class BusyBoxModule {
    constructor() {
        this.commands = {};
        this.terminal = null;
    }

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

    getHelpInfo() {
        return {
            'which': 'which <name> — Locate a command in the module registry',
            'env': 'env — List environment variables (webx11_ keys + user profile)',
            'date': 'date — Show current date/time (ISO, local, UTC, timestamp)',
            'cal': 'cal [month] [year] — Display an ASCII calendar',
            'yes': 'yes [string] — Output repeated string (default "y", capped at 50)',
            'seq': 'seq <last> or seq <first> <last> — Generate sequence of numbers',
            'base64': 'base64 [-d] <string> — Base64 encode/decode',
            'printf': 'printf <format> [args...] — Formatted print (%s, %d, %f, \\n, \\t)',
            'cut': 'cut -f<N> [-d<delim>] <file> — Extract column from file',
            'uniq': 'uniq <file> — Filter adjacent duplicate lines from a file',
            'hostname': 'hostname — Show host/user-agent info',
            'whoami': 'whoami — Show current user name',
            'basename': 'basename <path> — Strip directory from path',
            'dirname': 'dirname <path> — Strip filename from path',
            'sleep': 'sleep <seconds> — Delay execution with countdown',
            'expand': 'expand <file> — Convert tabs to spaces (default 4) in file',
        };
    }

    registerCommands() {
        this.commands['which'] = (args) => this._cmdWhich(args);
        this.commands['env'] = () => this._cmdEnv();
        this.commands['date'] = (args) => this._cmdDate(args);
        this.commands['cal'] = (args) => this._cmdCal(args);
        this.commands['yes'] = (args) => this._cmdYes(args);
        this.commands['seq'] = (args) => this._cmdSeq(args);
        this.commands['base64'] = (args) => this._cmdBase64(args);
        this.commands['printf'] = (args) => this._cmdPrintf(args);
        this.commands['cut'] = (args) => this._cmdCut(args);
        this.commands['uniq'] = (args) => this._cmdUniq(args);
        this.commands['hostname'] = () => this._cmdHostname();
        this.commands['whoami'] = () => this._cmdWhoami();
        this.commands['basename'] = (args) => this._cmdBasename(args);
        this.commands['dirname'] = (args) => this._cmdDirname(args);
        this.commands['sleep'] = (args) => this._cmdSleep(args);
        this.commands['expand'] = (args) => this._cmdExpand(args);
    }

    // ── which ──

    _cmdWhich(args) {
        if (!args[0]) return this.terminal.print('Usage: which <name>', 'warning');
        const query = args[0].toLowerCase();
        const all = this.terminal.moduleManager.getAllCommands();
        const keys = Object.keys(all);

        if (all[query]) {
            let foundMod = null;
            for (const modName in this.terminal.moduleManager.modules) {
                const mod = this.terminal.moduleManager.modules[modName];
                if (mod.commands && mod.commands[query]) { foundMod = mod; break; }
            }
            const src = foundMod ? ` (from ${foundMod.constructor.name})` : '';
            return this.terminal.print(`${query}${src}`, 'info');
        }

        // Fuzzy match: check Levenshtein distance up to 2
        let best = null, bestDist = 3;
        for (const k of keys) {
            const d = this._levenshtein(query, k);
            if (d < bestDist) { best = k; bestDist = d; }
        }
        if (best) {
            this.terminal.print(`which: no '${query}' in registry`, 'error');
            this.terminal.print(`Did you mean '${best}'?`, 'info');
        } else {
            this.terminal.print(`which: no '${query}' in registry`, 'error');
        }
    }

    _levenshtein(a, b) {
        const m = a.length, n = b.length;
        const dp = Array.from({ length: m + 1 }, () => Array(n + 1).fill(0));
        for (let i = 0; i <= m; i++) dp[i][0] = i;
        for (let j = 0; j <= n; j++) dp[0][j] = j;
        for (let i = 1; i <= m; i++) {
            for (let j = 1; j <= n; j++) {
                dp[i][j] = a[i-1] === b[j-1] ? dp[i-1][j-1]
                    : 1 + Math.min(dp[i-1][j], dp[i][j-1], dp[i-1][j-1]);
            }
        }
        return dp[m][n];
    }

    // ── env ──

    _cmdEnv() {
        const lines = [];
        // webx11_ localStorage keys
        for (let i = 0; i < localStorage.length; i++) {
            const k = localStorage.key(i);
            if (k && k.startsWith('webx11_')) {
                let v = localStorage.getItem(k) || '';
                if (v.length > 80) v = v.substring(0, 77) + '...';
                lines.push(`${k}=${v}`);
            }
        }
        // Runtime info
        if (this.terminal.ollamaManager) {
            lines.push(`OLLAMA_MODEL=${this.terminal.ollamaManager.currentModel || 'none'}`);
            lines.push(`OLLAMA_CONNECTED=${this.terminal.ollamaManager.connected}`);
        }
        lines.push(`PWD=/${this.terminal.fs.currentPath.join('/')}`);
        lines.push(`SHELL=webx11-terminal`);
        lines.push(`USER=darkbot`);
        lines.push(`HOME=/`);
        lines.push(`TERM=xterm-256color`);
        const prof = this.terminal.moduleManager.modules['WebX11AIAssistantModule'];
        if (prof && prof._userProfile) {
            const facts = prof._userProfile.knownFacts;
            if (facts) {
                for (const [k, v] of Object.entries(facts)) {
                    lines.push(`USER_${k.toUpperCase()}=${v}`);
                }
            }
        }
        this.terminal.print(lines.join('\n'), 'info');
    }

    // ── date ──

    _cmdDate(args) {
        const n = new Date();
        if (args.length > 0) {
            const flag = args[0].toLowerCase();
            if (flag === '-u' || flag === '--utc' || flag === 'utc')
                return this.terminal.print(n.toUTCString(), 'info');
            if (flag === '-i' || flag === '--iso' || flag === 'iso')
                return this.terminal.print(n.toISOString(), 'info');
            if (flag === '-t' || flag === '--ts' || flag === 'timestamp')
                return this.terminal.print(String(n.getTime()), 'info');
            if (flag === '-r' || flag === '--rfc' || flag === 'rfc')
                return this.terminal.print(n.toUTCString(), 'info');
        }
        const local = n.toLocaleString('en-US', {
            weekday: 'long', year: 'numeric', month: 'long', day: 'numeric',
            hour: '2-digit', minute: '2-digit', second: '2-digit',
            timeZoneName: 'short'
        });
        this.terminal.print(local, 'info');
        this.terminal.print(`ISO:  ${n.toISOString()}`, 'info');
        this.terminal.print(`UTC:  ${n.toUTCString()}`, 'info');
        this.terminal.print(`Unix: ${Math.floor(n.getTime() / 1000)}`, 'info');
    }

    // ── cal ──

    _cmdCal(args) {
        const now = new Date();
        let year = now.getFullYear();
        let month = now.getMonth() + 1;

        if (args.length >= 2) {
            month = parseInt(args[0]);
            year = parseInt(args[1]);
        } else if (args.length === 1) {
            // If only one arg, could be year (4 digits) or month
            const v = parseInt(args[0]);
            if (args[0].length === 4 || v > 12) {
                year = v;
            } else {
                month = v;
            }
        }

        if (isNaN(month) || isNaN(year) || month < 1 || month > 12) {
            return this.terminal.print('cal: invalid month or year', 'error');
        }

        const monthNames = ['January','February','March','April','May','June',
            'July','August','September','October','November','December'];

        const first = new Date(year, month - 1, 1);
        const last = new Date(year, month, 0);
        const daysInMonth = last.getDate();
        const startDay = first.getDay(); // 0=Sun

        const header = `     ${monthNames[month-1]} ${year}`;
        const weekdays = 'Su Mo Tu We Th Fr Sa';

        let cal = header + '\n' + weekdays + '\n';

        let line = '  '.repeat(startDay);
        for (let d = 1; d <= daysInMonth; d++) {
            line += String(d).padStart(2) + ' ';
            if ((startDay + d) % 7 === 0 || d === daysInMonth) {
                cal += line.trimEnd() + '\n';
                line = '';
            }
        }

        this.terminal.print(cal, 'info');
    }

    // ── yes ──

    _cmdYes(args) {
        const text = args.length > 0 ? args.join(' ') : 'y';
        const count = 50;
        for (let i = 0; i < count; i++) {
            this.terminal.print(text);
        }
        this.terminal.print(`(repeated ${count} times, capped)`, 'text-muted');
    }

    // ── seq ──

    _cmdSeq(args) {
        if (args.length === 0) return this.terminal.print('Usage: seq <last> or seq <first> <last>', 'warning');
        let first = 1, last;
        if (args.length === 1) {
            last = parseInt(args[0]);
        } else {
            first = parseInt(args[0]);
            last = parseInt(args[1]);
        }
        if (isNaN(first) || isNaN(last)) return this.terminal.print('seq: non-integer argument', 'error');
        const max = 1000;
        if (last - first > max) return this.terminal.print(`seq: range too large (max ${max})`, 'error');
        const output = [];
        if (first <= last) {
            for (let i = first; i <= last; i++) output.push(String(i));
        } else {
            for (let i = first; i >= last; i--) output.push(String(i));
        }
        this.terminal.print(output.join('\n'), 'info');
    }

    // ── base64 ──

    _cmdBase64(args) {
        if (args.length === 0) return this.terminal.print('Usage: base64 [-d] <string>', 'warning');
        if (args[0] === '-d' || args[0] === '--decode') {
            if (args.length < 2) return this.terminal.print('Usage: base64 -d <encoded>', 'warning');
            const encoded = args.slice(1).join(' ');
            try {
                const decoded = atob(encoded);
                this.terminal.print(decoded, 'info');
            } catch (e) {
                this.terminal.print('base64: invalid input (not valid base64)', 'error');
            }
        } else {
            const input = args.join(' ');
            this.terminal.print(btoa(input), 'info');
        }
    }

    // ── printf ──

    _cmdPrintf(args) {
        if (args.length === 0) return this.terminal.print('Usage: printf <format> [args...]', 'warning');
        let fmt = args[0];
        const vals = args.slice(1);
        let vi = 0;
        // Replace format specifiers step by step
        const result = fmt
            .replace(/\\n/g, '\n')
            .replace(/\\t/g, '\t')
            .replace(/\\\\/g, '\\')
            .replace(/%s/g, () => vals[vi++] || '')
            .replace(/%d/g, () => {
                const v = parseInt(vals[vi++]);
                return isNaN(v) ? '0' : String(v);
            })
            .replace(/%f/g, () => {
                const v = parseFloat(vals[vi++]);
                return isNaN(v) ? '0.000000' : v.toFixed(6);
            })
            .replace(/%[^sdf%]/g, (m) => `(unsupported: ${m})`);
        this.terminal.print(result, 'info');
    }

    // ── cut ──

    _cmdCut(args) {
        if (args.length < 2) return this.terminal.print('Usage: cut -f<N> [-d<delim>] <file>', 'warning');
        let field = null, delim = '\t', file = '';
        for (const a of args) {
            if (a.startsWith('-f')) field = parseInt(a.substring(2));
            else if (a.startsWith('-d')) delim = a.substring(2);
            else file = a;
        }
        if (!field || isNaN(field)) return this.terminal.print('cut: -f flag required', 'error');
        if (!file) return this.terminal.print('cut: file argument required', 'error');

        const content = this.terminal.fs.readFile(file);
        if (content === null) return this.terminal.print(`cut: ${file}: No such file`, 'error');

        const lines = content.split('\n').filter(l => l);
        const output = [];
        for (const line of lines) {
            const parts = line.split(delim);
            const idx = field - 1;
            if (idx >= 0 && idx < parts.length) {
                output.push(parts[idx]);
            }
        }
        this.terminal.print(output.join('\n'), 'info');
    }

    // ── uniq ──

    _cmdUniq(args) {
        if (!args[0]) return this.terminal.print('Usage: uniq <file>', 'warning');
        const content = this.terminal.fs.readFile(args[0]);
        if (content === null) return this.terminal.print(`uniq: ${args[0]}: No such file`, 'error');
        const lines = content.split('\n');
        let last = null;
        const output = [];
        for (const line of lines) {
            if (line !== last) {
                output.push(line);
                last = line;
            }
        }
        this.terminal.print(output.join('\n'), 'info');
    }

    // ── hostname ──

    _cmdHostname() {
        const ua = navigator.userAgent;
        const space = 'newos4';
        const platform = navigator.platform || 'unknown';
        const version = 'WebX11 ' + (window.NEWOS4_VERSION || 'v4.0');
        this.terminal.print(`Hostname: ${space}`, 'info');
        this.terminal.print(`Platform: ${version} on ${platform}`, 'info');
        this.terminal.print(`User Agent: ${ua}`, 'info');
    }

    // ── whoami ──

    _cmdWhoami() {
        // Try to get from user profile
        let name = 'darkbot';
        try {
            const prof = this.terminal.moduleManager.modules['WebX11AIAssistantModule'];
            if (prof && prof._userProfile && prof._userProfile.knownFacts && prof._userProfile.knownFacts.name) {
                name = prof._userProfile.knownFacts.name;
            }
        } catch (e) {}
        this.terminal.print(name, 'info');
    }

    // ── basename ──

    _cmdBasename(args) {
        if (!args[0]) return this.terminal.print('Usage: basename <path>', 'warning');
        const parts = args[0].split('/').filter(p => p);
        const result = parts.pop() || '/';
        this.terminal.print(result, 'info');
    }

    // ── dirname ──

    _cmdDirname(args) {
        if (!args[0]) return this.terminal.print('Usage: dirname <path>', 'warning');
        const parts = args[0].split('/').filter(p => p);
        if (parts.length <= 1) {
            this.terminal.print('.', 'info');
            return;
        }
        parts.pop();
        const result = args[0].startsWith('/') ? '/' + parts.join('/') : parts.join('/');
        this.terminal.print(result || '.', 'info');
    }

    // ── sleep ──

    _cmdSleep(args) {
        if (!args[0]) return this.terminal.print('Usage: sleep <seconds>', 'warning');
        const secs = parseInt(args[0]);
        if (isNaN(secs) || secs < 1) return this.terminal.print('sleep: invalid duration', 'error');
        const max = 30;
        const actual = Math.min(secs, max);
        if (actual !== secs) this.terminal.print(`sleep: capped to ${max}s (from ${secs}s)`, 'warning');
        this.terminal.print(`Sleeping ${actual}s...`, 'info');
        let remaining = actual;
        const interval = setInterval(() => {
            remaining--;
            if (remaining > 0) {
                this.terminal.print(`${remaining}s...`, 'info');
            } else {
                clearInterval(interval);
                this.terminal.print('Done', 'success');
            }
        }, 1000);
    }

    // ── expand ──

    _cmdExpand(args) {
        if (!args[0]) return this.terminal.print('Usage: expand <file>', 'warning');
        const content = this.terminal.fs.readFile(args[0]);
        if (content === null) return this.terminal.print(`expand: ${args[0]}: No such file`, 'error');
        const expanded = content.replace(/\t/g, '    ');
        this.terminal.print(expanded, 'info');
    }
}
if (typeof window.webx11 !== 'undefined' && window.webx11) {
    webx11.moduleManager.registerModule(new BusyBoxModule(), 'https://webx11.duckdns.org/spaces/newos4/modules/ext/busybox.js');
}