#!/usr/bin/env node
/**
 * ObsiGate — Forge autocomplete tests (BUG-055).
 *
 * The Forge editor (`frontend/editor-poc.html`) shares its pure completion
 * helpers with CodeMirror through `frontend/js/autocomplete.js`. This suite
 * pins the behaviour that fixes the « Tab adds a stray space » bug:
 *
 *   - getWordFragment / findWordCompletions — document word completion
 *   - normalizeGhost                      — AI inline prediction cleanup
 *   - chooseTabAction                     — single action per Tab press
 *
 * Usage: node tests/frontend/forge-completion.test.mjs
 */

import { strict as assert } from "node:assert";
import { fileURLToPath, pathToFileURL } from "node:url";
import path from "node:path";

const __filename = fileURLToPath(import.meta.url);
const __dirname = path.dirname(__filename);
const REPO_ROOT = path.resolve(__dirname, "..", "..");

const mod = await import(
  pathToFileURL(path.join(REPO_ROOT, "frontend", "js", "autocomplete.js")).href
);
const {
  isWordChar,
  getWordFragment,
  findWordCompletions,
  normalizeGhost,
  chooseTabAction,
} = mod;

let testCount = 0;
let failCount = 0;

function test(name, fn) {
  testCount++;
  try {
    fn();
    console.log(`  ✓ ${name}`);
  } catch (err) {
    failCount++;
    console.error(`  ✗ ${name}\n    ${err.message}`);
    process.exitCode = 1;
  }
}

// ── isWordChar ─────────────────────────────────────────────────────────────
test("isWordChar accepts letters, digits, _ - . /", () => {
  for (const ch of ["a", "Z", "0", "_", "-", ".", "/"]) {
    assert.equal(isWordChar(ch), true, `expected ${JSON.stringify(ch)} to be a word char`);
  }
});

test("isWordChar rejects spaces and punctuation", () => {
  for (const ch of [" ", "\n", "!", "@", "#", "(", "\t"]) {
    assert.equal(isWordChar(ch), false, `expected ${JSON.stringify(ch)} not to be a word char`);
  }
  assert.equal(isWordChar(""), false);
  assert.equal(isWordChar(undefined), false);
});

// ── getWordFragment ────────────────────────────────────────────────────────
test("getWordFragment returns the fragment before the cursor", () => {
  const text = "hello wor";
  assert.deepEqual(getWordFragment(text, text.length), { start: 6, fragment: "wor" });
});

test("getWordFragment stops at non-word characters", () => {
  const text = "a (tabl";
  assert.deepEqual(getWordFragment(text, text.length), { start: 3, fragment: "tabl" });
});

test("getWordFragment returns an empty fragment at a word boundary", () => {
  const text = "hello ";
  assert.deepEqual(getWordFragment(text, text.length), { start: 6, fragment: "" });
});

test("getWordFragment handles a mid-document cursor", () => {
  const text = "one two three";
  // cursor right after "tw"
  assert.deepEqual(getWordFragment(text, 6), { start: 4, fragment: "tw" });
});

// ── findWordCompletions ────────────────────────────────────────────────────
test("findWordCompletions returns prefix matches from the document", () => {
  const text = "table tableau tab\n";
  const cursor = text.length;
  assert.deepEqual(findWordCompletions(text, cursor, "tab", 8), ["table", "tableau"]);
});

test("findWordCompletions ignores the occurrence being typed", () => {
  const text = "table and tab";
  const cursor = text.length; // typing the trailing "tab"
  assert.deepEqual(findWordCompletions(text, cursor, "tab", 8), ["table"]);
});

test("findWordCompletions is case-insensitive and unique", () => {
  const text = "Table TABLE table\n";
  const cursor = text.length;
  assert.deepEqual(findWordCompletions(text, cursor, "tab", 8), ["Table"]);
});

test("findWordCompletions completes file-like tokens", () => {
  const text = "docs/guide.md docs/guide\n";
  const cursor = text.length;
  assert.deepEqual(findWordCompletions(text, cursor, "docs/", 8), ["docs/guide.md", "docs/guide"]);
});

test("findWordCompletions honours the limit", () => {
  const text = "abc abd abe abf abg\n";
  const cursor = text.length;
  assert.equal(findWordCompletions(text, cursor, "ab", 3).length, 3);
});

test("findWordCompletions needs at least two characters", () => {
  const text = "apple apricot\n";
  assert.deepEqual(findWordCompletions(text, text.length, "a", 8), []);
  assert.deepEqual(findWordCompletions(text, text.length, "", 8), []);
});

// ── normalizeGhost ─────────────────────────────────────────────────────────
test("normalizeGhost strips an echoed prefix (mid-word)", () => {
  assert.equal(normalizeGhost("familial", "famil", true), "ial");
});

test("normalizeGhost keeps only the first token for a word completion", () => {
  // A word completion must never introduce a space.
  assert.equal(normalizeGhost("familial and more", "famil", true), "ial");
});

test("normalizeGhost tolerates a leading space from the model", () => {
  assert.equal(normalizeGhost("  monde", "bonjour", false), "monde");
});

test("normalizeGhost strips a repeated full context", () => {
  assert.equal(normalizeGhost("Bonjour le monde", "Bonjour", false), " le monde".trim());
});

test("normalizeGhost returns an empty string for empty input", () => {
  assert.equal(normalizeGhost("", "abc", true), "");
  assert.equal(normalizeGhost(null, "abc", true), "");
  assert.equal(normalizeGhost("   ", "abc", false), "");
});

test("normalizeGhost keeps a phrase continuation intact", () => {
  assert.equal(normalizeGhost("la suite de la phrase.", "Voici", false), "la suite de la phrase.");
});

// ── chooseTabAction ────────────────────────────────────────────────────────
test("chooseTabAction prioritises the open list", () => {
  assert.equal(chooseTabAction({ dropdownOpen: true, ghost: true }), "dropdown");
});

test("chooseTabAction accepts a ghost prediction before word completion", () => {
  assert.equal(chooseTabAction({ ghost: true, candidates: ["table"] }), "ghost");
});

test("chooseTabAction inserts a single word match", () => {
  assert.equal(chooseTabAction({ candidates: ["table"] }), "word");
});

test("chooseTabAction opens the list for several matches", () => {
  assert.equal(chooseTabAction({ candidates: ["table", "tableau"] }), "word-list");
});

test("chooseTabAction indents when nothing matches", () => {
  assert.equal(chooseTabAction({ candidates: [] }), "indent");
  assert.equal(chooseTabAction({}), "indent");
});

test("chooseTabAction dedents on Shift+Tab", () => {
  assert.equal(chooseTabAction({ shiftKey: true }), "dedent");
  assert.equal(chooseTabAction({ shiftKey: true, candidates: ["table"] }), "dedent");
});

test("chooseTabAction indents when a selection exists", () => {
  assert.equal(chooseTabAction({ hasSelection: true, candidates: ["table"] }), "indent");
});

// ── Static wiring of frontend/editor-poc.html ──────────────────────────────
import { readFileSync } from "node:fs";
const FORGE_HTML = readFileSync(
  path.join(REPO_ROOT, "frontend", "editor-poc.html"),
  "utf-8",
);

test("Forge uses the shared completion helpers", () => {
  for (const call of ["ac.getWordFragment(", "ac.findWordCompletions(", "ac.chooseTabAction("]) {
    assert.ok(FORGE_HTML.includes(call), `editor-poc.html must call ${call}`);
  }
});

test("Forge has a single indentation call site (no double Tab handling)", () => {
  const indentCalls = FORGE_HTML.match(/indentLine\(\);/g) || [];
  assert.equal(indentCalls.length, 1, "indentLine() must only be called from the unified Tab handler");
});

test("Forge ghost text no longer mirrors the whole document", () => {
  assert.ok(!FORGE_HTML.includes("ghostOverlay.innerHTML"), "the mirror overlay must be gone");
});

test("Forge ignores its own autosave reload while the buffer is dirty (BUG-055)", () => {
  assert.ok(
    FORGE_HTML.includes("if (!e.data.force && isDirty) return;"),
    "parent-reload must not clobber unsaved local edits",
  );
});

test("Forge cancels a pending ghost request when the prediction is accepted", () => {
  const fn = FORGE_HTML.match(/function acceptGhost\(\) \{([\s\S]*?)\n  \}/);
  assert.ok(fn, "acceptGhost not found");
  assert.match(fn[1], /clearTimeout\(_ghostTimer\)/);
});

test("Forge autosave keeps the buffer dirty if edits arrive during the request", () => {
  const fn = FORGE_HTML.match(/function autoSave\(\) \{([\s\S]*?)\n  \}/);
  assert.ok(fn, "autoSave not found");
  assert.match(fn[1], /if \(val\(\) !== content\) \{ scheduleAutoSave\(\); return; \}/);
});

test("Forge leaves fullscreen before opening the shared assistant", () => {
  const fn = FORGE_HTML.match(/function openAssistant\(\) \{([\s\S]*?)\n  \}/);
  assert.ok(fn, "openAssistant not found");
  assert.match(fn[1], /document\.fullscreenElement/);
  assert.match(fn[1], /document\.exitFullscreen\(\)/);
  assert.match(fn[1], /postMessage\(\{ type: 'forge-open-ai' \}, '\*'\)/);
});

// ── Summary ────────────────────────────────────────────────────────────────
console.log(`\n${testCount} passed, ${failCount} failed`);
process.exit(failCount > 0 ? 1 : 0);