import { FacadeHandlerError, FacadeRequest, FacadeResponse, FacadeSerialQueue, createFailure, createRequest, isFacadeRequest } from "./facade-envelope.js";
import type { OpenScadKernelModule } from "./openscad-inspect-facade.js";

export const OPENSCAD_IMPORT_DXF_SCHEMA = "freecad-web-openscad/import-dxf/v1" as const;
export const OPENSCAD_IMPORT_DXF_COMMAND = "openscad.importDxf" as const;

export interface OpenScadImportDxfPayload { schema: typeof OPENSCAD_IMPORT_DXF_SCHEMA; module: "OpenSCAD"; documentId: string; path: string; layer?: string; }
export interface OpenScadImportDxfResult { schema: typeof OPENSCAD_IMPORT_DXF_SCHEMA; module: "OpenSCAD"; documentId: string; documentHandle: string; createdDocument: boolean; objectNames: string[]; objectCount: number; faceCount: number; recomputed: true; sourceEntry: string; resourcesReleased: true; }
export type OpenScadImportDxfRequest = FacadeRequest<OpenScadImportDxfPayload>;

export function createOpenScadImportDxfRequest(requestId: string, payload: OpenScadImportDxfPayload): OpenScadImportDxfRequest {
  return createRequest(requestId, OPENSCAD_IMPORT_DXF_COMMAND, payload, payload.documentId);
}

export function isOpenScadImportDxfRequest(value: unknown): value is OpenScadImportDxfRequest {
  if (!isFacadeRequest(value)) return false;
  const request = value as OpenScadImportDxfRequest;
  const payload = request.payload;
  return request.command === OPENSCAD_IMPORT_DXF_COMMAND && payload?.schema === OPENSCAD_IMPORT_DXF_SCHEMA && payload?.module === "OpenSCAD"
    && typeof payload.documentId === "string" && payload.documentId.length > 0 && typeof payload.path === "string" && payload.path.length > 0
    && (payload.layer === undefined || typeof payload.layer === "string");
}

export async function dispatchOpenScadImportDxf(queue: FacadeSerialQueue, request: OpenScadImportDxfRequest, kernelSource: OpenScadKernelModule | Promise<OpenScadKernelModule>): Promise<FacadeResponse<OpenScadImportDxfResult>> {
  const requestId = request.requestId;
  if (!isOpenScadImportDxfRequest(request)) return createFailure(requestId, "invalid_request", "OpenSCAD DXF import envelope is invalid");
  return queue.dispatch(request, async (payload, signal) => {
    if (signal.aborted) throw new FacadeHandlerError("cancelled", "request was cancelled");
    const kernel = await kernelSource;
    const raw = String(kernel.ccall("fc_web_dispatch_json", "string", ["string"], [JSON.stringify({ cmd: OPENSCAD_IMPORT_DXF_COMMAND, args: payload })]));
    let reply: Record<string, unknown>;
    try { reply = JSON.parse(raw) as Record<string, unknown>; } catch { throw new FacadeHandlerError("native_protocol_error", "OpenSCAD native dispatcher returned invalid JSON"); }
    if (reply.ok !== true) throw new FacadeHandlerError(String(reply.code || "import_failed"), String(reply.error || "OpenSCAD DXF import failed"));
    if (reply.schema !== OPENSCAD_IMPORT_DXF_SCHEMA || reply.module !== "OpenSCAD" || reply.documentId !== payload.documentId
      || typeof reply.documentHandle !== "string" || !reply.documentHandle || typeof reply.createdDocument !== "boolean"
      || !Array.isArray(reply.objectNames) || reply.objectNames.some((name) => typeof name !== "string" || !name)
      || reply.objectCount !== reply.objectNames.length || typeof reply.faceCount !== "number" || !Number.isInteger(reply.faceCount) || reply.faceCount < 0
      || reply.faceCount !== reply.objectCount || typeof reply.sourceEntry !== "string" || reply.sourceEntry.length === 0
      || reply.recomputed !== true || reply.resourcesReleased !== true) {
      throw new FacadeHandlerError("native_protocol_error", "OpenSCAD DXF import returned an invalid result schema");
    }
    return reply as unknown as OpenScadImportDxfResult;
  });
}