// modules/test/test-memory-graph-recovery.js — run: node
// MAINT-003: a corrupt memory-graph store must not look like a fresh install. The graph still
// starts from what remains, but the unreadable file is kept aside and the user is told.
const fsMod = require('fs'), path = require('path');
const ROOT = path.join(__dirname, '..', 'core');
const store = {};
global.localStorage = { getItem: k => (k in store ? store[k] : null), setItem: (k, v) => { store[k] = String(v); }, removeItem: k => { delete store[k]; } };
global.indexedDB = { open() { throw new Error('no idb'); }, deleteDatabase() { throw new Error('no idb'); } };
global.window = global;

const load = (f, c) => new Function(fsMod.readFileSync(path.join(ROOT, f), 'utf8') + '\nreturn ' + c + ';')();
const VFS = load('virtual-fs.js', 'VirtualFileSystem');
const MG = load('module-memory-graph.js', 'MemoryGraphModule');

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

function mk() {
    const out = [];
    const vfs = new VFS();
    vfs.saveToStorage = () => true;
    const term = { print: (m, t) => out.push({ text: String(m), type: t || '' }), log: () => {}, fs: vfs };
    const mg = new MG();
    mg.init(term);
    return { mg, vfs, out };
}
const text = out => out.map(o => o.text).join(' | ');

// A. a healthy store survives a reload
{
    const a = mk();
    for (let i = 0; i < 4; i++) a.mg.addNode('concept', 'keep-' + i, 'keep ' + i);
    a.mg._saveNow();
    const seeded = Object.keys(a.mg._nodes).length;

    const out = [];
    const mg2 = new MG();
    mg2.init({ print: (m, t) => out.push({ text: String(m), type: t || '' }), log: () => {}, fs: a.vfs });
    ok('A1 nodes survive a reload', Object.keys(mg2._nodes).length === seeded, 'seeded ' + seeded + ' reloaded ' + Object.keys(mg2._nodes).length);
    ok('A2 no quarantine warning on a healthy store', !/unreadable/.test(text(out)), text(out));
}

// B. a corrupt store is quarantined and reported, not silently discarded
{
    const a = mk();
    for (let i = 0; i < 4; i++) a.mg.addNode('concept', 'lose-' + i, 'lose ' + i);
    a.mg._saveNow();
    const original = a.vfs.readFile('/.memory_graph/nodes.json');
    a.vfs.writeFile('/.memory_graph/nodes.json', '{"nodes":[');   // truncated write
    a.vfs.writeFile('/.memory_graph/export.json', 'not json at all');

    const out = [];
    const mg2 = new MG();
    mg2.init({ print: (m, t) => out.push({ text: String(m), type: t || '' }), log: () => {}, fs: a.vfs });

    ok('B1 the user is warned', /unreadable/.test(text(out)), text(out).slice(0, 200));
    ok('B2 the corrupt file is kept aside', a.vfs.readFile('/.memory_graph/nodes.json.corrupt') === '{"nodes":[',
        String(a.vfs.readFile('/.memory_graph/nodes.json.corrupt')));
    ok('B3 the quarantine copy held the broken text, not the old good one', original !== a.vfs.readFile('/.memory_graph/nodes.json.corrupt'));
    ok('B4 the graph still starts', Object.keys(mg2._nodes).length >= 1, String(Object.keys(mg2._nodes).length));
}

// C. the export path is quarantined too, and the nodes.json fallback still loads
{
    const a = mk();
    a.mg.addNode('concept', 'fallback', 'fallback node');
    a.mg._saveNow();
    // the loader expects {nodes: [...], edges: [...]}
    a.vfs.fsWriteJSON('/.memory_graph/export.json', { nodes: Object.values(a.mg._nodes), edges: [] });
    a.vfs.writeFile('/.memory_graph/nodes.json', 'broken');          // corrupt fallback
    const before = Object.keys(a.mg._nodes).length;

    const out = [];
    const mg2 = new MG();
    mg2.init({ print: (m, t) => out.push({ text: String(m), type: t || '' }), log: () => {}, fs: a.vfs });
    ok('C1 corrupt nodes.json is quarantined', !!a.vfs.readFile('/.memory_graph/nodes.json.corrupt'));
    ok('C2 the valid export still loads the graph', Object.keys(mg2._nodes).length >= before,
        'before ' + before + ' after ' + Object.keys(mg2._nodes).length);
}

if (fails === 0) {
    console.log('test-memory-graph-recovery: ' + passes + ' passed, 0 failed');
} else {
    console.log('test-memory-graph-recovery: ' + passes + ' passed, ' + fails + ' FAILED');
    process.exit(1);
}