feat: add navigation and window size handlers with corresponding tests

internal/handlers/rightNavigationHandler_test.go

@@ -0,0 +1,106 @@
+package handlers_test
+
+import (
+	"slices"
+	"testing"
+
+	"github.com/StevanFreeborn/term-tier/internal/core"
+	"github.com/StevanFreeborn/term-tier/internal/handlers"
+	"github.com/StevanFreeborn/term-tier/internal/state"
+	tea "github.com/charmbracelet/bubbletea"
+)
+
+func TestNewRightNavigationHandler(t *testing.T) {
+	h := handlers.NewRightNavigationHandler()
+
+	if h.Description() != "Move right" {
+		t.Errorf("Expected description 'Move right', got %q", h.Description())
+	}
+
+	keys := h.KeysHandled()
+
+	if !slices.Contains(keys, "right") || !slices.Contains(keys, "l") {
+		t.Errorf("Expected keys ['right', 'l'], got %v", keys)
+	}
+}
+
+func TestRightNavigationHandler_Match(t *testing.T) {
+	h := handlers.NewRightNavigationHandler()
+
+	tests := []struct {
+		name     string
+		mode     state.Mode
+		key      string
+		expected bool
+	}{
+		{
+			name:     "Matches 'right' in Navigation Mode",
+			mode:     state.NavigationMode,
+			key:      "right",
+			expected: true,
+		},
+		{
+			name:     "Matches 'l' in Navigation Mode",
+			mode:     state.NavigationMode,
+			key:      "l",
+			expected: true,
+		},
+		{
+			name:     "Ignores 'right' in Input Mode",
+			mode:     state.InputMode,
+			key:      "right",
+			expected: false,
+		},
+		{
+			name:     "Ignores 'l' in Input Mode",
+			mode:     state.InputMode,
+			key:      "l",
+			expected: false,
+		},
+		{
+			name:     "Ignores other keys in Navigation Mode",
+			mode:     state.NavigationMode,
+			key:      "left",
+			expected: false,
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			s := state.New(state.WithMode(tt.mode))
+			msg := tea.KeyMsg{Type: tea.KeyRunes, Runes: []rune(tt.key)}
+
+			if tt.key == "right" {
+				msg = tea.KeyMsg{Type: tea.KeyRight}
+			}
+
+			if got := h.Match(s, msg); got != tt.expected {
+				t.Errorf("Match() = %v, want %v", got, tt.expected)
+			}
+		})
+	}
+}
+
+func TestRightNavigationHandler_Handle(t *testing.T) {
+	h := handlers.NewRightNavigationHandler()
+
+	tiers := make([]core.Tier, 6)
+	tiers[0] = core.Tier{Name: "S", Items: []core.Item{"A", "B"}}
+
+	s := state.New(
+		state.WithTiers(tiers),
+		state.WithCursor(0, 0),
+		state.WithMode(state.NavigationMode),
+	)
+
+	msg := tea.KeyMsg{Type: tea.KeyRight}
+	cmd := h.Handle(s, msg)
+
+	if s.CursorCol() != 1 {
+		t.Errorf("Expected cursor to move to Col 1, got %d", s.CursorCol())
+	}
+
+	if cmd != nil {
+		t.Error("Expected Handle to return nil, got a command")
+	}
+}