class TutorialModule {
    constructor() {
        this.commands = {};
        this.terminal = null;
        this.STORAGE_KEY = 'webx11_tutorial_state';
        this.COMPLETE_KEY = 'webx11_tutorial_complete';
        this.SKIP_KEY = 'webx11_tutorial_skipped';
        this._maxTries = 3;
        this._initState();
    }

    _initState() {
        // Restore saved state or start fresh
        const saved = localStorage.getItem(this.STORAGE_KEY);
        if (saved) {
            try {
                const s = JSON.parse(saved);
                this._completed = new Set(s.completed || []);
                this._activeIndex = s.activeIndex || 0;
                this._tries = s.tries || {};
                this._started = s.started || false;
                return;
            } catch(e) { /* corrupt, reset */ }
        }
        this._completed = new Set();
        this._activeIndex = 0;
        this._tries = {};
        this._started = false;
    }

    _saveState() {
        try {
            localStorage.setItem(this.STORAGE_KEY, JSON.stringify({
                completed: Array.from(this._completed),
                activeIndex: this._activeIndex,
                tries: this._tries,
                started: this._started
            }));
        } catch(e) { /* quota */ }
    }

    _getQuests() {
        return [
            { id: 1, title: 'Your First Command', desc: 'Type `help` to see every command available in newOS4.',
              check: (cmd) => cmd === 'help', hint: 'Just type: help' },
            { id: 2, title: 'Explore the Filesystem', desc: 'Type `ls` to list files in the current directory.',
              check: (cmd) => cmd === 'ls', hint: 'Type: ls' },
            { id: 3, title: 'Create Something', desc: 'Use `touch hello.txt` to create your first file.',
              check: (cmd) => cmd === 'touch',
              hint: 'Type: touch hello.txt' },
            { id: 4, title: 'Write to a File', desc: 'Open the editor with `edit hello.txt`, type something, and click Save.',
              check: (cmd, term) => { const c = term && term.fs && term.fs.readFile('hello.txt'); return c && c.length > 0; },
              hint: 'Type: edit hello.txt, then write something and click 💾 Save & Test' },
            { id: 5, title: 'Talk to the AI', desc: 'Type `ai "hello"` to greet the AI assistant.',
              check: (cmd) => cmd === 'ai' || cmd === 'ask',
              hint: 'Type: ai "hello"' },
            { id: 6, title: 'Check Your Progress', desc: 'Type `status` to see how the system is doing.',
              check: (cmd) => cmd === 'status',
              hint: 'Type: status' },
        ];
    }

    requirements() {
        return { met: true, missing: [] };
    }

    getHelpInfo() {
        return {
            'tutorial': 'tutorial [start|skip|status] — Interactive guided tour of newOS4 (6 quests)',
        };
    }

    registerCommands() {
        this.commands['tutorial'] = (args) => this._handleTutorial(args);
    }

    // ── Public API called by terminal.js ──

    /** Called after every command execution to check quest progress */
    onCommandExecuted(cmd, args) {
        if (!this._started || this.isComplete()) return;
        const quests = this._getQuests();
        const current = quests[this._activeIndex];
        if (!current || this._completed.has(current.id)) return;

        // Special handling: quest 4 (edit) — don't count as wrong, wait for save
        if (current.id === 4 && cmd === 'edit') {
            this.terminal.print('  ✅ Editor opened! Write something and click Save.', 'success');
            return; // Don't fail, don't complete — wait for onFileSaved
        }

        // Check if this command completes the current quest
        if (current.check(cmd, this.terminal)) {
            this._completeCurrentQuest();
        } else {
            // Wrong command — increment try count
            const count = (this._tries[current.id] || 0) + 1;
            this._tries[current.id] = count;
            this._saveState();
            if (count >= this._maxTries) {
                this.terminal.print(`💡 Hint: ${current.hint}`, 'warning');
                this._tries[current.id] = 0; // reset so hint repeats
            }
        }
    }

    /** Called by editor module after a file is saved via the modal */
    onFileSaved(path) {
        if (!this._started || this.isComplete()) return;
        const quests = this._getQuests();
        const current = quests[this._activeIndex];
        if (!current || current.id !== 4 || this._completed.has(current.id)) return;

        if (current.check('__file_saved__', this.terminal)) {
            this._completeCurrentQuest();
        }
    }

    _completeCurrentQuest() {
        const quests = this._getQuests();
        const current = quests[this._activeIndex];
        this._completed.add(current.id);
        const nextIdx = this._activeIndex + 1;
        const next = quests[nextIdx];
        if (next) {
            this._activeIndex = nextIdx;
            this._saveState();
            this._showQuestNext(next);
        } else {
            this._activeIndex = nextIdx;
            this._saveState();
            this._showCompletion();
        }
    }

    isComplete() {
        return localStorage.getItem(this.COMPLETE_KEY) !== null;
    }

    isSkipped() {
        return localStorage.getItem(this.SKIP_KEY) !== null;
    }

    isStarted() {
        return this._started;
    }

    /** Called by welcome modal to begin the tutorial */
    startTutorial() {
        // Close welcome modal if it's open
        const modal = document.getElementById('welcome-modal');
        if (modal) modal.style.display = 'none';
        
        this._started = true;
        this._completed = new Set();
        this._activeIndex = 0;
        this._tries = {};
        this._saveState();
        localStorage.removeItem(this.COMPLETE_KEY);
        localStorage.removeItem(this.SKIP_KEY);
        this.terminal.print('╔══════════════════════════════════════╗', 'success');
        this.terminal.print('║   🎮 newOS4 Tutorial Started!        ║', 'success');
        this.terminal.print('╚══════════════════════════════════════╝', 'success');
        this.terminal.print('Follow the quests below. Type the correct command to advance.', 'info');
        this._showQuestNext(this._getQuests()[0]);
    }

    skipTutorial() {
        localStorage.setItem(this.SKIP_KEY, '1');
        this._started = false;
        this._completed = new Set();
        this._activeIndex = 0;
        this._tries = {};
        localStorage.removeItem(this.STORAGE_KEY);
        this.terminal.print('Tutorial skipped. Type `tutorial start` to begin anytime, or `help` to see all commands.', 'info');
    }

    /** Show status of tutorial progress */
    showStatus() {
        const quests = this._getQuests();
        const total = quests.length;
        const done = this._completed.size;

        if (!this._started && !this.isComplete()) {
            this.terminal.print('📋 Tutorial has not been started. Type `tutorial start` to begin!', 'info');
            return;
        }
        if (this.isComplete()) {
            this.terminal.print('🎉 Tutorial complete! All ' + total + ' quests finished.', 'success');
            return;
        }

        this.terminal.print('📋 Tutorial Progress: ' + done + '/' + total + ' quests', 'info');
        quests.forEach((q, i) => {
            const status = this._completed.has(q.id) ? '✅' : (i === this._activeIndex ? '👉' : '⬜');
            this.terminal.print('  ' + status + ' Quest ' + q.id + ': ' + q.title);
        });
        if (this._activeIndex < total) {
            this.terminal.print('');
            this._showQuestNext(quests[this._activeIndex]);
        }
    }

    // ── Internal ──

    _handleTutorial(args) {
        if (!args || args.length === 0) {
            // No args — show status or start if first time
            if (!this._started && !this.isComplete()) {
                this.terminal.print('╔══════════════════════════════════════╗', 'info');
                this.terminal.print('║   🎮 newOS4 Interactive Tutorial     ║', 'info');
                this.terminal.print('╚══════════════════════════════════════╝', 'info');
                this.terminal.print('Learn newOS4 by completing 6 short quests.', 'info');
                this.terminal.print('');
                this.terminal.print('Commands:', 'info');
                this.terminal.print('  tutorial start   — Begin or restart the tutorial');
                this.terminal.print('  tutorial status  — Show your progress');
                this.terminal.print('  tutorial skip    — Dismiss the tutorial');
                return;
            }
            this.showStatus();
            return;
        }

        const sub = args[0].toLowerCase();
        if (sub === 'start') this.startTutorial();
        else if (sub === 'skip') this.skipTutorial();
        else if (sub === 'status') this.showStatus();
        else this.terminal.print('Usage: tutorial [start|skip|status]', 'warning');
    }

    _showQuestNext(quest) {
        this.terminal.print('── Quest ' + quest.id + '/' + this._getQuests().length + ': ' + quest.title + ' ──', 'info');
        this.terminal.print('  ' + quest.desc, 'text-muted');
        this.terminal.print('  💡 ' + quest.hint, 'warning');
    }

    _showCompletion() {
        // Guard: only fire once
        if (this._completionFired) return;
        this._completionFired = true;
        
        this.terminal.print('');
        this.terminal.print('🎉🎉🎉 CONGRATULATIONS! 🎉🎉🎉', 'success');
        this.terminal.print('═'.repeat(40), 'success');
        this.terminal.print('  All 6 quests complete!', 'success');
        this.terminal.print('  You now know the basics of newOS4.', 'success');
        this.terminal.print('═'.repeat(40), 'success');
        this.terminal.print('');
        this.terminal.print('What next?', 'info');
        this.terminal.print('  • Explore commands:  help', 'info');
        this.terminal.print('  • Full docs:         help.html', 'info');
        this.terminal.print('  • AI assistant:      ai \"your question\"', 'info');
        this.terminal.print('  • Schedule tasks:    cron-every 60 echo hello', 'info');
        this.terminal.print('  • Install packages:  wpm list', 'info');
        this.terminal.print('  • Manage files:      edit, find, grep, files', 'info');

        localStorage.setItem(this.COMPLETE_KEY, Date.now().toString());
        localStorage.removeItem(this.STORAGE_KEY);

        // Fire confetti
        this._fireConfetti();
    }

    _fireConfetti() {
        const emojis = ['🎉', '✨', '⭐', '🌟', '💫'];
        const container = document.body;
        if (!container) return;
        // Remove any previous confetti first
        document.querySelectorAll('.confetti-piece').forEach(el => el.remove());
        for (let i = 0; i < 15; i++) {
            const el = document.createElement('div');
            el.className = 'confetti-piece';
            el.textContent = emojis[i % emojis.length];
            el.style.left = (Math.random() * 100) + 'vw';
            el.style.animationDuration = (2 + Math.random() * 2) + 's';
            el.style.animationDelay = (Math.random() * 1.5) + 's';
            el.style.fontSize = (16 + Math.random() * 20) + 'px';
            container.appendChild(el);
            setTimeout(() => el.remove(), 5000);
        }
    }
}