package invoice

import "testing"

func TestParseQuantity(t *testing.T) {
	cases := []struct {
		input string
		want  Quantity
	}{
		{"1", 100},
		{"0.5", 50},
		{"2,25", 225},
		{"10.00", 1000},
	}
	for _, tc := range cases {
		got, err := ParseQuantity(tc.input)
		if err != nil {
			t.Fatalf("ParseQuantity(%q) unexpected error: %v", tc.input, err)
		}
		if got != tc.want {
			t.Fatalf("ParseQuantity(%q)=%v want %v", tc.input, got, tc.want)
		}
	}
}

func TestFormatQuantity(t *testing.T) {
	cases := []struct {
		input Quantity
		want  string
	}{
		{100, "1"},
		{50, "0.5"},
		{225, "2.25"},
		{1010, "10.1"},
	}
	for _, tc := range cases {
		got := FormatQuantity(tc.input)
		if got != tc.want {
			t.Fatalf("FormatQuantity(%v)=%q want %q", tc.input, got, tc.want)
		}
	}
}

func TestLineAmountNegative(t *testing.T) {
	item := Item{
		UnitPrice: -29500,
		Quantity:  100,
	}
	if got := LineAmount(item); got != -29500 {
		t.Fatalf("LineAmount negative mismatch: %v", got)
	}
}