import { Injectable } from "@nestjs/common";
import { ConfigService } from "@nestjs/config";
import type { Response } from "express";

type CookieOptionsInput = {
  httpOnly?: boolean;
  secure?: boolean;
  sameSite?: "lax" | "strict" | "none";
  maxAge?: number;
  expires?: Date;
  path?: string;
};

type CookieOptions = {
  httpOnly: boolean;
  secure: boolean;
  sameSite: "lax" | "strict";
  maxAge?: number;
  expires?: Date;
  path: string;
};

@Injectable()
export class CookieService {
  constructor(private readonly configService: ConfigService) {}

  private getCookieOptions(options?: CookieOptionsInput): CookieOptions {
    const isDevelopment =
      this.configService.get<string>("NODE_ENV") !== "production";
    const isSecure = options?.secure ?? !isDevelopment;

    const sameSiteOption = options?.sameSite;
    const defaultSameSite = isDevelopment ? "lax" : "strict";
    const sameSite =
      sameSiteOption === "none"
        ? defaultSameSite
        : (sameSiteOption ?? defaultSameSite);

    return {
      httpOnly: options?.httpOnly ?? true,
      secure: isSecure,
      sameSite,
      ...(options?.maxAge !== undefined && { maxAge: options.maxAge }),
      ...(options?.expires !== undefined && { expires: options.expires }),
      path: options?.path ?? "/",
    };
  }

  setCookie(
    res: Response,
    name: string,
    value: string,
    options?: CookieOptionsInput,
  ): void {
    const cookieOptions = this.getCookieOptions(options);
    res.cookie(name, value, cookieOptions);
  }

  clearCookie(res: Response, name: string, options?: CookieOptionsInput): void {
    const clearOptions = this.getCookieOptions({
      ...options,
      maxAge: 0,
      expires: new Date(0),
    });

    res.clearCookie(name, clearOptions);
    res.cookie(name, "", clearOptions);
  }
}