tiki/view/header/header_layout_test.go

package header

import (
	"testing"

	"github.com/boolean-maybe/tiki/model"
)

// --- pure layout function tests ---

func TestCalculateHeaderLayout_chartVisibleAtThreshold(t *testing.T) {
	// availableBetween = 119 - 30 - 25 = 64
	// requiredContext = max(10, 40) = 40
	// required for chart = 40 + 10 + 14 = 64 → exactly fits
	layout := CalculateHeaderLayout(119, 10)
	if !layout.ChartVisible {
		t.Fatal("expected chart visible at width=119, contextHelp=10")
	}
}

func TestCalculateHeaderLayout_chartHiddenJustBelow(t *testing.T) {
	// availableBetween = 118 - 30 - 25 = 63 < 64
	layout := CalculateHeaderLayout(118, 10)
	if layout.ChartVisible {
		t.Fatal("expected chart hidden at width=118, contextHelp=10")
	}
}

func TestCalculateHeaderLayout_chartThresholdGrowsWithContextHelp(t *testing.T) {
	// contextHelpWidth=60 already >= MinContextWidth so requiredContext=60
	// required = 60 + 10 + 14 = 84; availableBetween must be >= 84
	// totalWidth = 84 + 30 + 25 = 139
	layout := CalculateHeaderLayout(139, 60)
	if !layout.ChartVisible {
		t.Fatal("expected chart visible at width=139, contextHelp=60")
	}
	layout = CalculateHeaderLayout(138, 60)
	if layout.ChartVisible {
		t.Fatal("expected chart hidden at width=138, contextHelp=60")
	}
}

func TestCalculateHeaderLayout_contextWidthWithChart(t *testing.T) {
	// width=200, contextHelp=50
	// availableBetween = 200 - 30 - 25 = 145
	// requiredContext = 50, chart required = 50+10+14 = 74 <= 145 → chart visible
	// maxContextWidth = 145 - (10+14) = 121; contextWidth = min(50, 121) = 50
	layout := CalculateHeaderLayout(200, 50)
	if !layout.ChartVisible {
		t.Fatal("expected chart visible")
	}
	if layout.ContextWidth != 50 {
		t.Errorf("contextWidth = %d, want 50", layout.ContextWidth)
	}
}

func TestCalculateHeaderLayout_contextWidthClampedByAvailable(t *testing.T) {
	// width=100, contextHelp=200 (too wide)
	// availableBetween = 100 - 30 - 25 = 45
	// requiredContext = 200; chart required = 214 > 45 → chart hidden
	// maxContextWidth = 45; contextWidth clamped to 45
	layout := CalculateHeaderLayout(100, 200)
	if layout.ChartVisible {
		t.Fatal("expected chart hidden when context too wide")
	}
	if layout.ContextWidth != 45 {
		t.Errorf("contextWidth = %d, want 45", layout.ContextWidth)
	}
}

func TestCalculateHeaderLayout_contextWidthFlooredAtMinContextWidth(t *testing.T) {
	// contextHelpWidth=10 < MinContextWidth=40, so requiredContext=40
	// but contextWidth itself stays at 10 (the floor only affects chart threshold)
	layout := CalculateHeaderLayout(200, 10)
	if layout.ContextWidth != 10 {
		t.Errorf("contextWidth = %d, want 10 (min floor only affects chart threshold)", layout.ContextWidth)
	}
}

func TestCalculateHeaderLayout_zeroContextHelp(t *testing.T) {
	// contextHelpWidth=0: requiredContext stays 0 (guard: > 0 check)
	// required for chart = 0 + 10 + 14 = 24
	// availableBetween at width=119 = 64 >= 24 → chart visible
	layout := CalculateHeaderLayout(119, 0)
	if !layout.ChartVisible {
		t.Fatal("expected chart visible with zero-width context help")
	}
	if layout.ContextWidth != 0 {
		t.Errorf("contextWidth = %d, want 0", layout.ContextWidth)
	}
}

func TestCalculateHeaderLayout_negativeContextHelp(t *testing.T) {
	layout := CalculateHeaderLayout(200, -5)
	if layout.ContextWidth != 0 {
		t.Errorf("contextWidth = %d, want 0 for negative input", layout.ContextWidth)
	}
}

func TestCalculateHeaderLayout_veryNarrowTerminal(t *testing.T) {
	// width < StatsWidth + LogoWidth → availableBetween clamped to 0
	// chart cannot be visible; contextWidth = 0
	layout := CalculateHeaderLayout(40, 30)
	if layout.ChartVisible {
		t.Fatal("expected chart hidden on very narrow terminal")
	}
	if layout.ContextWidth != 0 {
		t.Errorf("contextWidth = %d, want 0 on very narrow terminal", layout.ContextWidth)
	}
}

func TestCalculateHeaderLayout_exactlyStatsAndLogo(t *testing.T) {
	// width = StatsWidth + LogoWidth = 55 → availableBetween = 0
	layout := CalculateHeaderLayout(StatsWidth+LogoWidth, 10)
	if layout.ChartVisible {
		t.Fatal("expected chart hidden when no space between stats and logo")
	}
	if layout.ContextWidth != 0 {
		t.Errorf("contextWidth = %d, want 0", layout.ContextWidth)
	}
}

func TestCalculateHeaderLayout_chartHiddenContextFillsAvailable(t *testing.T) {
	// chart hidden; contextWidth should use full availableBetween
	// width=118, contextHelp=63
	// availableBetween = 63; chart requires 40+24=64 > 63 → hidden
	// maxContextWidth = 63; contextWidth = min(63, 63) = 63
	layout := CalculateHeaderLayout(118, 63)
	if layout.ChartVisible {
		t.Fatal("expected chart hidden")
	}
	if layout.ContextWidth != 63 {
		t.Errorf("contextWidth = %d, want 63", layout.ContextWidth)
	}
}

// --- integration tests (require widget construction) ---

func TestHeaderWidget_chartVisibilityThreshold_default(t *testing.T) {
	headerConfig := model.NewHeaderConfig()
	h := NewHeaderWidget(headerConfig)
	defer h.Cleanup()

	h.contextHelp.width = 10
	h.rebuildLayout(119)
	if !h.chartVisible {
		t.Fatalf("expected chart visible at width=119")
	}
	h.rebuildLayout(118)
	if h.chartVisible {
		t.Fatalf("expected chart hidden at width=118")
	}
}

func TestHeaderWidget_chartVisibilityThreshold_growsWithContextHelp(t *testing.T) {
	headerConfig := model.NewHeaderConfig()
	h := NewHeaderWidget(headerConfig)
	defer h.Cleanup()

	h.contextHelp.width = 60

	h.rebuildLayout(138)
	if h.chartVisible {
		t.Fatalf("expected chart hidden at width=138 for context=60")
	}

	h.rebuildLayout(139)
	if !h.chartVisible {
		t.Fatalf("expected chart visible at width=139 for context=60")
	}
}