// API Communication and State Sync
const API = {
    tokenKey: 'el_puro_jwt_token',
    userKey: 'el_puro_username',

    getToken() {
        return localStorage.getItem(this.tokenKey);
    },

    getUsername() {
        return localStorage.getItem(this.userKey);
    },

    setAuth(token, username) {
        localStorage.setItem(this.tokenKey, token);
        localStorage.setItem(this.userKey, username);
    },

    logout() {
        localStorage.removeItem(this.tokenKey);
        localStorage.removeItem(this.userKey);
    },

    async register(username, password, websiteHp = '') {
        const res = await fetch('/api/auth/register', {
            method: 'POST',
            headers: { 'Content-Type': 'application/json' },
            body: JSON.stringify({
                username,
                password,
                website_hp: websiteHp
            })
        });
        if (!res.ok) {
            const err = await res.json().catch(() => ({ detail: 'Registration failed' }));
            throw new Error(err.detail || 'Registration failed');
        }
        const data = await res.json();
        this.setAuth(data.token, data.username);
        return data;
    },

    async login(username, password) {
        const res = await fetch('/api/auth/login', {
            method: 'POST',
            headers: { 'Content-Type': 'application/json' },
            body: JSON.stringify({ username, password })
        });
        if (!res.ok) {
            const err = await res.json().catch(() => ({ detail: 'Invalid credentials' }));
            throw new Error(err.detail || 'Login failed');
        }
        const data = await res.json();
        this.setAuth(data.token, data.username);
        return data;
    },

    async loadRemoteSave() {
        const token = this.getToken();
        if (!token) return null;

        try {
            const res = await fetch('/api/game/state', {
                headers: { 'Authorization': `Bearer ${token}` }
            });
            if (!res.ok) {
                if (res.status === 401) this.logout();
                return null;
            }
            const data = await res.json();
            return data.has_save ? data.save_data : null;
        } catch (e) {
            console.warn('Network issue loading cloud save, fallback to local', e);
            return null;
        }
    },

    async syncTick(actions = []) {
        const token = this.getToken();
        if (!token) return null;

        try {
            const res = await fetch('/api/game/tick', {
                method: 'POST',
                headers: {
                    'Content-Type': 'application/json',
                    'Authorization': `Bearer ${token}`
                },
                body: JSON.stringify({ actions })
            });
            if (!res.ok) {
                if (res.status === 401) this.logout();
                return null;
            }
            const data = await res.json();
            return data.save_data;
        } catch (e) {
            console.warn('Network tick failed, queuing actions', e);
            return null;
        }
    },

    async saveRemote(saveData) {
        const token = this.getToken();
        if (!token) return;

        try {
            await fetch('/api/game/save', {
                method: 'POST',
                headers: {
                    'Content-Type': 'application/json',
                    'Authorization': `Bearer ${token}`
                },
                body: JSON.stringify({ save_data: saveData })
            });
        } catch (e) {
            console.warn('Failed cloud save sync', e);
        }
    }
};