import { describe, expect, it } from '@jest/globals';
import { _ } from '../src/core';
import { fromChar as _c } from '../src/char';
import { toString as $s, fromString as _s } from '../src/string';
import { run } from '../src/bf';

describe('BF', () => {
  describe('run', () => {
    it('handles output command', () => {
      expect($s(run(_s('.'))(_s('')))).toBe(String.fromCharCode(0));
    });

    it('handles input command', () => {
      expect($s(run(_s(',.'))(_s('a')))).toBe('a');
    });

    it('handles inc command', () => {
      expect($s(run(_s('+.'))(_s('')))).toBe(String.fromCharCode(1));
    });

    it('handles dec command', () => {
      expect($s(run(_s('-.'))(_s('')))).toBe(String.fromCharCode(255));
    });

    it('handles next command', () => {
      expect($s(run(_s('+++++>++.'))(_s('')))).toBe(String.fromCharCode(2));
    });

    it('handles prev command', () => {
      expect($s(run(_s('+++++>++<+++++.'))(_s('')))).toBe(String.fromCharCode(10));
    });

    it('skips loop block on zero', () => {
      expect($s(run(_s('[+++++].'))(_s('')))).toBe(String.fromCharCode(0));
    });

    it('repeats loop block while not zero', () => {
      expect($s(run(_s('+++++[-].'))(_s('')))).toBe(String.fromCharCode(0));
    });

    it('prints "Hello World!"', () => {
      expect($s(run
        (_s('++++++++[>++++[>++>+++>+++>+<<<<-]>+>+>->>+[<]<-]>>.>---.+++++++..+++.>>.<-.<.+++.------.--------.>>+.>++.'))
        (_s(''))))
        .toBe('Hello World!\n');
    });
  });
});