import sqlEqualityParser from "../../../utils/sql-equality-parser";
import { ServerQueryEqualities } from "../../../types";

type Params = {
    fieldName: string;
    value?: string;
    equality?: (typeof ServerQueryEqualities)[number];
};

type Return = {
    str?: string;
    param?: string;
};

/**
 * # SQL Gen Operator Gen
 * @description Generates an SQL operator for node module `mysql` or `serverless-mysql`
 */
export default function sqlGenOperatorGen({
    fieldName,
    value,
    equality,
}: Params): Return {
    if (value) {
        if (equality == "LIKE") {
            return {
                str: `LOWER(${fieldName}) LIKE LOWER('%${value}%')`,
            };
        } else if (equality == "LIKE_RAW") {
            return {
                str: `LOWER(${fieldName}) LIKE LOWER(?)`,
                param: value,
            };
        } else if (equality == "NOT LIKE") {
            return {
                str: `LOWER(${fieldName}) NOT LIKE LOWER('%${value}%')`,
            };
        } else if (equality == "NOT LIKE_RAW") {
            return {
                str: `LOWER(${fieldName}) NOT LIKE LOWER(?)`,
                param: value,
            };
        } else if (equality == "REGEXP") {
            return {
                str: `LOWER(${fieldName}) REGEXP LOWER(?')`,
                param: value,
            };
        } else if (equality == "FULLTEXT") {
            return {
                str: `MATCH(${fieldName}) AGAINST(? IN BOOLEAN MODE)`,
                param: value,
            };
        } else if (equality == "NOT EQUAL") {
            return {
                str: `${fieldName} != ?`,
                param: value,
            };
        } else if (equality) {
            return {
                str: `${fieldName} ${sqlEqualityParser(equality)} ?`,
                param: value,
            };
        } else {
            return {
                str: `${fieldName} = ?`,
                param: value,
            };
        }
    } else {
        if (equality == "IS NULL") {
            return { str: `${fieldName} IS NULL` };
        } else if (equality == "IS NOT NULL") {
            return { str: `${fieldName} IS NOT NULL` };
        } else if (equality) {
            return {
                str: `${fieldName} ${sqlEqualityParser(equality)} ?`,
                param: value,
            };
        } else {
            return {
                str: `${fieldName} = ?`,
                param: value,
            };
        }
    }
}