import type { DboBuilder } from "../DboBuilder/DboBuilder";
import type { OnSchemaChangeCallback } from "./SchemaWatch";

export type ValidatedWatchSchemaType =
  | { watchType: "NONE" }
  | { watchType: "DDL_trigger"; onChange?: OnSchemaChangeCallback }
  | {
      watchType: "prostgles_queries";
      onChange?: OnSchemaChangeCallback;
      isFallbackFromDDL: boolean;
    };

export const getValidatedWatchSchemaType = (
  dboBuilder: DboBuilder,
): ValidatedWatchSchemaType => {
  const { watchSchema, watchSchemaType, tsGeneratedTypesDir, disableRealtime } =
    dboBuilder.prostgles.opts;
  if (!watchSchema) return { watchType: "NONE" };

  if (watchSchema === "hotReloadMode" && !tsGeneratedTypesDir) {
    throw "tsGeneratedTypesDir option is needed for watchSchema: hotReloadMode to work ";
  }

  const onChange = typeof watchSchema === "function" ? watchSchema : undefined;

  if (watchSchemaType === "DDL_trigger" || !watchSchemaType) {
    if (!dboBuilder.prostgles.isSuperUser || disableRealtime) {
      if (watchSchemaType === "DDL_trigger") {
        console.error(
          `watchSchemaType "DDL_trigger" cannot be used because db user is not a superuser. Will fallback to watchSchemaType "prostgles_queries" `,
        );
      } else {
        console.warn(
          `watchSchema fallback to watchSchemaType "prostgles_queries" due to ${disableRealtime ? "disableRealtime setting" : "non-superuser"}`,
        );
      }
      return {
        watchType: "prostgles_queries",
        onChange,
        isFallbackFromDDL: true,
      };
    }

    return {
      watchType: "DDL_trigger",
      onChange,
    };
  }

  return {
    watchType: watchSchemaType,
    isFallbackFromDDL: false,
    onChange,
  };
};