import { Context, Effect, Layer } from "effect";
import * as bcrypt from "bcrypt";
import { AuthError, ValidationError } from "../../../shared/types.js";

const SALT_ROUNDS = 12;

export class PasswordService extends Context.Tag("PasswordService")<
  PasswordService,
  {
    readonly hash: (password: string) => Effect.Effect<string, AuthError>;
    readonly verify: (
      password: string,
      hash: string
    ) => Effect.Effect<boolean, AuthError>;
    readonly validatePasswordStrength: (
      password: string
    ) => Effect.Effect<void, ValidationError>;
  }
>() {
  static Live = Layer.succeed(
    this,
    {
      hash: (password: string) =>
        Effect.tryPromise({
          try: () => bcrypt.hash(password, SALT_ROUNDS),
          catch: (error) =>
            new AuthError(
              "HASH_FAILED",
              "Failed to hash password",
              error
            ),
        }),

      verify: (password: string, hash: string) =>
        Effect.tryPromise({
          try: () => bcrypt.compare(password, hash),
          catch: (error) =>
            new AuthError(
              "VERIFY_FAILED",
              "Failed to verify password",
              error
            ),
        }),

      validatePasswordStrength: (password: string) =>
        Effect.gen(function* () {
          if (password.length < 8) {
            return yield* Effect.fail(
              new ValidationError(
                "password",
                "Password must be at least 8 characters long"
              )
            );
          }

          if (!/[A-Z]/.test(password)) {
            return yield* Effect.fail(
              new ValidationError(
                "password",
                "Password must contain at least one uppercase letter"
              )
            );
          }

          if (!/[a-z]/.test(password)) {
            return yield* Effect.fail(
              new ValidationError(
                "password",
                "Password must contain at least one lowercase letter"
              )
            );
          }

          if (!/[0-9]/.test(password)) {
            return yield* Effect.fail(
              new ValidationError(
                "password",
                "Password must contain at least one number"
              )
            );
          }
        }),
    }
  );
}