switch hto monorepo structure

backend/internal/server/brightness/ddc_test.go

@@ -0,0 +1,135 @@
+package brightness
+
+import (
+	"testing"
+)
+
+func TestDDCBackend_PercentConversions(t *testing.T) {
+	tests := []struct {
+		name      string
+		max       int
+		percent   int
+		wantValue int
+	}{
+		{
+			name:      "0% should map to minValue=1",
+			max:       100,
+			percent:   0,
+			wantValue: 1,
+		},
+		{
+			name:      "1% should be 1",
+			max:       100,
+			percent:   1,
+			wantValue: 1,
+		},
+		{
+			name:      "50% should be ~50",
+			max:       100,
+			percent:   50,
+			wantValue: 50,
+		},
+		{
+			name:      "100% should be max",
+			max:       100,
+			percent:   100,
+			wantValue: 100,
+		},
+	}
+
+	b := &DDCBackend{}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			got := b.percentToValue(tt.percent, tt.max, false)
+			diff := got - tt.wantValue
+			if diff < 0 {
+				diff = -diff
+			}
+			if diff > 1 {
+				t.Errorf("percentToValue() = %v, want %v (±1)", got, tt.wantValue)
+			}
+		})
+	}
+}
+
+func TestDDCBackend_ValueToPercent(t *testing.T) {
+	tests := []struct {
+		name        string
+		max         int
+		value       int
+		wantPercent int
+		tolerance   int
+	}{
+		{
+			name:        "zero value should be 1%",
+			max:         100,
+			value:       0,
+			wantPercent: 1,
+			tolerance:   0,
+		},
+		{
+			name:        "min value should be 1%",
+			max:         100,
+			value:       1,
+			wantPercent: 1,
+			tolerance:   0,
+		},
+		{
+			name:        "mid value should be ~50%",
+			max:         100,
+			value:       50,
+			wantPercent: 50,
+			tolerance:   2,
+		},
+		{
+			name:        "max value should be 100%",
+			max:         100,
+			value:       100,
+			wantPercent: 100,
+			tolerance:   0,
+		},
+	}
+
+	b := &DDCBackend{}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			got := b.valueToPercent(tt.value, tt.max, false)
+			diff := got - tt.wantPercent
+			if diff < 0 {
+				diff = -diff
+			}
+			if diff > tt.tolerance {
+				t.Errorf("valueToPercent() = %v, want %v (±%d)", got, tt.wantPercent, tt.tolerance)
+			}
+		})
+	}
+}
+
+func TestDDCBackend_RoundTrip(t *testing.T) {
+	b := &DDCBackend{}
+
+	tests := []struct {
+		name    string
+		max     int
+		percent int
+	}{
+		{"1%", 100, 1},
+		{"25%", 100, 25},
+		{"50%", 100, 50},
+		{"75%", 100, 75},
+		{"100%", 100, 100},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			value := b.percentToValue(tt.percent, tt.max, false)
+			gotPercent := b.valueToPercent(value, tt.max, false)
+
+			if diff := tt.percent - gotPercent; diff < -1 || diff > 1 {
+				t.Errorf("round trip failed: wanted %d%%, got %d%% (value=%d)", tt.percent, gotPercent, value)
+			}
+		})
+	}
+}