;
    }
    
    deleteEntry(id) {
        const index = this.entries.findIndex(entry => entry.id === id);
        if (index !== -1) {
            this.entries.splice(index, 1);
            this.saveEntries();
            return true;
        }
        return false;
    }
    
    // ============================================
    // Statistics
    // ============================================
    
    getTotalCups() {
        return this.entries.reduce((sum, entry) => sum + entry.amount, 0);
    }
    
    getTodayCups() {
        const today = new Date().toISOString().split('T')[0];
        return this.entries
            .filter(entry => entry.date === today)
            .reduce((sum, entry) => sum + entry.amount, 0);
    }
    
    getCupsByPeriod(period) {
        const now = new Date();
        let startDate;
        
        switch (period) {
            case 'today':
                startDate = new Date(now.getFullYear(), now.getMonth(), now.getDate());
                break;
            case 'week':
                startDate = new Date(now.getTime() - 7 * 24 * 60 * 60 * 1000);
                break;
            case 'month':
                startDate = new Date(now.getFullYear(), now.getMonth() - 1, now.getDate());
                break;
            case 'year':
                startDate = new Date(now.getFullYear() - 1, now.getMonth(), now.getDate());
                break;
            case 'all':
                startDate = new Date(0);
                break;
            default:
                startDate = new Date(now.getTime() - 7 * 24 * 60 * 60 * 1000);
        }
        
        return this.entries
            .filter(entry => new Date(entry.date) >= startDate)
            .reduce((sum, entry) => sum + entry.amount, 0);
    }
    
    getWeekCups() {
        const now = new Date();
        const weekAgo = new Date(now.getTime() - 7 * 24 * 60 * 60 * 1000);
        
        return this.entries
            .filter(entry => new Date(entry.date) >= weekAgo)
            .reduce((sum, entry) => sum + entry.amount, 0);
    }
    
    getEntriesByPeriod(period) {
        const now = new Date();
        let startDate;
        
        switch (period) {
            case 'today':
                startDate = new Date(now.getFullYear(), now.getMonth(), now.getDate());
                break;
            case 'week':
                startDate = new Date(now.getTime() - 7 * 24 * 60 * 60 * 1000);
                break;
            case 'month':
                startDate = new Date(now.getFullYear(), now.getMonth() - 1, now.getDate());
                break;
            case 'year':
                startDate = new Date(now.getFullYear() - 1, now.getMonth(), now.getDate());
                break;
            case 'all':
                startDate = new Date(0);
                break;
            default:
                startDate = new Date(now.getTime() - 7 * 24 * 60 * 60 * 1000);
        }
        
        return this.entries.filter(entry => new Date(entry.date) >= startDate);
    }
    
    getCupsByPeriod(period) {
        const entries = this.getEntriesByPeriod(period);
        return entries.reduce((sum, entry) => sum + entry.amount, 0);
    }
    
    getCupsByTeaType(period = 'all') {
        const entries = this.getEntriesByPeriod(period);
        const typeCounts = {};
        
        entries.forEach(entry => {
            const tea = this.getTeaById(entry.teaId);
            if (tea) {
                typeCounts[tea.type] = (typeCounts[tea.type] || 0) + entry.amount;
            }
        });
        
        return typeCounts;
    }
    
    getCupsByTea(period = 'all') {
        const entries = this.getEntriesByPeriod(period);
        const teaCounts = {};
        
        entries.forEach(entry => {
            const tea = this.getTeaById(entry.teaId);
            if (tea) {
                teaCounts[tea.name] = (teaCounts[tea.name] || 0) + entry.amount;
            }
        });
        
        return teaCounts;
    }
    
    getDailyConsumption(period = 'week') {
        const entries = this.getEntriesByPeriod(period);
        const dailyCounts = {};
        
        entries.forEach(entry => {
            const date = entry.date;
            dailyCounts[date] = (dailyCounts[date] || 0) + entry.amount;
        });
        
        return dailyCounts;
    }
    
    getEntriesByPeriod(period) {
        const now = new Date();
        let startDate;
        
        switch (period) {
            case 'week':
                startDate = new Date(now.getTime() - 7 * 24 * 60 * 60 * 1000);
                break;
            case 'month':
                startDate = new Date(now.getFullYear(), now.getMonth() - 1, now.getDate());
                break;
            case 'year':
                startDate = new Date(now.getFullYear() - 1, now.getMonth(), now.getDate());
                break;
            case 'all':
                startDate = new Date(0);
                break;
            default:
                startDate = new Date(now.getTime() - 7 * 24 * 60 * 60 * 1000);
        }
        
        return this.entries.filter(entry => new Date(entry.date) >= startDate);
    }
    
    getMostConsumedTea(period = 'all') {
        const teaCounts = this.getCupsByTea(period);
        let maxCount = 0;
        let mostConsumed = null;
        
        for (const [teaName, count] of Object.entries(teaCounts)) {
            if (count > maxCount) {
                maxCount = count;
                mostConsumed = teaName;
            }
        }
        
        return { name: mostConsumed, count: maxCount };
    }
    
    getAverageDailyConsumption(period = 'month') {
        const entries = this.getEntriesByPeriod(period);
        if (entries.length === 0) return 0;
        
        const totalDays = this.countUniqueDays(entries);
        const totalCups = entries.reduce((sum, entry) => sum + entry.amount, 0);
        
        return Math.round(totalCups / totalDays);
    }
    
    countUniqueDays(entries) {
        const days = new Set();
        entries.forEach(entry => days.add(entry.date));
        return days.size;
    }
    
    // ============================================
    // UI Initialization
    // ============================================
    
    init() {
        this.setupEventListeners();
        this.renderAll();
        this.initCharts();
    }
    
    setupEventListeners() {
        // Tab navigation
        document.querySelectorAll('.tab-button').forEach(button => {
            button.addEventListener('click', (e) => this.switchTab(e.target.dataset.tab));
        });
        
        // Add tea button
        document.getElementById('add-tea-btn').addEventListener('click', () => this.openTeaModal());
        
        // Tea modal
        document.getElementById('close-modal').addEventListener('click', () => this.closeTeaModal());
        document.getElementById('tea-form').addEventListener('submit', (e) => this.handleTeaFormSubmit(e));
        document.getElementById('delete-tea-btn').addEventListener('click', () => this.handleDeleteTea());
        
        // Confirm modal
        document.getElementById('close-confirm').addEventListener('click', () => this.closeConfirmModal());
        document.getElementById('confirm-no').addEventListener('click', () => this.closeConfirmModal());
        document.getElementById('confirm-yes').addEventListener('click', () => this.confirmDelete());
        
        // Track form
        document.getElementById('track-form').addEventListener('submit', (e) => this.handleTrackFormSubmit(e));
        document.getElementById('cancel-track').addEventListener('click', () => this.resetTrackForm());
        
        // Tea search and filter
        document.getElementById('tea-search').addEventListener('input', (e) => this.filterTeas());
        document.getElementById('tea-type-filter').addEventListener('change', (e) => this.filterTeas());
        
        // Stats period filter
        document.getElementById('stats-period').addEventListener('change', (e) => this.updateStats());
        
        // Close modals on outside click
        document.getElementById('tea-modal').addEventListener('click', (e) => {
            if (e.target.id === 'tea-modal') this.closeTeaModal();
        });
        
        document.getElementById('confirm-modal').addEventListener('click', (e) => {
            if (e.target.id === 'confirm-modal') this.closeConfirmModal();
        });
    }
    
    switchTab(tabId) {
        // Save current form data if needed
        
        // Switch tabs
        document.querySelectorAll('.tab-button').forEach(button => {
            button.classList.toggle('active', button.dataset.tab === tabId);
        });
        
        document.querySelectorAll('.tab-pane').forEach(pane => {
            pane.classList.toggle('active', pane.id === tabId);
        });
        
        // Refresh content for specific tabs
        if (tabId === 'teas') {
            this.renderTeasList();
        } else if (tabId === 'track') {
            this.renderTrackForm();
        } else if (tabId === 'stats') {
            this.updateStats();
        } else if (tabId === 'dashboard') {
            this.updateDashboard();
        }
    }
    
    renderAll() {
        this.updateDashboard();
        this.renderTeasList();
        this.renderTrackForm();
        this.updateStats();
    }
    
    // ============================================
    // Dashboard
    // ============================================
    
    updateDashboard() {
        document.getElementById('total-cups').textContent = `${this.getTotalCups()} Tassen`;
        document.getElementById('today-cups').textContent = `${this.getTodayCups()} Tassen`;
        document.getElementById('week-cups').textContent = `${this.getWeekCups()} Tassen`;
        document.getElementById('total-teas').textContent = `${this.teas.length} Sorten`;
        
        this.renderRecentEntries();
    }
    
    renderRecentEntries() {
        const container = document.getElementById('recent-entries');
        const recentEntries = [...this.entries]
            .sort((a, b) => new Date(b.createdAt) - new Date(a.createdAt))
            .slice(0, 5);
        
        if (recentEntries.length === 0) {
            container.innerHTML = `
                <div class="empty-state">
                    <div class="empty-state-icon">📝</div>
                    <div class="empty-state-text">Keine Einträge vorhanden</div>
                    <div class="empty-state-subtext">Fange an, deinen Tee-Konsum zu tracken!</div>
                </div>
            `;
            return;
        }
        
        container.innerHTML = recentEntries.map(entry => {
            const tea = this.getTeaById(entry.teaId);
            const date = new Date(entry.date);
            const formattedDate = date.toLocaleDateString('de-DE');
            const formattedTime = entry.time ? entry.time.substring(0, 5) : '';
            
            return `
                <div class="activity-item">
                    <div class="activity-info">
                        <div class="activity-tea">${tea ? tea.name : 'Unbekannter Tee'} ${tea && tea.organic ? '<span class="organic-badge" title="Bio-Tee">🌱</span>' : ''}</div>
                        <div class="activity-details">${formattedDate} ${formattedTime ? `um ${formattedTime}` : ''}</div>
                    </div>
                    <div class="activity-amount">${entry.amount} Tasse${entry.amount > 1 ? 'n' : ''}</div>
                </div>
            `;
        }).join('');
    }
    
    // ============================================
    // Tea Management UI
    // ============================================
    
    renderTeasList() {
        const container = document.getElementById('teas-list');
        
        if (this.teas.length === 0) {
            container.innerHTML = `
                <div class="empty-state">
                    <div class="empty-state-icon">🍵</div>
                    <div class="empty-state-text">Keine Tee-Sorten vorhanden</div>
                    <div class="empty-state-subtext">Klicke auf "Tee hinzufügen", um deine erste Sorte anzulegen</div>
                </div>
            `;
            return;
        }
        
        container.innerHTML = this.teas.map(tea => `
            <div class="tea-card" data-id="${tea.id}">
                <div class="tea-card-header">
                    <div>
                        <h3 class="tea-name">${tea.name} ${tea.organic ? '<span class="organic-badge" title="Bio-Tee">🌱</span>' : ''}</h3>
                        <span class="tea-type">${tea.type}</span>
                    </div>
                </div>
                ${tea.brand ? `<div class="tea-brand">Marke: ${tea.brand}</div>` : ''}
                ${tea.description ? `<div class="tea-description">${tea.description}</div>` : ''}
                <div class="tea-actions">
                    <button class="tea-action-btn tea-edit-btn" onclick="app.editTea('${tea.id}')">Bearbeiten</button>
                    <button class="tea-action-btn tea-delete-btn" onclick="app.showDeleteTeaConfirm('${tea.id}')">Löschen</button>
                </div>
            </div>
        `).join('');
    }
    
    filterTeas() {
        const searchTerm = document.getElementById('tea-search').value.toLowerCase();
        const typeFilter = document.getElementById('tea-type-filter').value;
        
        const filteredTeas = this.teas.filter(tea => {
            const matchesSearch = tea.name.toLowerCase().includes(searchTerm) ||
                                 tea.brand.toLowerCase().includes(searchTerm) ||
                                 tea.description.toLowerCase().includes(searchTerm);
            const matchesType = typeFilter === 'all' || tea.type === typeFilter;
            return matchesSearch && matchesType;
        });
        
        const container = document.getElementById('teas-list');
        
        if (filteredTeas.length === 0) {
            container.innerHTML = `
                <div class="empty-state">
                    <div class="empty-state-icon">🔍</div>
                    <div class="empty-state-text">Keine Tee-Sorten gefunden</div>
                    <div class="empty-state-subtext">Versuche andere Suchbegriffe oder Filter</div>
                </div>
            `;
            return;
        }
        
        container.innerHTML = filteredTeas.map(tea => `
            <div class="tea-card" data-id="${tea.id}">
                <div class="tea-card-header">
                    <div>
                        <h3 class="tea-name">${tea.name} ${tea.organic ? '<span class="organic-badge" title="Bio-Tee">🌱</span>' : ''}</h3>
                        <span class="tea-type">${tea.type}</span>
                    </div>
                </div>
                ${tea.brand ? `<div class="tea-brand">Marke: ${tea.brand}</div>` : ''}
                ${tea.description ? `<div class="tea-description">${tea.description}</div>` : ''}
                <div class="tea-actions">
                    <button class="tea-action-btn tea-edit-btn" onclick="app.editTea('${tea.id}')">Bearbeiten</button>
                    <button class="tea-action-btn tea-delete-btn" onclick="app.showDeleteTeaConfirm('${tea.id}')">Löschen</button>
                </div>
            </div>
        `).join('');
    }
    
    // Render recent entries on track page
    renderTrackRecentEntries() {
        const container = document.getElementById('track-recent-entries');
        const recentEntries = [...this.entries]
            .sort((a, b) => new Date(b.createdAt) - new Date(a.createdAt))
            .slice(0, 10);
        
        if (recentEntries.length === 0) {
            container.innerHTML = `
                <div class="empty-state">
                    <div class="empty-state-icon">📝</div>
                    <div class="empty-state-text">Keine Einträge vorhanden</div>
                    <div class="empty-state-subtext">Fange an, deinen Tee-Konsum zu tracken!</div>
                </div>
            `;
            return;
        }
        
        container.innerHTML = recentEntries.map(entry => {
            const tea = this.getTeaById(entry.teaId);
            const date = new Date(entry.date);
            const formattedDate = date.toLocaleDateString('de-DE');
            const formattedTime = entry.time ? entry.time.substring(0, 5) : '';
            
            return `
                <div class="activity-item">
                    <div class="activity-info">
                        <div class="activity-tea">${tea ? tea.name : 'Unbekannter Tee'} ${tea && tea.organic ? '<span class="organic-badge" title="Bio-Tee">🌱</span>' : ''}</div>
                        <div class="activity-details">${formattedDate} ${formattedTime ? `um ${formattedTime}` : ''}</div>
                    </div>
                    <div class="activity-amount">${entry.amount} Tasse${entry.amount > 1 ? 'n' : ''}</div>
                </div>
            `;
        }).join('');
    }
    
    openTeaModal(teaId = null) {
        const modal = document.getElementById('tea-modal');
        const form = document.getElementById('tea-form');
        const deleteBtn = document.getElementById('delete-tea-btn');
        
        if (teaId) {
            const tea = this.getTeaById(teaId);
            if (tea) {
                document.getElementById('modal-title').textContent = 'Tee bearbeiten';
                document.getElementById('tea-id').value = tea.id;
                document.getElementById('tea-name').value = tea.name;
                document.getElementById('tea-type').value = tea.type;
                document.getElementById('tea-brand').value = tea.brand || '';
                document.getElementById('tea-description').value = tea.description || '';
                document.getElementById('tea-color').value = tea.color || '#8B4513';
                document.getElementById('tea-organic').checked = tea.organic || false;
                deleteBtn.style.display = 'inline-flex';
                this.currentTeaId = tea.id;
            }
        } else {
            document.getElementById('modal-title').textContent = 'Tee hinzufügen';
            form.reset();
            document.getElementById('tea-id').value = '';
            deleteBtn.style.display = 'none';
            this.currentTeaId = null;
        }
        
        modal.classList.add('active');
    }
    
    closeTeaModal() {
        document.getElementById('tea-modal').classList.remove('active');
        document.getElementById('tea-form').reset();
        this.currentTeaId = null;
    }
    
    handleTeaFormSubmit(e) {
        e.preventDefault();
        
        const formData = {
            name: document.getElementById('tea-name').value.trim(),
            type: document.getElementById('tea-type').value,
            brand: document.getElementById('tea-brand').value.trim(),
            description: document.getElementById('tea-description').value.trim(),
            color: document.getElementById('tea-color').value,
            organic: document.getElementById('tea-organic').checked
        };
        
        const teaId = document.getElementById('tea-id').value;
        
        if (teaId) {
            // Update existing tea
            this.updateTea(teaId, formData);
            this.showToast('Tee erfolgreich aktualisiert!', 'success');
        } else {
            // Add new tea
            this.addTea(formData);
            this.showToast('Tee erfolgreich hinzugefügt!', 'success');
        }
        
        this.closeTeaModal();
        this.renderTeasList();
        this.renderTrackForm();
        this.updateDashboard();
        this.updateStats();
    }
    
    editTea(teaId) {
        this.openTeaModal(teaId);
    }
    
    showDeleteTeaConfirm(teaId) {
        this.currentTeaId = teaId;
        const tea = this.getTeaById(teaId);
        document.getElementById('confirm-message').textContent = 
            `Möchtest du den Tee "${tea.name}" wirklich löschen? Alle zugehörigen Einträge werden ebenfalls gelöscht.`;
        document.getElementById('confirm-modal').classList.add('active');
    }
    
    handleDeleteTea() {
        if (this.currentTeaId) {
            const tea = this.getTeaById(this.currentTeaId);
            if (tea) {
                document.getElementById('confirm-message').textContent = 
                    `Möchtest du den Tee "${tea.name}" wirklich löschen? Alle zugehörigen Einträge werden ebenfalls gelöscht.`;
                document.getElementById('confirm-modal').classList.add('active');
            }
        }
    }
    
    confirmDelete() {
        if (this.currentTeaId) {
            const tea = this.getTeaById(this.currentTeaId);
            if (tea) {
                this.deleteTea(this.currentTeaId);
                this.showToast(`Tee "${tea.name}" wurde gelöscht.`, 'success');
                this.closeConfirmModal();
                this.closeTeaModal();
                this.renderTeasList();
                this.renderTrackForm();
                this.updateDashboard();
                this.updateStats();
            }
        }
    }
    
    closeConfirmModal() {
        document.getElementById('confirm-modal').classList.remove('active');
        this.currentTeaId = null;
    }
    
    // ============================================
    // Track Form
    // ============================================
    
    renderTrackForm() {
        const teaSelect = document.getElementById('track-tea');
        const today = new Date().toISOString().split('T')[0];
        
        // Set default date to today
        document.getElementById('track-date').value = today;
        
        // Populate tea dropdown
        if (this.teas.length === 0) {
            teaSelect.innerHTML = '<option value="">-- Keine Tee-Sorten verfügbar --</option>';
        } else {
            teaSelect.innerHTML = '<option value="">-- Wähle eine Tee-Sorte --</option>' +
                this.teas.map(tea => 
                    `<option value="${tea.id}">${tea.name} (${tea.type})${tea.organic ? ' 🌱' : ''}</option>`
                ).join('');
        }
        
        // Render recent entries
        this.renderTrackRecentEntries();
    }
    
    handleTrackFormSubmit(e) {
        e.preventDefault();
        
        const teaId = document.getElementById('track-tea').value;
        const date = document.getElementById('track-date').value;
        const time = document.getElementById('track-time').value;
        const amount = document.getElementById('track-amount').value;
        const notes = document.getElementById('track-notes').value.trim();
        
        if (!teaId || !date || !amount) {
            this.showToast('Bitte fülle alle Pflichtfelder aus!', 'error');
            return;
        }
        
        const entry = {
            teaId,
            date,
            time,
            amount,
            notes
        };
        
        this.addEntry(entry);
        this.showToast('Tee-Konsum erfolgreich getrackt!', 'success');
        
        // Reset form
        this.resetTrackForm();
        
        // Update UI
        this.updateDashboard();
        this.updateStats();
        this.renderTrackRecentEntries();
    }
    
    resetTrackForm() {
        const form = document.getElementById('track-form');
        form.reset();
        const today = new Date().toISOString().split('T')[0];
        document.getElementById('track-date').value = today;
        document.getElementById('track-amount').value = 1;
    }
    
    // ============================================
    // Statistics
    // ============================================
    
    initCharts() {
        // Initialize Chart.js
        this.createTeaTypeChart();
        this.createDailyChart();
    }
    
    createTeaTypeChart() {
        const ctx = document.getElementById('tea-type-chart');
        if (!ctx) return;
        
        const period = document.getElementById('stats-period').value || 'week';
        const typeCounts = this.getCupsByTeaType(period);
        
        const labels = Object.keys(typeCounts);
        const data = Object.values(typeCounts);
        
        const backgroundColors = labels.map((type, index) => {
            const colors = [
                '#8B4513', '#228B22', '#90EE90', '#FFD700', 
                '#FF6347', '#FF69B4', '#4169E1', '#8A2BE2'
            ];
            return colors[index % colors.length];
        });
        
        if (this.charts.teaType) {
            this.charts.teaType.destroy();
        }
        
        this.charts.teaType = new Chart(ctx, {
            type: 'doughnut',
            data: {
                labels: labels,
                datasets: [{
                    data: data,
                    backgroundColor: backgroundColors,
                    borderWidth: 2,
                    borderColor: '#fff'
                }]
            },
            options: {
                responsive: true,
                maintainAspectRatio: false,
                plugins: {
                    legend: {
                        position: 'right',
                        labels: {
                            padding: 15,
                            font: {
                                size: 12
                            }
                        }
                    },
                    tooltip: {
                        callbacks: {
                            label: function(context) {
                                const label = context.label || '';
                                const value = context.raw || 0;
                                return `${label}: ${value} Tasse${value > 1 ? 'n' : ''}`;
                            }
                        }
                    }
                },
                layout: {
                    padding: 20
                }
            }
        });
    }
    
    createDailyChart() {
        const ctx = document.getElementById('daily-chart');
        if (!ctx) return;
        
        const period = document.getElementById('stats-period').value || 'week';
        const dailyCounts = this.getDailyConsumption(period);
        
        // Sort dates chronologically
        const sortedDates = Object.keys(dailyCounts).sort();
        const labels = sortedDates.map(date => {
            const d = new Date(date);
            return period === 'year' ? d.toLocaleDateString('de-DE', { month: 'short', day: 'numeric' }) : d.toLocaleDateString('de-DE', { weekday: 'short', day: 'numeric' });
        });
        const data = sortedDates.map(date => dailyCounts[date]);
        
        if (this.charts.daily) {
            this.charts.daily.destroy();
        }
        
        this.charts.daily = new Chart(ctx, {
            type: 'bar',
            data: {
                labels: labels,
                datasets: [{
                    label: 'Tassen pro Tag',
                    data: data,
                    backgroundColor: 'rgba(139, 69, 19, 0.7)',
                    borderColor: 'rgba(139, 69, 19, 1)',
                    borderWidth: 2
                }]
            },
            options: {
                responsive: true,
                maintainAspectRatio: false,
                plugins: {
                    legend: {
                        display: false
                    },
                    tooltip: {
                        callbacks: {
                            label: function(context) {
                                return `${context.raw} Tasse${context.raw > 1 ? 'n' : ''}`;
                            }
                        }
                    }
                },
                scales: {
                    y: {
                        beginAtZero: true,
                        ticks: {
                            stepSize: 1,
                            callback: function(value) {
                                return value + (value === 1 ? ' Tasse' : ' Tassen');
                            }
                        }
                    }
                },
                layout: {
                    padding: 20
                }
            }
        });
    }
    
    updateStats() {
        const period = document.getElementById('stats-period').value || 'week';
        
        // Update charts
        this.createTeaTypeChart();
        this.createDailyChart();
        
        // Update detailed stats
        this.renderDetailedStats(period);
    }
    
    renderDetailedStats(period) {
        const container = document.getElementById('stats-details');
        const entries = this.getEntriesByPeriod(period);
        const totalCups = entries.reduce((sum, entry) => sum + entry.amount, 0);
        const uniqueDays = this.countUniqueDays(entries);
        const avgDaily = uniqueDays > 0 ? Math.round(totalCups / uniqueDays) : 0;
        const mostConsumed = this.getMostConsumedTea(period);
        const teaCount = new Set(entries.map(entry => entry.teaId)).size;
        
        container.innerHTML = `
            <div class="detail-item">
                <div class="detail-item-label">Gesamt getrunken</div>
                <div class="detail-item-value">${totalCups} Tassen</div>
            </div>
            <div class="detail-item">
                <div class="detail-item-label">Durchschnitt pro Tag</div>
                <div class="detail-item-value">${avgDaily} Tassen</div>
            </div>
            <div class="detail-item">
                <div class="detail-item-label">Aktive Tage</div>
                <div class="detail-item-value">${uniqueDays} Tage</div>
            </div>
            <div class="detail-item">
                <div class="detail-item-label">Verschiedene Tees</div>
                <div class="detail-item-value">${teaCount} Sorten</div>
            </div>
            ${mostConsumed.name ? `
            <div class="detail-item">
                <div class="detail-item-label">Meist getrunken</div>
                <div class="detail-item-value">${mostConsumed.name}</div>
            </div>
            <div class="detail-item">
                <div class="detail-item-label">Favorit (Anzahl)</div>
                <div class="detail-item-value">${mostConsumed.count} Tassen</div>
            </div>
            ` : ''}
        `;
    }
    
    // ============================================
    // Utility Functions
    // ============================================
    
    showToast(message, type = 'info') {
        // Remove existing toasts
        const existingToast = document.querySelector('.toast');
        if (existingToast) {
            existingToast.remove();
        }
        
        const toast = document.createElement('div');
        toast.className = `toast ${type}`;
        toast.textContent = message;
        document.body.appendChild(toast);
        
        setTimeout(() => {
            toast.style.animation = 'toastSlideIn 0.3s ease reverse';
            setTimeout(() => toast.remove(), 300);
        }, 3000);
    }
}

// Initialize the application
let app;
document.addEventListener('DOMContentLoaded', () => {
    app = new TeaTracker();
    window.app = app;
});