import { Injectable, NotFoundException } from "@nestjs/common";
import { Prisma, PrismaClient } from "@prisma/client";
import { PrismaService } from "src/prisma/prisma.service";

type Tx = Prisma.TransactionClient | PrismaClient;

@Injectable()
export class FullNameResolver {
    constructor(private readonly prisma: PrismaService){}

    readonly resolveFullName = async (employee_id: number, client?: Tx): Promise<string> =>{
        const db = client ?? this.prisma;
        const employee = await db.employees.findUnique({
            where: { id: employee_id },
            select: { user: { select: {first_name: true, last_name: true} } },
        });
        if(!employee) throw new NotFoundException(`Unknown user with name: ${employee_id}`)

        const full_name = ( employee.user.first_name + " " + employee.user.last_name ) || " ";
        return full_name;
    }
}