import { spawn } from "node:child_process";
import { stat } from "node:fs/promises";
import path from "node:path";
import { exists, loadRecipe, projectRoot, readJson, recipesRoot, workRoot, writeJson } from "./lib.mjs";

function run(executable, args) {
  return new Promise((resolve, reject) => {
    const child = spawn(executable, args, { cwd: projectRoot, stdio: "inherit", windowsHide: true });
    child.once("error", reject);
    child.once("exit", (code) => code === 0 ? resolve() : reject(new Error(`Blender exited with code ${code}.`)));
  });
}

export async function convertDungeonEnvironment(slug) {
  await loadRecipe(slug);
  const blender = path.resolve(process.env.BLENDER_BIN ?? path.join(projectRoot, "../wow335a/dungeon-export-work/tools/blender-5.0.1-windows-x64/blender.exe"));
  const addon = path.resolve(process.env.WOW_EXPORT_ADDON ?? path.join(projectRoot, "../wow335a/dungeon-export-work/tools/wow.export-0.2.19/addon"));
  const source = path.join(workRoot, slug, "source-export");
  const output = path.join(workRoot, slug, "staging", "environment");
  const blockers = [];
  if (!await exists(blender)) blockers.push("Blender was not found; set BLENDER_BIN.");
  if (!await exists(path.join(addon, "io_scene_wowobj"))) blockers.push("wow.export Blender addon was not found; set WOW_EXPORT_ADDON.");
  if (!await exists(source)) blockers.push("Recipe extraction output is missing; run dungeon:extract first.");
  if (blockers.length) {
    const report = { schemaVersion: 1, dungeonId: slug, status: "blocked", blockers };
    await writeJson(path.join(workRoot, slug, "conversion-report.json"), report);
    return report;
  }
  const reportFile = path.join(output, "conversion-report.json");
  const previousMtime = await exists(reportFile) ? (await stat(reportFile)).mtimeMs : 0;
  await run(blender, [
    "--background", "--factory-startup",
    "--python", path.join(projectRoot, "scripts/dungeon-pipeline/blender/convert-dungeon.py"),
    "--", path.join(recipesRoot, `${slug}.json`), source, output, addon,
  ]);
  if (!await exists(reportFile) || (await stat(reportFile)).mtimeMs <= previousMtime) {
    const report = { schemaVersion: 1, dungeonId: slug, status: "blocked", blockers: ["Blender exited without producing a fresh conversion report."] };
    await writeJson(path.join(workRoot, slug, "conversion-report.json"), report);
    return report;
  }
  return await readJson(reportFile);
}