// node modules/test/test-doctor-thresholds.js
// Proves `doctor` measures real storage cost and can actually fire:
//   · network comes from a live HEAD probe, never from the legacy onLine boolean;
//   · localStorage is charged as UTF-16 (Σ (key+value) × 2), against its own ~5 MB cap;
//   · VFS is summed as UTF-8 bytes of file content (Blob), the same unit vfs-size uses;
//   · navigator.storage.estimate() is CONTEXT ONLY — a 2 GB origin quota must NOT suppress a
//     4.5 MB localStorage finding. That is the exact defect in the proposed patch, whose
//     `lsBytes > quota * 0.8` comparison could never be true on a real browser.
// Run through the real class loaded from modules/core/module-system.js.
const fsMod = require('fs'), path = require('path');
const ROOT = path.join(__dirname, '..', 'core');
// N4_SRC lets the same assertions run against another build of the file (mutation check).
const SRC_PATH = process.env.N4_SRC || path.join(ROOT, 'module-system.js');

global.window = global;

const src = fsMod.readFileSync(SRC_PATH, 'utf8');
const SystemModule = new Function(src + '\nreturn SystemModule;')();

// ── a localStorage that charges what a browser charges ──────────────────────
// Values are held as given; the module must do the ×2 itself, so this fake reports
// .length (UTF-16 code units) exactly like the real Storage object does.
function makeLS(pairs) {
    const map = new Map(Object.entries(pairs || {}));
    return {
        get length() { return map.size; },
        key(i) { return Array.from(map.keys())[i] ?? null; },
        getItem(k) { return map.has(k) ? map.get(k) : null; },
        setItem(k, v) { map.set(k, String(v)); },
        removeItem(k) { map.delete(k); },
        clear() { map.clear(); },
        _map: map,
    };
}

// ── terminal stub ──────────────────────────────────────────────────────────
function mkTerminal(opts) {
    const out = [];
    const files = (opts && opts.files) || {};
    const dirs = (opts && opts.dirs) || { '/': [] };
    return {
        out,
        text: () => out.map(l => l.msg).join('\n'),
        fs: {
            root: (opts && opts.root) || { type: 'dir', content: {} },
            ls: () => (dirs['/'] || []),
            readDir: (p) => dirs[p] || null,
            readFile: (p) => (p in files ? files[p] : null),
        },
        ollamaManager: { connected: (opts && opts.ollama !== undefined) ? opts.ollama : true },
        moduleManager: { modules: { SystemModule: {}, VirtualFSModule: {} } },
        print: (msg, cls) => out.push({ msg: String(msg), cls: cls || '' }),
    };
}

function mkModule(opts) {
    const t = mkTerminal(opts);
    const m = new SystemModule();
    m.terminal = t;
    m.registerCommands();
    return { m, t };
}

let fails = 0, passes = 0;
function ok(name, cond, detail) {
    if (cond) { passes++; return; }
    fails++;
    console.log('FAIL ' + name + (detail ? ' — ' + detail : ''));
}

// ── helpers to build payloads of an exact byte size ────────────────────────
const kb = 1024;
function asciiFile(mb) { return 'a'.repeat(Math.round(mb * 1024 * 1024)); }

// A VFS file node tree holding one big ASCII file.
function rootWithFile(content) {
    return { type: 'dir', content: { tmp: { type: 'dir', content: { 'big.txt': { type: 'file', content } } } } };
}

// Drive `doctor` with a given fake browser surface.
async function doctor(opts) {
    const { m, t } = mkModule(opts);
    const o = opts || {};
    const savedNavigator = global.navigator;
    const savedFetch = global.fetch;
    const savedLS = global.localStorage;
    global.localStorage = o.ls || makeLS({});
    if ('fetch' in o) {
        if (o.fetch === undefined) delete global.fetch;
        else global.fetch = o.fetch;
    }
    if ('storage' in o) {
        const nav = Object.assign({}, savedNavigator);
        if (o.storage === undefined) delete nav.storage;
        else nav.storage = o.storage;
        Object.defineProperty(global, 'navigator', { value: nav, configurable: true, writable: true });
    }
    try {
        const r = m.commands['doctor']();
        if (r && typeof r.then === 'function') await r;
    } finally {
        global.fetch = savedFetch;
        global.localStorage = savedLS;
        Object.defineProperty(global, 'navigator', { value: savedNavigator, configurable: true, writable: true });
    }
    return t;
}

// Extract the issue lines the report printed (top 3) plus the full issue count line.
function issueLines(t) {
    return t.out.map(l => l.msg).filter(s => /^\s{4}\S+ \[(HIGH|MEDIUM|LOW)\]/.test(s));
}
function report(t) { return t.text(); }

function okFetch(status) {
    return () => Promise.resolve({ ok: status >= 200 && status < 300, status });
}

// ══════════════════════════════════════════════════════════════════════════
// A. Network — live probe, not the legacy boolean
// ══════════════════════════════════════════════════════════════════════════
(async () => {
    // A1: a healthy fetch must produce NO Network issue at all.
    {
        const t = await doctor({ fetch: okFetch(200), files: {} });
        ok('A1 fetch ok → no Network issue', !/Network: (unreachable|HTTP probe)/.test(report(t)), report(t));
        ok('A1b report says reachable', /Network:\s+reachable/.test(report(t)), report(t));
    }

    // A2: a rejected fetch must be a HIGH unreachable finding.
    {
        const t = await doctor({ fetch: () => Promise.reject(new Error('net::ERR_NAME_NOT_RESOLVED')) });
        const txt = report(t);
        ok('A2 fetch reject → high Network: unreachable',
            /\[HIGH\] Network: unreachable/.test(txt), txt);
    }

    // A3: a 503 must be named, not flattened to "offline".
    {
        const t = await doctor({ fetch: okFetch(503) });
        const txt = report(t);
        ok('A3 fetch 503 → Network issue naming http-503',
            /Network:.*http-503/.test(txt), txt);
        ok('A3b 503 is not reported as unreachable',
            !/Network: unreachable/.test(txt), txt);
    }

    // A4: legacy boolean must not exist in the source at all.
    {
        const hits = src.split('\n').filter(l => /navigator\s*\.\s*onLine/.test(l)).length;
        ok('A4 no navigator.onLine reference in module-system.js', hits === 0, hits + ' hit(s)');
    }

    // ══════════════════════════════════════════════════════════════════════
    // B. localStorage — UTF-16 cost against its own ~5 MB cap
    // ══════════════════════════════════════════════════════════════════════
    // 4.5 MB of UTF-16 = 2.25 M code units of value + key.
    {
        const t = await doctor({
            fetch: okFetch(200),
            ls: makeLS({ webx11_big: 'a'.repeat(Math.round(4.5 * 1024 * 1024 / 2)) }),
        });
        const txt = report(t);
        ok('B1 localStorage 4.5 MB → HIGH localStorage issue',
            /\[HIGH\] localStorage: 4\.5 MB/.test(txt), txt);
        ok('B1b message names the ~5 MB per-origin cap',
            /~5 MB per-origin cap/.test(txt), txt);
    }
    {
        // 3.2 MB of UTF-16 = 1.6 M code units.
        const t = await doctor({
            fetch: okFetch(200),
            ls: makeLS({ webx11_mid: 'b'.repeat(Math.round(3.2 * 1024 * 1024 / 2)) }),
        });
        const txt = report(t);
        ok('B2 localStorage 3.2 MB → MEDIUM', /\[MEDIUM\] localStorage: 3\.2 MB/.test(txt), txt);
        ok('B2b no HIGH localStorage at 3.2 MB', !/\[HIGH\] localStorage/.test(txt), txt);
    }
    {
        const t = await doctor({
            fetch: okFetch(200),
            ls: makeLS({ webx11_small: 'c'.repeat(Math.round(1 * 1024 * 1024 / 2)) }),
        });
        ok('B3 localStorage 1 MB → no localStorage issue',
            !/localStorage:/.test(report(t)), report(t));
    }

    // ══════════════════════════════════════════════════════════════════════
    // C. VFS — UTF-8 bytes of content, share of the localStorage budget
    // ══════════════════════════════════════════════════════════════════════
    {
        // 3.5 MB of ASCII VFS + 4 MB localStorage budget → 87% share → HIGH.
        const t = await doctor({
            fetch: okFetch(200),
            root: rootWithFile(asciiFile(3.5)),
            ls: makeLS({ webx11_vfs: 'd'.repeat(Math.round(4 * 1024 * 1024 / 2)) }),
        });
        const txt = report(t);
        ok('C1 VFS 3.5 MB of 4 MB budget → HIGH VFS issue',
            /\[HIGH\] VFS: 3\.5 MB/.test(txt), txt);
        ok('C1b message states the measured share', /87% of the 4\.0 MB localStorage budget/.test(txt), txt);
        ok('C1c VFS does not claim a JSON limit', !/512KB|256KB/.test(txt), txt);
    }
    {
        // 1 MB VFS → under both thresholds, nothing.
        const t = await doctor({
            fetch: okFetch(200),
            root: rootWithFile(asciiFile(1)),
            ls: makeLS({ webx11_vfs: 'e'.repeat(Math.round(4 * 1024 * 1024 / 2)) }),
        });
        ok('C2 VFS 1 MB → no VFS issue', !/VFS: /.test(report(t)), report(t));
    }
    {
        // 2.5 MB VFS → MEDIUM (large alone, but not a big share of an 8 MB budget).
        const t = await doctor({
            fetch: okFetch(200),
            root: rootWithFile(asciiFile(2.5)),
            ls: makeLS({ webx11_vfs: 'f'.repeat(Math.round(8 * 1024 * 1024 / 2)) }),
        });
        const txt = report(t);
        ok('C3 VFS 2.5 MB → MEDIUM', /\[MEDIUM\] VFS: 2\.5 MB/.test(txt), txt);
    }
    {
        // UTF-8, not chars: 1 MiB of 'é' is 2.00 MB of UTF-8 (chars would read 1.00 MB).
        const t = await doctor({
            fetch: okFetch(200),
            root: rootWithFile('é'.repeat(1024 * 1024)),
            ls: makeLS({ webx11_vfs: 'g'.repeat(Math.round(8 * 1024 * 1024 / 2)) }),
        });
        ok('C4 multibyte counted as UTF-8 bytes (1M é = 2.00 MB)',
            /Measured: VFS 2\.00 MB UTF-8/.test(report(t)), report(t));
    }

    // ══════════════════════════════════════════════════════════════════════
    // D. The patch's bug: origin quota must not suppress a real finding
    // ══════════════════════════════════════════════════════════════════════
    {
        const est = () => Promise.resolve({ usage: 40 * 1024 * 1024, quota: 2 * 1024 * 1024 * 1024 });
        const t = await doctor({
            fetch: okFetch(200),
            storage: { estimate: est },
            ls: makeLS({ webx11_big: 'h'.repeat(Math.round(4.5 * 1024 * 1024 / 2)) }),
        });
        const txt = report(t);
        ok('D1 2 GB origin quota does NOT suppress a 4.5 MB localStorage finding',
            /\[HIGH\] localStorage: 4\.5 MB/.test(txt), txt);
        ok('D2 quota is printed as context only',
            /Origin usage 40\.0 MB of ~2048 MB quota/.test(txt), txt);
        ok('D3 context line states localStorage has its own cap',
            /localStorage has its own ~5 MB cap/.test(txt), txt);
        ok('D4 quota does not turn a big VFS healthy either', !/All systems healthy/.test(txt), txt);
    }
    {
        // And a big quota must not invent an issue where none exists.
        const t = await doctor({
            fetch: okFetch(200),
            storage: { estimate: () => Promise.resolve({ usage: 10 * 1024 * 1024, quota: 2 * 1024 * 1024 * 1024 }) },
            ls: makeLS({ webx11_a: 'tiny' }),
        });
        ok('D5 healthy storage + huge quota → all healthy',
            /All systems healthy/.test(report(t)), report(t));
    }

    // ══════════════════════════════════════════════════════════════════════
    // E. Degraded browsers — every probe is individually guarded
    // ══════════════════════════════════════════════════════════════════════
    {
        const t = await doctor({ fetch: undefined, files: {} });
        const txt = report(t);
        ok('E1 fetch undefined → completes and prints a report',
            /Doctor Report/.test(txt) && /Measured: VFS/.test(txt), txt);
        ok('E1b no Network issue invented without a probe', !/Network: unreachable/.test(txt), txt);
    }
    {
        // Blob removed: the UTF-8 fallback must still measure 2 bytes per 'é'.
        const savedBlob = global.Blob;
        delete global.Blob;
        try {
            const t = await doctor({
                fetch: okFetch(200),
                root: rootWithFile('é'.repeat(1024 * 1024)),
                ls: makeLS({ webx11_vfs: 'i'.repeat(Math.round(8 * 1024 * 1024 / 2)) }),
            });
            ok('E2 Blob undefined → completes and still counts UTF-8 (2.00 MB)',
                /Doctor Report/.test(report(t)) && /Measured: VFS 2\.00 MB UTF-8/.test(report(t)), report(t));
        } finally {
            global.Blob = savedBlob;
        }
    }
    {
        const t = await doctor({ fetch: okFetch(200), storage: undefined, files: {} });
        const txt = report(t);
        ok('E3 storage.estimate undefined → completes, no quota line',
            /Doctor Report/.test(txt) && !/Origin usage/.test(txt), txt);
    }
    {
        // estimate() that throws must not kill the report.
        const t = await doctor({
            fetch: okFetch(200),
            storage: { estimate: () => Promise.reject(new Error('SecurityError')) },
        });
        ok('E4 estimate() rejecting → completes', /Doctor Report/.test(report(t)), report(t));
    }

    // ══════════════════════════════════════════════════════════════════════
    // F. status must not claim Online/Offline
    // ══════════════════════════════════════════════════════════════════════
    {
        const { m, t } = mkModule({ fetch: okFetch(200) });
        m.commands['status']();
        const txt = report(t);
        const netLine = t.out.map(l => l.msg).find(s => /^Network:/.test(s)) || '';
        ok('F1 status prints a Network line', netLine.length > 0, txt);
        ok('F2 status line says neither Online nor Offline',
            !/\b(Online|Offline)\b/.test(netLine), netLine);
        ok('F3 status points at doctor', /doctor/.test(netLine), netLine);
        ok('F4 status still reports files/modules/ollama',
            /^Files:/m.test(txt) && /^Modules:/m.test(txt) && /^Ollama:/m.test(txt), txt);
    }

    // ══════════════════════════════════════════════════════════════════════
    // G. Output shape kept: top 3 issues + Recommended actions
    // ══════════════════════════════════════════════════════════════════════
    {
        const t = await doctor({
            fetch: () => Promise.reject(new Error('down')),
            ollama: false,
            root: rootWithFile(asciiFile(3.5)),
            ls: makeLS({ webx11_big: 'j'.repeat(Math.round(4.5 * 1024 * 1024 / 2)) }),
            files: { '/logs/current.log': Array.from({ length: 900 }, () => 'x').join('\n') },
        });
        const txt = report(t);
        ok('G1 at most 3 issue lines printed', issueLines(t).length <= 3, issueLines(t).length + ' lines');
        ok('G2 remainder is summarised', /\.\.\. and \d+ more/.test(txt), txt);
        ok('G3 Recommended actions section present', /Recommended actions:/.test(txt), txt);
    }

    // ── summary ───────────────────────────────────────────────────────────
    console.log('\n' + passes + '/' + (passes + fails) + ' assertions passed');
    if (fails > 0) { console.log(fails + ' FAILED'); process.exit(1); }
})();