package de.tims.tictactoe.ai;

import static org.mockito.Mockito.*;

import org.junit.jupiter.api.Test;
import org.junit.jupiter.api.extension.ExtendWith;
import org.mockito.ArgumentMatcher;
import org.mockito.Mock;
import org.mockito.junit.jupiter.MockitoExtension;

import de.tims.tictactoe.GameLogic;

@ExtendWith(MockitoExtension.class)
class AIEasyTest {
	static int size = 3;
	
	@Mock
	private GameLogic gl;

	@Test
	void emptyBoardChooseRandomField() {
		char realChar = 'o';
		doReturn(new char[][] { {'-', '-', '-'}, {'-', '-', '-'}, {'-', '-', '-'} }).when(gl).getBoard();
		
		TicTacToeAI ai = new AIEasy(gl);
		
		//run method 100 times, because of random generator
		for (int i = 0; i < 100; i++) {
			ai.calculateNextMove();
		}
			
		verify(gl, times(100)).setField(intThat(new ChooseRandomFieldMatcher()), intThat(new ChooseRandomFieldMatcher()), eq(realChar));
	}
	
	@Test
	void notEmptyBoardChooseRandomFreeField() {
		char realChar = 'o';
		doReturn(new char[][] { {'x', '-', 'o'}, {'-', 'o', '-'}, {'-', 'x', 'x'} }).when(gl).getBoard();
		
		TicTacToeAI ai = new AIEasy(gl);
		
		//run method 100 times, because of random generator
		for (int i = 0; i < 100; i++) {
			ai.calculateNextMove();
		}
			
		verify(gl, times(100)).setField(intThat(new ChooseRandomFieldMatcher()), intThat(new ChooseRandomFieldMatcher()), eq(realChar));
		//verify that the method is never called with a field which was already set
		verify(gl, never()).setField(0, 0, realChar);
		verify(gl, never()).setField(0, 2, realChar);
		verify(gl, never()).setField(1, 1, realChar);
		verify(gl, never()).setField(2, 1, realChar);
		verify(gl, never()).setField(2, 2, realChar);
	}
	
	private static class ChooseRandomFieldMatcher implements ArgumentMatcher<Integer> {
		@Override
		public boolean matches(Integer argument) {
			return argument.intValue() >= 0 && argument.intValue() < size;
		}
	}
}