import _ from "lodash";
import { APIPathsCrudParams, APIPathsParamsAllowedTable } from "../../types";

export default async function checks<
    T extends { [k: string]: any } = { [k: string]: any }
>({
    table,
    allowedTables,
    query,
    body,
    method,
    getMiddleware,
    postMiddleware,
    putMiddleware,
    deleteMiddleware,
    crudMiddleware,
}: APIPathsCrudParams<T>): Promise<
    Pick<APIPathsCrudParams<T>, "query" | "body"> & {
        allowedTable: APIPathsParamsAllowedTable;
    }
> {
    const allowedTable = allowedTables.find((tbl) => tbl.table == table);

    if (!allowedTable) {
        throw new Error(`Can't Access this table: \`${table}\``);
    }

    let newQuery = _.cloneDeep(query);
    let newBody = _.cloneDeep(body);

    const searchFields = Object.keys(newQuery?.searchQuery?.query || {});
    const selectFields = (
        newQuery?.searchQuery?.selectFields
            ? newQuery.searchQuery.selectFields.map((f) =>
                  typeof f == "string"
                      ? f
                      : typeof f == "object"
                      ? f.fieldName
                      : undefined
              )
            : undefined
    )?.filter((f) => typeof f == "string");

    const targetFields = [...(searchFields || []), ...(selectFields || [])];

    if (method == "GET" && allowedTable.allowedFields) {
        for (let i = 0; i < targetFields.length; i++) {
            const fld = targetFields[i];
            const allowedFld = allowedTable.allowedFields.find((f) =>
                typeof f == "string" ? f == fld : fld.match(f)
            );

            if (!allowedFld) {
                throw new Error(`\`${allowedFld}\` field not allowed`);
            }
        }
    }

    if (method == "GET" && allowedTable.disallowedFields) {
        for (let i = 0; i < targetFields.length; i++) {
            const fld = targetFields[i];
            const disallowedFld = allowedTable.disallowedFields.find((f) =>
                typeof f == "string" ? f == fld : fld.match(f)
            );

            if (disallowedFld) {
                throw new Error(`\`${disallowedFld}\` field not allowed`);
            }
        }
    }

    if (method == "GET" && getMiddleware) {
        newQuery = await getMiddleware({ query: newQuery || ({} as any) });
    }

    if (method !== "GET" && crudMiddleware) {
        const middRes = await crudMiddleware({
            body: newBody || ({} as any),
            query: newQuery || {},
        });

        newBody = _.merge(newBody, middRes);
    }

    if (method == "POST" && postMiddleware) {
        const middRes = await postMiddleware({
            body: newBody || ({} as any),
            query: newQuery || {},
        });

        newBody = _.merge(newBody, middRes);
    }

    if (method == "PUT" && putMiddleware) {
        const middRes = await putMiddleware({
            body: newBody || ({} as any),
            query: newQuery || {},
        });

        newBody = _.merge(newBody, middRes);
    }

    if (method == "DELETE" && deleteMiddleware) {
        const middRes = await deleteMiddleware({
            body: newBody || ({} as any),
            query: newQuery || {},
        });

        newBody = _.merge(newBody, middRes);
    }

    if (newQuery?.searchQuery?.join) {
        for (let i = 0; i < newQuery.searchQuery.join.length; i++) {
            const join = newQuery.searchQuery.join[i];
            const joinTableName = join.tableName;
            const selectFields = join.selectFields;

            if (allowedTables?.[0]) {
                const allowedJoinTable = allowedTables.find(
                    (t) => t.table == joinTableName
                );

                if (!allowedJoinTable?.table) {
                    throw new Error(`Can't joint \`${joinTableName}\` table`);
                }

                const allowedFields = allowedJoinTable.allowedFields;
                const disallowedFields = allowedJoinTable.disallowedFields;

                if (selectFields?.[0]) {
                    for (let j = 0; j < selectFields.length; j++) {
                        const selectField = selectFields[j];
                        const selectFieldName =
                            typeof selectField == "object"
                                ? selectField.field
                                : String(selectField);

                        if (
                            allowedFields?.[0] &&
                            !allowedFields.find(
                                (f) => String(f) == selectFieldName
                            )
                        ) {
                            throw new Error(`Can't Select this Field!`);
                        }

                        if (
                            disallowedFields?.[0] &&
                            disallowedFields.find(
                                (f) => String(f) == selectFieldName
                            )
                        ) {
                            throw new Error(`Disallowed Field Selected!`);
                        }
                    }
                }
            }
        }
    }

    return {
        query: newQuery,
        body: newBody,
        allowedTable,
    };
}