/**
 * weather.js - A module for weather-related functionality
 * Provides real-time weather data and sunset/sunrise information
 * Uses OpenWeatherMap API for weather data
 */

class WeatherManager {
    constructor(options = {}) {
        // Default options
        // Get API key from options, window (injected by server from .env), or fallback
        const apiKey = options.apiKey || window.OPENWEATHERMAP_API_KEY || '';
        
        this.options = {
            latitude: options.latitude || (window.DEFAULT_LOCATION?.latitude) || 59.3293, // Stockholm latitude
            longitude: options.longitude || (window.DEFAULT_LOCATION?.longitude) || 18.0686, // Stockholm longitude
            apiKey: apiKey, // OpenWeatherMap API key (from .env via server injection, or fallback)
            refreshInterval: options.refreshInterval || 30 * 60 * 1000, // 30 minutes in milliseconds
            ...options
        };
        
        // State
        this.weatherData = null;
        this.forecastData = null;
        this.sunTimes = null;
        this.isDarkMode = false;
        this.lastUpdated = null;
        this.daylightBarUpdateInterval = null;
        
        // Initialize
        this.init();
    }
    
    /**
     * Initialize the weather manager
     */
    async init() {
        try {
            // Check for API key
            if (!this.options.apiKey) {
                console.warn('WeatherManager: No OpenWeatherMap API key configured. Set OPENWEATHERMAP_API_KEY in your .env file.');
                const weatherContainer = document.getElementById('custom-weather');
                if (weatherContainer) {
                    const warningEl = document.createElement('div');
                    warningEl.style.cssText = 'padding: 10px; color: #c41e3a; font-size: 0.9em; text-align: center;';
                    warningEl.textContent = 'Weather unavailable: No API key configured. Set OPENWEATHERMAP_API_KEY in .env';
                    weatherContainer.prepend(warningEl);
                }
                // Still set up sun times from calculation so dark mode works
                await this.updateSunTimesFromCalculation();
                this.updateDarkModeBasedOnTime();
                this.dispatchDarkModeEvent();
                return;
            }

            // Fetch weather data
            await this.fetchWeatherData();
            
            // Check if it's dark outside (only affects auto mode)
            this.updateDarkModeBasedOnTime();
            
            // Set up interval to check dark mode every minute (only affects auto mode)
            this.darkModeCheckInterval = setInterval(() => {
                // Only update dark mode based on time if ConfigManager has dark mode set to 'auto'
                if (this.shouldUseAutoDarkMode()) {
                    this.updateDarkModeBasedOnTime();
                }
            }, 60000);
            
            // Set up interval to refresh weather data
            setInterval(() => this.fetchWeatherData(), this.options.refreshInterval);
            
            // Dispatch initial dark mode state
            this.dispatchDarkModeEvent();
            
            console.log('WeatherManager initialized');
        } catch (error) {
            console.error('Error initializing WeatherManager:', error);
            
            // Fallback to calculated sun times if API fails
            await this.updateSunTimesFromCalculation();
            this.updateDarkModeBasedOnTime();
            this.dispatchDarkModeEvent();
        }
    }
    
    /**
     * Check if we should use automatic dark mode based on ConfigManager settings
     */
    shouldUseAutoDarkMode() {
        // If there's a ConfigManager instance with a config
        if (window.configManager && window.configManager.config) {
            // Only use auto dark mode if the setting is 'auto'
            return window.configManager.config.darkMode === 'auto';
        }
        // Default to true if no ConfigManager is available
        return true;
    }
    
    /**
     * Fetch weather data from OpenWeatherMap API
     */
    async fetchWeatherData() {
        try {
            // Fetch current weather (lang=se for Swedish descriptions)
            const currentWeatherUrl = `https://api.openweathermap.org/data/2.5/weather?lat=${this.options.latitude}&lon=${this.options.longitude}&units=metric&lang=se&appid=${this.options.apiKey}`;
            const currentWeatherResponse = await fetch(currentWeatherUrl);
            const currentWeatherData = await currentWeatherResponse.json();

            if (currentWeatherData.cod !== 200) {
                throw new Error(`API Error: ${currentWeatherData.message}`);
            }

            // Fetch 3-hour interval forecast (cnt=8 limits to ~24h of data)
            const forecastUrl = `https://api.openweathermap.org/data/2.5/forecast?lat=${this.options.latitude}&lon=${this.options.longitude}&units=metric&lang=se&cnt=8&appid=${this.options.apiKey}`;
            const forecastResponse = await fetch(forecastUrl);
            const forecastData = await forecastResponse.json();
            
            if (forecastData.cod !== "200") {
                throw new Error(`API Error: ${forecastData.message}`);
            }
            
            // Process and store the data
            this.weatherData = this.processCurrentWeather(currentWeatherData);
            this.forecastData = this.processForecast(forecastData);
            this.lastUpdated = new Date();
            
            // Extract sunrise and sunset times from the API response
            await this.updateSunTimesFromApi(currentWeatherData);
            
            // Update the UI with the new data
            this.updateWeatherUI();
            
            console.log('Weather data updated:', this.weatherData);
            return this.weatherData;
        } catch (error) {
            console.error('Error fetching weather data:', error);
            
            // If we don't have any weather data yet, create some default data
            if (!this.weatherData) {
                this.weatherData = this.createDefaultWeatherData();
                this.forecastData = this.createDefaultForecastData();
            }
            
            // Fallback to calculated sun times
            await this.updateSunTimesFromCalculation();
            
            return this.weatherData;
        }
    }
    
    /**
     * Process current weather data from API response
     */
    processCurrentWeather(data) {
        const iconCode = data.weather[0].icon;
        return {
            temperature: Math.round(data.main.temp * 10) / 10, // Round to 1 decimal place
            condition: data.weather[0].main,
            description: data.weather[0].description,
            icon: this.getWeatherIconUrl(iconCode),
            iconCode: iconCode, // Store icon code for classification
            wind: {
                speed: Math.round(data.wind.speed * 3.6), // Convert m/s to km/h
                direction: data.wind.deg
            },
            humidity: data.main.humidity,
            pressure: data.main.pressure,
            precipitation: data.rain ? (data.rain['1h'] || 0) : 0,
            location: data.name,
            country: data.sys.country,
            timestamp: new Date(data.dt * 1000)
        };
    }
    
    /**
     * Process forecast data from API response
     */
    processForecast(data) {
        // Get the next 7 forecast periods (3-hour intervals, covering ~21 hours)
        return data.list.slice(0, 7).map(item => {
            const iconCode = item.weather[0].icon;
            return {
                temperature: Math.round(item.main.temp * 10) / 10,
                condition: item.weather[0].main,
                description: item.weather[0].description,
                icon: this.getWeatherIconUrl(iconCode),
                iconCode: iconCode, // Store icon code for classification
                timestamp: new Date(item.dt * 1000),
                precipitation: item.rain ? (item.rain['3h'] || 0) : 0
            };
        });
    }
    
    /**
     * Get weather icon URL from icon code
     */
    getWeatherIconUrl(iconCode) {
        return `https://openweathermap.org/img/wn/${iconCode}@4x.png`;
    }
    
    /**
     * Classify a weather icon and return the appropriate CSS classes
     * @param {string} iconCode - OWM icon code (e.g. '01d', '13n')
     * @param {string} condition - Weather condition text (e.g. 'Clear', 'Clouds')
     * @returns {string[]} Array of CSS class names to apply
     */
    classifyWeatherIcon(iconCode, condition) {
        const code = iconCode ? iconCode.replace(/[dn]$/, '') : '';

        // Snow: icon 13x or condition contains 'Snow'
        if (code === '13' || condition.includes('Snow')) {
            return ['weather-snow'];
        }
        // Clear sun: icon 01x or condition is exactly 'Clear'
        if (code === '01' || condition === 'Clear') {
            return ['weather-sun', 'weather-clear-sun'];
        }
        // Sun behind clouds: icon 02-04x or cloudy condition
        if (['02', '03', '04'].includes(code) || (condition.includes('Clouds') && !condition.includes('Clear'))) {
            return ['weather-sun', 'weather-clouds-sun'];
        }
        return [];
    }

    /**
     * Apply weather icon CSS classes to an element
     */
    applyWeatherIconClasses(element, iconCode, condition) {
        element.classList.remove('weather-sun', 'weather-snow', 'weather-clear-sun', 'weather-clouds-sun');
        const classes = this.classifyWeatherIcon(iconCode, condition);
        if (classes.length > 0) {
            element.classList.add(...classes);
        }
    }
    
    /**
     * Create default weather data for fallback
     */
    createDefaultWeatherData() {
        return {
            temperature: 7.1,
            condition: 'Clear',
            description: 'clear sky',
            icon: 'https://openweathermap.org/img/wn/01d@4x.png',
            iconCode: '01d',
            wind: {
                speed: 14.8,
                direction: 270
            },
            humidity: 65,
            pressure: 1012.0,
            precipitation: 0.00,
            location: 'Stockholm',
            country: 'SE',
            timestamp: new Date()
        };
    }
    
    /**
     * Create default forecast data for fallback
     */
    createDefaultForecastData() {
        const now = new Date();
        const forecasts = [];
        
        // Create 7 forecast entries
        for (let i = 0; i < 7; i++) {
            const forecastTime = new Date(now);
            forecastTime.setHours(now.getHours() + i);
            
            forecasts.push({
                temperature: 7.1 - (i * 0.3), // Decrease temperature slightly each hour
                condition: i < 2 ? 'Clear' : 'Clouds',
                description: i < 2 ? 'clear sky' : 'few clouds',
                icon: i < 2 ? 'https://openweathermap.org/img/wn/01n@4x.png' : 'https://openweathermap.org/img/wn/02n@4x.png',
                iconCode: i < 2 ? '01n' : '02n',
                timestamp: forecastTime,
                precipitation: 0
            });
        }
        
        return forecasts;
    }
    
    /**
     * Update the weather UI with current data
     */
    updateWeatherUI() {
        if (!this.weatherData || !this.forecastData) return;
        
        try {
            // Update current weather
            const locationElement = document.querySelector('#custom-weather h3');
            if (locationElement) {
                locationElement.textContent = this.weatherData.location;
            }
            
            const conditionElement = document.querySelector('#custom-weather .weather-icon div');
            if (conditionElement) {
                conditionElement.textContent = this.weatherData.condition;
            }
            
            const iconElement = document.querySelector('#custom-weather .weather-icon img');
            if (iconElement) {
                iconElement.src = this.weatherData.icon;
                iconElement.alt = this.weatherData.description;
                iconElement.setAttribute('data-condition', this.weatherData.condition);
                this.applyWeatherIconClasses(iconElement, this.weatherData.iconCode, this.weatherData.condition);
            }
            
            const temperatureElement = document.querySelector('#custom-weather .temperature');
            if (temperatureElement) {
                temperatureElement.textContent = `${this.weatherData.temperature} °C`;
            }
            
            // Update forecast
            const forecastContainer = document.querySelector('#custom-weather .forecast');
            if (forecastContainer) {
                // Clear existing forecast
                forecastContainer.innerHTML = '';
                
                // Add current weather as "Nu" (Swedish for "Now")
                const nowElement = document.createElement('div');
                nowElement.className = 'forecast-hour';
                const nowIcon = document.createElement('img');
                nowIcon.src = this.weatherData.icon;
                nowIcon.alt = this.weatherData.description;
                nowIcon.width = 56;
                nowIcon.setAttribute('data-condition', this.weatherData.condition);
                this.applyWeatherIconClasses(nowIcon, this.weatherData.iconCode, this.weatherData.condition);
                nowElement.innerHTML = `
                    <div class="time">Nu</div>
                    <div class="icon"></div>
                    <div class="temp">${this.weatherData.temperature} °C</div>
                `;
                nowElement.querySelector('.icon').appendChild(nowIcon);
                forecastContainer.appendChild(nowElement);
                
                // Add hourly forecasts
                this.forecastData.forEach(forecast => {
                    const forecastTime = forecast.timestamp;
                    const timeString = forecastTime.toLocaleTimeString('sv-SE', { hour: '2-digit', minute: '2-digit' });
                    
                    const forecastElement = document.createElement('div');
                    forecastElement.className = 'forecast-hour';
                    const forecastIcon = document.createElement('img');
                    forecastIcon.src = forecast.icon;
                    forecastIcon.alt = forecast.description;
                    forecastIcon.width = 56;
                    forecastIcon.setAttribute('data-condition', forecast.condition);
                    this.applyWeatherIconClasses(forecastIcon, forecast.iconCode, forecast.condition);
                    forecastElement.innerHTML = `
                        <div class="time">${timeString}</div>
                        <div class="icon"></div>
                        <div class="temp">${forecast.temperature} °C</div>
                    `;
                    forecastElement.querySelector('.icon').appendChild(forecastIcon);
                    forecastContainer.appendChild(forecastElement);
                });
            }
            
            // Update sun times
            const sunTimesElement = document.querySelector('#custom-weather .sun-times');
            if (sunTimesElement && this.sunTimes) {
                const sunriseTime = this.formatTime(this.sunTimes.today.sunrise);
                const sunsetTime = this.formatTime(this.sunTimes.today.sunset);
                sunTimesElement.textContent = `☀️ Sunrise: ${sunriseTime} | 🌙 Sunset: ${sunsetTime}`;
            }
            
            // Update daylight hours bar
            if (this.sunTimes) {
                this.updateDaylightHoursBar();
            }
        } catch (error) {
            console.error('Error updating weather UI:', error);
        }
    }
    
    /**
     * Update sunrise and sunset times from API data
     */
    async updateSunTimesFromApi(data) {
        if (!data || !data.sys || !data.sys.sunrise || !data.sys.sunset) {
            console.warn('No sunrise/sunset data in API response, using calculated times');
            await this.updateSunTimesFromCalculation();
            return;
        }

        try {
            // Create Date objects from Unix timestamps for today
            const sunrise = new Date(data.sys.sunrise * 1000);
            const sunset = new Date(data.sys.sunset * 1000);

            // Fetch tomorrow's times from sunrise-sunset.org API
            const tomorrowTimes = await this.fetchSunTimes('tomorrow');

            this.sunTimes = {
                today: { sunrise, sunset },
                tomorrow: tomorrowTimes
            };

            console.log('Sun times updated from API:', this.sunTimes);
            return this.sunTimes;
        } catch (error) {
            console.error('Error updating sun times from API:', error);
            await this.updateSunTimesFromCalculation();
        }
    }
    
    /**
     * Update sunrise and sunset times using sunrise-sunset.org API
     * Falls back to hardcoded defaults if the API is unreachable
     */
    async updateSunTimesFromCalculation() {
        try {
            const [todayData, tomorrowData] = await Promise.all([
                this.fetchSunTimes('today'),
                this.fetchSunTimes('tomorrow')
            ]);

            this.sunTimes = {
                today: todayData,
                tomorrow: tomorrowData
            };

            console.log('Sun times updated from sunrise-sunset.org:', this.sunTimes);
            return this.sunTimes;
        } catch (error) {
            console.error('Error fetching sun times from API, using defaults:', error);
            const defaultSunrise = new Date();
            defaultSunrise.setHours(7, 0, 0, 0);

            const defaultSunset = new Date();
            defaultSunset.setHours(16, 0, 0, 0);

            this.sunTimes = {
                today: { sunrise: defaultSunrise, sunset: defaultSunset },
                tomorrow: { sunrise: defaultSunrise, sunset: defaultSunset }
            };
            return this.sunTimes;
        }
    }

    /**
     * Fetch sunrise/sunset times from sunrise-sunset.org API
     * @param {string} date - 'today', 'tomorrow', or YYYY-MM-DD
     * @returns {Object} { sunrise: Date, sunset: Date }
     */
    async fetchSunTimes(date) {
        const url = `https://api.sunrise-sunset.org/json?lat=${this.options.latitude}&lng=${this.options.longitude}&date=${date}&formatted=0`;
        const response = await fetch(url);
        const data = await response.json();

        if (data.status !== 'OK') {
            throw new Error(`Sunrise-sunset API returned status: ${data.status}`);
        }

        return {
            sunrise: new Date(data.results.sunrise),
            sunset: new Date(data.results.sunset)
        };
    }
    
    /**
     * Check if it's currently dark outside based on sun times
     */
    isDark() {
        if (!this.sunTimes) return false;
        
        const now = new Date();
        const today = this.sunTimes.today;
        
        // Check if current time is after today's sunset or before today's sunrise
        return now > today.sunset || now < today.sunrise;
    }
    
    /**
     * Update dark mode state based on current time
     */
    updateDarkModeBasedOnTime() {
        const wasDarkMode = this.isDarkMode;
        this.isDarkMode = this.isDark();
        
        // If dark mode state changed, dispatch event
        if (wasDarkMode !== this.isDarkMode) {
            this.dispatchDarkModeEvent();
        }
    }
    
    /**
     * Set dark mode state manually
     */
    setDarkMode(isDarkMode) {
        if (this.isDarkMode !== isDarkMode) {
            this.isDarkMode = isDarkMode;
            this.dispatchDarkModeEvent();
        }
    }
    
    /**
     * Toggle dark mode
     */
    toggleDarkMode() {
        this.isDarkMode = !this.isDarkMode;
        this.dispatchDarkModeEvent();
        return this.isDarkMode;
    }
    
    /**
     * Dispatch dark mode change event
     */
    dispatchDarkModeEvent() {
        const event = new CustomEvent('darkModeChanged', { 
            detail: { 
                isDarkMode: this.isDarkMode,
                automatic: true
            } 
        });
        document.dispatchEvent(event);
        console.log('Dark mode ' + (this.isDarkMode ? 'enabled' : 'disabled'));
    }
    
    /**
     * Get formatted sunrise time
     */
    getSunriseTime() {
        if (!this.sunTimes) return '06:45';
        return this.formatTime(this.sunTimes.today.sunrise);
    }
    
    /**
     * Get formatted sunset time
     */
    getSunsetTime() {
        if (!this.sunTimes) return '17:32';
        return this.formatTime(this.sunTimes.today.sunset);
    }
    
    /**
     * Format time as HH:MM
     */
    formatTime(date) {
        return date.toLocaleTimeString('sv-SE', { hour: '2-digit', minute: '2-digit' });
    }
    
    /**
     * Get the last updated time
     */
    getLastUpdatedTime() {
        if (!this.lastUpdated) return 'Never';
        return this.formatTime(this.lastUpdated);
    }
    
    /**
     * Render the daylight hours bar with gradient and current hour indicator
     */
    renderDaylightHoursBar() {
        if (!this.sunTimes) return;
        
        const barElement = document.getElementById('daylight-hours-bar');
        const backgroundElement = barElement?.querySelector('.daylight-bar-background');
        const indicatorElement = barElement?.querySelector('.daylight-bar-indicator');
        
        if (!barElement || !backgroundElement || !indicatorElement) return;
        
        const today = this.sunTimes.today;
        
        // Normalize sunrise and sunset to today's date for consistent calculation
        const now = new Date();
        const todayDate = new Date(now.getFullYear(), now.getMonth(), now.getDate());
        
        const sunrise = new Date(todayDate);
        sunrise.setHours(today.sunrise.getHours(), today.sunrise.getMinutes(), 0, 0);
        
        const sunset = new Date(todayDate);
        sunset.setHours(today.sunset.getHours(), today.sunset.getMinutes(), 0, 0);
        
        // Calculate positions as percentage of 24 hours (1440 minutes)
        // Extract hours and minutes from the date objects
        const getTimePosition = (date) => {
            const hours = date.getHours();
            const minutes = date.getMinutes();
            const totalMinutes = hours * 60 + minutes;
            return (totalMinutes / 1440) * 100;
        };
        
        const sunrisePosition = getTimePosition(sunrise);
        const sunsetPosition = getTimePosition(sunset);
        const currentPosition = getTimePosition(now);
        
        // Ensure positions are valid (0-100)
        const clampPosition = (pos) => Math.max(0, Math.min(100, pos));
        const sunrisePos = clampPosition(sunrisePosition);
        const sunsetPos = clampPosition(sunsetPosition);
        const currentPos = clampPosition(currentPosition);
        
        // Create modern gradient for daylight hours with smooth transitions
        // Multiple color stops for a more sophisticated gradient effect
        let gradient = '';
        
        // Handle case where sunrise is before sunset (normal day)
        if (sunrisePos < sunsetPos) {
            // Create gradient with smooth transitions:
            // - Midnight blue (night) -> dark blue -> orange/red (dawn) -> yellow (day) -> orange/red (dusk) -> dark blue -> midnight blue (night)
            const dawnStart = Math.max(0, sunrisePos - 2);
            const dawnEnd = Math.min(100, sunrisePos + 1);
            const duskStart = Math.max(0, sunsetPos - 1);
            const duskEnd = Math.min(100, sunsetPos + 2);
            
            gradient = `linear-gradient(to right, 
                #191970 0%, 
                #191970 ${dawnStart}%, 
                #2E3A87 ${dawnStart}%, 
                #FF6B35 ${dawnEnd}%, 
                #FFD93D ${Math.min(100, dawnEnd + 1)}%, 
                #FFEB3B ${Math.min(100, dawnEnd + 1)}%, 
                #FFEB3B ${duskStart}%, 
                #FFD93D ${duskStart}%, 
                #FF6B35 ${Math.max(0, duskEnd - 1)}%, 
                #2E3A87 ${duskEnd}%, 
                #191970 ${duskEnd}%, 
                #191970 100%)`;
        } else {
            // Handle edge cases (polar day/night or sunrise after sunset near midnight)
            // For simplicity, show all as night (midnight blue)
            gradient = 'linear-gradient(to right, #191970 0%, #191970 100%)';
        }
        
        // Apply gradient to background
        backgroundElement.style.backgroundImage = gradient;
        
        // Determine if it's day or night for icon
        const isDaytime = currentPos >= sunrisePos && currentPos <= sunsetPos;
        const iconElement = indicatorElement.querySelector('.sun-icon, .moon-icon');
        if (iconElement) {
            iconElement.textContent = isDaytime ? '☀️' : '🌙';
            
            // Update classes to match the icon for proper styling
            if (isDaytime) {
                iconElement.classList.remove('moon-icon');
                iconElement.classList.add('sun-icon');
            } else {
                iconElement.classList.remove('sun-icon');
                iconElement.classList.add('moon-icon');
            }
        }
        
        // Position current hour indicator
        indicatorElement.style.left = `${currentPos}%`;
        
        // Debug logging
        console.log('Daylight bar positions:', {
            sunrise: `${today.sunrise.getHours()}:${today.sunrise.getMinutes().toString().padStart(2, '0')}`,
            sunset: `${today.sunset.getHours()}:${today.sunset.getMinutes().toString().padStart(2, '0')}`,
            current: `${now.getHours()}:${now.getMinutes().toString().padStart(2, '0')}`,
            sunrisePos: `${sunrisePos.toFixed(1)}%`,
            sunsetPos: `${sunsetPos.toFixed(1)}%`,
            currentPos: `${currentPos.toFixed(1)}%`
        });
    }
    
    /**
     * Update daylight hours bar and set up interval for current hour updates
     */
    updateDaylightHoursBar() {
        // Render the bar immediately
        this.renderDaylightHoursBar();
        
        // Clear existing interval if any
        if (this.daylightBarUpdateInterval) {
            clearInterval(this.daylightBarUpdateInterval);
        }
        
        // Update current hour position every minute
        this.daylightBarUpdateInterval = setInterval(() => {
            this.renderDaylightHoursBar();
        }, 60000); // Update every minute
    }
}

// ES module export
export { WeatherManager };

// Keep window reference for backward compatibility
window.WeatherManager = WeatherManager;