import assert from "node:assert/strict";
import crypto from "node:crypto";
import fs from "node:fs";
import os from "node:os";
import path from "node:path";
import { spawnSync } from "node:child_process";
import { fileURLToPath } from "node:url";

const root = path.resolve(path.dirname(fileURLToPath(import.meta.url)), "../..");
const manifestPath = path.join(root, "tests/golden/M12-07B/manifest.json");
const reportPath = path.join(root, "tests/golden/M12-07B/desktop-fixtures.json");
const fixtureRoot = path.join(root, "tests/files/web/m12_obj_multi_v1");
const generator = path.join(root, "tools/web/generate-obj-multi-negative-fixtures.py");
const blender = process.env.BLENDER_BIN ?? path.join(root, "build_blender_5.2.0/bin/blender");
const sha256 = (bytes) => crypto.createHash("sha256").update(bytes).digest("hex");
const fileHash = (file) => sha256(fs.readFileSync(file));
const readJson = (file) => JSON.parse(fs.readFileSync(file, "utf8"));

function parseObj(file) {
  const positions = [];
  const texcoords = [];
  const normals = [];
  const faces = [];
  const groups = [];
  let object = null;
  let material = null;
  for (const raw of fs.readFileSync(file, "utf8").split(/\r?\n/)) {
    const line = raw.trim();
    if (!line || line.startsWith("#")) continue;
    const parts = line.split(/\s+/);
    if (parts[0] === "v") positions.push(parts.slice(1));
    else if (parts[0] === "vt") texcoords.push(parts.slice(1));
    else if (parts[0] === "vn") normals.push(parts.slice(1));
    else if (parts[0] === "g") {
      for (const group of parts.slice(1)) {
        groups.push(group);
        if (group.endsWith("_Mesh")) object = group;
      }
    }
    else if (parts[0] === "usemtl") material = parts.slice(1).join(" ");
    else if (parts[0] === "f") faces.push({ object, material, tokens: parts.slice(1) });
  }
  return { positions, texcoords, normals, groups, objects: [...new Set(faces.map((face) => face.object).filter(Boolean))], faces };
}

const manifest = readJson(manifestPath);
const report = readJson(reportPath);
assert.deepEqual(
  { schemaVersion: manifest.schemaVersion, task: manifest.task, parentTask: manifest.parentTask, nextTask: manifest.nextTask },
  { schemaVersion: 1, task: "M12-07B", parentTask: "M12-07A", nextTask: "M12-07C" },
);
assert.deepEqual(
  { schemaVersion: report.schemaVersion, task: report.task, operation: report.operation, nextTask: report.nextTask },
  { schemaVersion: 1, task: "M12-07B", operation: "DESKTOP_OBJ_MULTI_OBJECT_AND_NEGATIVE_FIXTURES", nextTask: "M12-07C" },
);
for (const artifact of Object.values(manifest.artifacts)) {
  if (artifact.path === manifestPath) continue;
  const absolute = path.join(root, artifact.path);
  assert.ok(fs.existsSync(absolute), `missing artifact ${artifact.path}`);
  assert.equal(fileHash(absolute), artifact.sha256, `hash mismatch ${artifact.path}`);
}
const inventory = readJson(path.join(root, "tests/golden/M12-05A/format-inventory.json"));
for (const key of ["blenderVersion", "versionTuple", "buildDate", "buildTime", "buildHash", "buildBranch", "buildPlatform", "buildType", "binarySha256"]) {
  assert.deepEqual(report.runtime[key], inventory.runtime[key], `runtime drift in ${key}`);
}
assert.equal(report.semantic.objects.length, 2);
assert.equal(report.semantic.positions.length, 6);
assert.equal(report.semantic.texcoords.length, 6);
assert.equal(report.semantic.normals.length, 2);
assert.equal(report.semantic.faces.length, 2);
assert.equal(report.semantic.materials.length, 2);
assert.deepEqual(report.textureOrigin, { mtlMapKd: ["m12_obj_texture.png", "m12_obj_texture.png"], relative: true, textureFile: "m12_obj_texture.png" });
assert.deepEqual(report.negativeIndex, { file: "negative-index.obj", expectedStatus: "ACCEPT_WITH_NEGATIVE_INDICES", faceCount: 2 });
assert.deepEqual(report.malformedFace, { file: "malformed-face.obj", expectedCode: "OBJ_FACE_ARITY_INVALID" });
const positive = parseObj(path.join(fixtureRoot, "multi-object.obj"));
assert.equal(positive.objects.length, 2);
assert.equal(positive.faces.length, 2);
assert.ok(positive.faces.every((face) => face.tokens.length === 3));
assert.ok(positive.faces.every((face) => face.tokens.every((token) => token.split("/").length === 3)));
const negative = parseObj(path.join(fixtureRoot, "negative-index.obj"));
assert.ok(negative.faces.every((face) => face.tokens.every((token) => token.split("/").every((index) => Number(index) < 0))));
assert.equal(negative.faces.length, 2);
const malformed = parseObj(path.join(fixtureRoot, "malformed-face.obj"));
assert.equal(malformed.faces[0].tokens.length, 2);
assert.equal(malformed.faces[0].tokens.length === 3 ? "ACCEPTED" : "OBJ_FACE_ARITY_INVALID", "OBJ_FACE_ARITY_INVALID");
const texture = fs.readFileSync(path.join(fixtureRoot, "m12_obj_texture.png"));
assert.deepEqual([...texture.subarray(0, 8)], [137, 80, 78, 71, 13, 10, 26, 10]);
for (const file of report.files) {
  const absolute = path.join(fixtureRoot, file.name);
  assert.equal(fileHash(absolute), file.sha256, `${file.name} hash`);
  assert.equal(fs.statSync(absolute).size, file.byteLength, `${file.name} byte length`);
}

const temporary = fs.mkdtempSync(path.join(os.tmpdir(), "m12-07b-obj-"));
try {
  const regeneratedReport = path.join(temporary, "desktop-fixtures.json");
  const result = spawnSync(blender, ["-b", "--factory-startup", "--python", generator, "--", temporary, regeneratedReport], {
    cwd: root,
    encoding: "utf8",
    maxBuffer: 20 * 1024 * 1024,
  });
  assert.equal(result.status, 0, `${result.stdout}\n${result.stderr}`);
  assert.deepEqual(readJson(regeneratedReport), report, "OBJ multi/negative report is not deterministic");
  for (const file of report.files) assert.deepEqual(fs.readFileSync(path.join(temporary, file.name)), fs.readFileSync(path.join(fixtureRoot, file.name)), `${file.name} bytes are not deterministic`);
}
finally {
  fs.rmSync(temporary, { recursive: true, force: true });
}

process.stdout.write(`obj-multi-negative-fixtures-ok objects=${report.semantic.objects.length} negative=true malformed=${report.malformedFace.expectedCode} textureOrigin=relative deterministic=true next=${manifest.nextTask}\n`);