import { loadTextFile } from "./file-service.js";
import {
  machineIniPath,
  parameterFilePath,
  toolTablePath,
} from "./path-model.js";
import { restoreMachineParametersFromOpfs } from "./linuxcnc-parameter-bridge.js";
import { loadMachineToolTableFromOpfs } from "./linuxcnc-tool-table-bridge.js";

const DEFAULT_WASM_INI_PATH = "/work/machine.ini";
const DEFAULT_WASM_PARAMETER_PATH = "/work/linuxcnc.var";
const DEFAULT_WASM_TOOL_TABLE_PATH = "/work/tool.tbl";

function requireSessionSdk(interp) {
  if (typeof interp?.writeTextFile !== "function") {
    throw new Error("interpreter SDK is missing writeTextFile().");
  }
}

function resolveSessionPaths(machineId, options = {}) {
  return {
    iniOpfsPath: options.iniOpfsPath ?? machineIniPath(machineId, options.iniFilename),
    iniWasmPath: options.iniWasmPath ?? DEFAULT_WASM_INI_PATH,
    parameterOpfsPath:
      options.parameterOpfsPath ?? parameterFilePath(machineId, options.parameterFilename),
    parameterWasmPath: options.parameterWasmPath ?? DEFAULT_WASM_PARAMETER_PATH,
    toolTableOpfsPath:
      options.toolTableOpfsPath ?? toolTablePath(machineId, options.toolTableFilename),
    toolTableWasmPath: options.toolTableWasmPath ?? DEFAULT_WASM_TOOL_TABLE_PATH,
  };
}

export async function loadMachineSessionFromOpfs(interp, machineId, options = {}) {
  requireSessionSdk(interp);
  const paths = resolveSessionPaths(machineId, options);
  const iniText = await loadTextFile(paths.iniOpfsPath, options.storage);
  interp.writeTextFile(paths.iniWasmPath, iniText);

  const parameters = await restoreMachineParametersFromOpfs(interp, machineId, {
    storage: options.storage,
    opfsPath: paths.parameterOpfsPath,
    wasmPath: paths.parameterWasmPath,
  });
  const toolTable = await loadMachineToolTableFromOpfs(interp, machineId, {
    storage: options.storage,
    opfsPath: paths.toolTableOpfsPath,
    wasmPath: paths.toolTableWasmPath,
    randomToolChanger: options.randomToolChanger === true,
  });

  return {
    machineId,
    ini: {
      opfsPath: paths.iniOpfsPath,
      wasmPath: paths.iniWasmPath,
    },
    parameters,
    toolTable,
  };
}