package grid

import (
	"testing"
)

func TestHex_NeighborAt(t *testing.T) {
	testCases := []struct {
		name      string
		hex       Hex
		direction int
		want      Hex
	}{
		{
			name:      "zero hex zero direction",
			hex:       Hex{},
			direction: 0,
			want:      NewHex(1, 0),
		},
		{
			name:      "zero hex direction 1",
			hex:       Hex{},
			direction: 1,
			want:      NewHex(0, 1),
		},
		{
			name:      "zero hex direction 2",
			hex:       Hex{},
			direction: 2,
			want:      NewHex(-1, 1),
		},
		{
			name:      "zero hex direction 3",
			hex:       Hex{},
			direction: 3,
			want:      NewHex(-1, 0),
		},
		{
			name:      "zero hex direction 4",
			hex:       Hex{},
			direction: 4,
			want:      NewHex(0, -1),
		},
		{
			name:      "zero hex zero direction 5",
			hex:       Hex{},
			direction: 5,
			want:      NewHex(1, -1),
		},
		{
			name:      "zero hex zero direction overflow",
			hex:       Hex{},
			direction: 6,
			want:      NewHex(1, 0),
		},
		{
			name:      "zero hex zero direction overflow twice",
			hex:       Hex{},
			direction: 12,
			want:      NewHex(1, 0),
		},
		{
			name:      "zero hex zero direction underflow",
			hex:       Hex{},
			direction: -1,
			want:      NewHex(1, -1),
		},
		{
			name:      "zero hex zero direction underflow twice",
			hex:       Hex{},
			direction: -7,
			want:      NewHex(1, -1),
		},
	}
	for _, tc := range testCases {
		t.Run(tc.name, func(t *testing.T) {
			got := tc.hex.NeighborAt(tc.direction)
			if tc.want != got {
				t.Fatalf("want %v but got %v", tc.want, got)
			}
		})
	}
}