package layout_test

import (
	"testing"

	"github.com/nebara/nebara-os/internal/ui/layout"
)

func TestCalculate_Normal(t *testing.T) {
	c := layout.Calculate(120, 40)
	if c.IsMinimum {
		t.Error("120×40 should not be minimum")
	}
	if c.ContentWidth <= 0 {
		t.Error("ContentWidth should be positive")
	}
	if c.MarginH <= 0 {
		t.Error("MarginH should be positive")
	}
	if c.ContentWidth != c.TermWidth-c.MarginH*2 {
		t.Errorf("ContentWidth mismatch: got %d, expected %d", c.ContentWidth, c.TermWidth-c.MarginH*2)
	}
}

func TestCalculate_TooSmall(t *testing.T) {
	c := layout.Calculate(40, 10)
	if !c.IsMinimum {
		t.Error("40×10 should be flagged as minimum/too-small")
	}
}

func TestCalculate_BoundaryMinWidth(t *testing.T) {
	c := layout.Calculate(layout.MinWidth, layout.MinHeight)
	if c.IsMinimum {
		t.Errorf("exact minimum %dx%d should not be flagged as too small", layout.MinWidth, layout.MinHeight)
	}
}

func TestCalculate_MarginClamps(t *testing.T) {
	// Very wide terminal: margin should not exceed 12.
	cWide := layout.Calculate(400, 80)
	if cWide.MarginH > 12 {
		t.Errorf("MarginH should not exceed 12 on very wide terminal, got %d", cWide.MarginH)
	}

	// Narrow but valid terminal: margin should not go below 4.
	cNarrow := layout.Calculate(60, 20)
	if cNarrow.MarginH < 4 {
		t.Errorf("MarginH should be at least 4 on narrow terminal, got %d", cNarrow.MarginH)
	}
}

func TestCalculate_MessageVisibility(t *testing.T) {
	cCompact := layout.Calculate(80, 23)
	if cCompact.MessageVisible {
		t.Error("message should be hidden on terminals shorter than 24 rows")
	}
	cNormal := layout.Calculate(80, 24)
	if !cNormal.MessageVisible {
		t.Error("message should be visible at 24 rows")
	}
}

func TestCalculate_MenuInnerPad(t *testing.T) {
	cNarrow := layout.Calculate(80, 24)
	if cNarrow.MenuInnerPad != 1 {
		t.Errorf("expected menu inner pad 1 for narrow terminal, got %d", cNarrow.MenuInnerPad)
	}
	cWide := layout.Calculate(120, 40)
	if cWide.MenuInnerPad != 2 {
		t.Errorf("expected menu inner pad 2 for wide terminal, got %d", cWide.MenuInnerPad)
	}
}