// @flow
import type { Plugin } from "graphile-build";

export default (function PgMutationProceduresPlugin(builder) {
  builder.hook(
    "GraphQLObjectType:fields",
    (fields, build, context) => {
      const {
        extend,
        pgIntrospectionResultsByKind: introspectionResultsByKind,
        inflection,
        pgMakeProcField: makeProcField,
        pgOmit: omit,
        swallowError,
        describePgEntity,
        sqlCommentByAddingTags,
      } = build;
      const {
        scope: { isRootMutation },
        fieldWithHooks,
      } = context;

      if (!isRootMutation) {
        return fields;
      }

      return extend(
        fields,
        introspectionResultsByKind.procedure.reduce((memo, proc) => {
          // PERFORMANCE: These used to be .filter(...) calls
          if (proc.isStable) return memo;
          if (!proc.namespace) return memo;
          if (omit(proc, "execute")) return memo;

          const fieldName = inflection.functionMutationName(proc);
          try {
            memo = extend(
              memo,
              {
                [fieldName]: makeProcField(fieldName, proc, build, {
                  fieldWithHooks,
                  isMutation: true,
                }),
              },
              `Adding mutation field for ${describePgEntity(
                proc
              )}. You can rename this field with a 'Smart Comment':\n\n  ${sqlCommentByAddingTags(
                proc,
                {
                  name: "newNameHere",
                }
              )}`
            );
          } catch (e) {
            swallowError(e);
          }
          return memo;
        }, {}),
        `Adding mutation procedure to root Mutation field`
      );
    },
    ["PgMutationProcedures"]
  );
}: Plugin);