/**
 * Cosmic Garden - Main Game Engine
 * Handles game state, tick loop, and core logic
 */

const Game = {
    // Core game state
    state: {
        stardust: 0,
        totalStardust: 0,
        totalClicks: 0,
        clickPower: 1,
        startTime: Date.now(),
        lastSaveTime: Date.now(),
        buildings: {},
        upgrades: [],
        achievements: []
    },

    // Configuration
    config: {
        tickRate: 100, // ms per tick (10 ticks/sec)
        autoSaveInterval: 30000, // 30 seconds
        costScaling: 1.15 // Cost multiplier per building level
    },

    /**
     * Initialize the game
     */
    init() {
        this.loadState();
        this.setupEventListeners();
        this.startGameLoop();
        this.startAutoSave();
        Audio.init();
        UI.init();
        Stats.init();
        console.log('🌌 Cosmic Garden initialized!');
    },

    /**
     * Setup event listeners
     */
    setupEventListeners() {
        // Harvest button
        document.getElementById('harvest-btn').addEventListener('click', (e) => {
            this.harvest(e);
        });

        // Save buttons
        document.getElementById('save-btn').addEventListener('click', () => {
            this.save();
            UI.showNotification('Game saved!', 'success');
        });

        document.getElementById('export-btn').addEventListener('click', () => {
            SaveSystem.exportSave();
        });

        document.getElementById('import-btn').addEventListener('click', () => {
            UI.showImportModal();
        });

        document.getElementById('confirm-import').addEventListener('click', () => {
            const data = document.getElementById('import-data').value;
            if (data) {
                this.loadFromData(data);
                UI.hideImportModal();
                UI.showNotification('Save imported!', 'success');
            }
        });

        document.getElementById('cancel-import').addEventListener('click', () => {
            UI.hideImportModal();
        });

        document.getElementById('reset-btn').addEventListener('click', () => {
            if (confirm('Are you sure you want to reset all progress? This cannot be undone!')) {
                this.reset();
            }
        });

        // Tab switching
        document.querySelectorAll('.tab-btn').forEach(btn => {
            btn.addEventListener('click', (e) => {
                const tab = e.target.dataset.tab;
                document.querySelectorAll('.tab-btn').forEach(b => b.classList.remove('active'));
                document.querySelectorAll('.tab-content').forEach(c => c.classList.remove('active'));
                e.target.classList.add('active');
                document.getElementById(`${tab}-tab`).classList.add('active');
            });
        });
    },

    /**
     * Harvest stardust by clicking
     */
    harvest(event) {
        const amount = this.getClickPower();
        this.addStardust(amount);
        this.state.totalClicks++;

        // Audio feedback
        Audio.playClick();

        // Visual feedback
        UI.showFloatingText(event.clientX, event.clientY, `+${this.formatNumber(amount)}`);
        Particles.createClickParticles(event.clientX, event.clientY, 8);
        UI.update();
    },

    /**
     * Add stardust to the game
     */
    addStardust(amount) {
        this.state.stardust += amount;
        this.state.totalStardust += amount;
    },

    /**
     * Get current click power
     */
    getClickPower() {
        let power = 1;
        
        // Apply upgrade bonuses
        for (const upgradeId of this.state.upgrades) {
            const upgrade = UPGRADES[upgradeId];
            if (upgrade && upgrade.clickPowerBonus) {
                power *= upgrade.clickPowerBonus;
            }
        }
        
        return Math.floor(power);
    },

    /**
     * Calculate production per second
     */
    getProductionPerSecond() {
        let total = 0;
        
        for (const [buildingId, count] of Object.entries(this.state.buildings)) {
            if (count === 0) continue;
            
            const building = BUILDINGS[buildingId];
            if (!building) continue;
            
            let production = building.baseProduction * count;
            
            // Apply upgrade bonuses
            for (const upgradeId of this.state.upgrades) {
                const upgrade = UPGRADES[upgradeId];
                if (upgrade && upgrade.buildingBonus && upgrade.buildingBonus[buildingId]) {
                    production *= upgrade.buildingBonus[buildingId];
                }
                if (upgrade && upgrade.globalBonus) {
                    production *= upgrade.globalBonus;
                }
            }
            
            total += production;
        }
        
        return total;
    },

    /**
     * Get building cost
     */
    getBuildingCost(buildingId) {
        const building = BUILDINGS[buildingId];
        const count = this.state.buildings[buildingId] || 0;
        return Math.floor(building.baseCost * Math.pow(this.config.costScaling, count));
    },

    /**
     * Buy a building
     */
    buyBuilding(buildingId) {
        const cost = this.getBuildingCost(buildingId);
        
        if (this.state.stardust >= cost) {
            this.state.stardust -= cost;
            this.state.buildings[buildingId] = (this.state.buildings[buildingId] || 0) + 1;
            
            UI.showNotification(`Bought ${BUILDINGS[buildingId].name}!`, 'success');

            // Audio feedback
            Audio.playPurchase();

            // Particle effect on building purchase
            const card = document.getElementById(`building-${buildingId}`);
            if (card) {
                const rect = card.getBoundingClientRect();
                Particles.createBuildingEffect(rect.left + rect.width / 2, rect.top + rect.height / 2);
            }
            
            UI.update();
            return true;
        }
        
        return false;
    },

    /**
     * Buy an upgrade
     */
    buyUpgrade(upgradeId) {
        const upgrade = UPGRADES[upgradeId];
        if (!upgrade || this.state.upgrades.includes(upgradeId)) {
            return false;
        }
        
        if (this.state.stardust >= upgrade.cost) {
            // Check requirements
            if (upgrade.requirements) {
                for (const [reqId, reqCount] of Object.entries(upgrade.requirements)) {
                    const currentCount = this.state.buildings[reqId] || 0;
                    if (currentCount < reqCount) {
                        UI.showNotification('Requirements not met!', 'warning');
                        return false;
                    }
                }
            }
            
            this.state.stardust -= upgrade.cost;
            this.state.upgrades.push(upgradeId);
            
            UI.showNotification(`Unlocked: ${upgrade.name}!`, 'success');
            UI.update();
            return true;
        }
        
        return false;
    },

    /**
     * Game tick - called every config.tickRate ms
     */
    tick() {
        const production = this.getProductionPerSecond();
        const tickSeconds = this.config.tickRate / 1000;
        
        if (production > 0) {
            this.addStardust(production * tickSeconds);
        }
        
        UI.update();
        Achievements.check();
    },

    /**
     * Start the game loop
     */
    startGameLoop() {
        setInterval(() => this.tick(), this.config.tickRate);
    },

    /**
     * Start auto-save
     */
    startAutoSave() {
        setInterval(() => {
            this.save();
            document.getElementById('last-saved').textContent = 
                `Last saved: ${new Date().toLocaleTimeString()}`;
        }, this.config.autoSaveInterval);
    },

    /**
     * Save game state
     */
    save() {
        this.state.lastSaveTime = Date.now();
        localStorage.setItem('cosmicGardenSave', JSON.stringify(this.state));
    },

    /**
     * Load game state
     */
    loadState() {
        const saved = localStorage.getItem('cosmicGardenSave');
        if (saved) {
            try {
                const parsed = JSON.parse(saved);
                this.state = { ...this.state, ...parsed };
                
                // Calculate offline progress
                const offlineTime = (Date.now() - this.state.lastSaveTime) / 1000;
                if (offlineTime > 60) {
                    const production = this.getProductionPerSecond();
                    const offlineEarnings = production * offlineTime * 0.5; // 50% offline efficiency
                    if (offlineEarnings > 0) {
                        this.addStardust(offlineEarnings);
                        UI.showNotification(
                            `Welcome back! Earned ${this.formatNumber(offlineEarnings)} ✨ while away`,
                            'success'
                        );
                    }
                }
            } catch (e) {
                console.error('Failed to load save:', e);
            }
        }
    },

    /**
     * Load from imported data
     */
    loadFromData(data) {
        try {
            const parsed = JSON.parse(atob(data));
            this.state = { ...this.state, ...parsed };
            UI.update();
        } catch (e) {
            UI.showNotification('Invalid save data!', 'warning');
        }
    },

    /**
     * Export save as base64
     */
    exportSave() {
        this.save();
        const data = btoa(JSON.stringify(this.state));
        navigator.clipboard.writeText(data).then(() => {
            UI.showNotification('Save copied to clipboard!', 'success');
        });
    },

    /**
     * Reset game
     */
    reset() {
        localStorage.removeItem('cosmicGardenSave');
        this.state = {
            stardust: 0,
            totalStardust: 0,
            totalClicks: 0,
            clickPower: 1,
            startTime: Date.now(),
            lastSaveTime: Date.now(),
            buildings: {},
            upgrades: [],
            achievements: []
        };
        UI.update();
        UI.showNotification('Game reset!', 'warning');
    },

    /**
     * Format numbers with commas
     */
    formatNumber(num) {
        if (num >= 1e12) return (num / 1e12).toFixed(2) + 'T';
        if (num >= 1e9) return (num / 1e9).toFixed(2) + 'B';
        if (num >= 1e6) return (num / 1e6).toFixed(2) + 'M';
        if (num >= 1e3) return (num / 1e3).toFixed(2) + 'K';
        return Math.floor(num).toLocaleString();
    }
};

// Make Game globally accessible
window.Game = Game;