v0.1.0 initial commit

tui/form.go

@@ -0,0 +1,228 @@
+package tui
+
+import "github.com/lixenwraith/terminal"
+
+// FormField pairs a label with an editable text field
+type FormField struct {
+	Label string
+	State *TextFieldState
+}
+
+// FormState holds state for a multi-field form with focus tracking
+type FormState struct {
+	Fields []FormField
+	Focus  int
+}
+
+// NewFormState creates a form with labeled fields initialized to empty values
+func NewFormState(labels ...string) *FormState {
+	fields := make([]FormField, len(labels))
+	for i, label := range labels {
+		fields[i] = FormField{
+			Label: label,
+			State: NewTextFieldState(""),
+		}
+	}
+	return &FormState{Fields: fields}
+}
+
+// Value returns the text value of the field at idx
+func (f *FormState) Value(idx int) string {
+	if idx >= 0 && idx < len(f.Fields) {
+		return f.Fields[idx].State.Value()
+	}
+	return ""
+}
+
+// SetValue replaces the text of the field at idx
+func (f *FormState) SetValue(idx int, val string) {
+	if idx >= 0 && idx < len(f.Fields) {
+		f.Fields[idx].State.SetValue(val)
+	}
+}
+
+// Clear empties all fields in the form
+func (f *FormState) Clear() {
+	for i := range f.Fields {
+		f.Fields[i].State.Clear()
+	}
+}
+
+// FocusNext moves focus to the next field, wrapping around
+func (f *FormState) FocusNext() {
+	if len(f.Fields) > 0 {
+		f.Focus = (f.Focus + 1) % len(f.Fields)
+	}
+}
+
+// FocusPrev moves focus to the previous field, wrapping around
+func (f *FormState) FocusPrev() {
+	if len(f.Fields) > 0 {
+		f.Focus = (f.Focus - 1 + len(f.Fields)) % len(f.Fields)
+	}
+}
+
+// CurrentField returns the TextFieldState of the focused field, or nil
+func (f *FormState) CurrentField() *TextFieldState {
+	if f.Focus >= 0 && f.Focus < len(f.Fields) {
+		return f.Fields[f.Focus].State
+	}
+	return nil
+}
+
+// HandleKey processes keyboard input for form navigation and field editing, returns true if state changed
+func (f *FormState) HandleKey(key terminal.Key, r rune, mod terminal.Modifier) bool {
+	switch key {
+	case terminal.KeyTab:
+		if mod&terminal.ModShift != 0 {
+			f.FocusPrev()
+		} else {
+			f.FocusNext()
+		}
+		return true
+	case terminal.KeyUp:
+		f.FocusPrev()
+		return true
+	case terminal.KeyDown:
+		f.FocusNext()
+		return true
+	default:
+		if field := f.CurrentField(); field != nil {
+			return field.HandleKey(key, r, mod)
+		}
+	}
+	return false
+}
+
+// FormOpts configures form rendering
+type FormOpts struct {
+	LabelWidth int
+	Spacing    int
+	Style      FormStyle
+}
+
+// FormStyle defines form colors
+type FormStyle struct {
+	LabelFg  terminal.RGB
+	FieldFg  terminal.RGB
+	FieldBg  terminal.RGB
+	FocusBg  terminal.RGB
+	CursorFg terminal.RGB
+	CursorBg terminal.RGB
+	Bg       terminal.RGB
+}
+
+// DefaultFormStyle returns default form colors
+func DefaultFormStyle() FormStyle {
+	return FormStyle{
+		LabelFg:  terminal.RGB{R: 150, G: 150, B: 180},
+		FieldFg:  terminal.RGB{R: 220, G: 220, B: 220},
+		FieldBg:  terminal.RGB{R: 35, G: 35, B: 45},
+		FocusBg:  terminal.RGB{R: 45, G: 45, B: 60},
+		CursorFg: terminal.RGB{R: 0, G: 0, B: 0},
+		CursorBg: terminal.RGB{R: 200, G: 200, B: 200},
+		Bg:       terminal.RGB{R: 25, G: 25, B: 35},
+	}
+}
+
+// Form renders a multi-field form with labels and editable text fields, returns height used
+func (r Region) Form(state *FormState, opts FormOpts) int {
+	if len(state.Fields) == 0 || r.H < 1 {
+		return 0
+	}
+
+	style := opts.Style
+	if style == (FormStyle{}) {
+		style = DefaultFormStyle()
+	}
+
+	labelW := opts.LabelWidth
+	if labelW <= 0 {
+		for _, f := range state.Fields {
+			if w := RuneLen(f.Label); w > labelW {
+				labelW = w
+			}
+		}
+		labelW += 2
+	}
+
+	spacing := opts.Spacing
+	if spacing < 1 {
+		spacing = 1
+	}
+
+	y := 0
+	for i, field := range state.Fields {
+		if y >= r.H {
+			break
+		}
+
+		isFocused := i == state.Focus
+
+		// Label
+		label := field.Label + ":"
+		for j, ch := range label {
+			if j >= labelW || j >= r.W {
+				break
+			}
+			r.Cell(j, y, ch, style.LabelFg, style.Bg, terminal.AttrNone)
+		}
+
+		// Field area
+		fieldX := labelW
+		fieldW := r.W - labelW
+		if fieldW < 1 {
+			y += spacing
+			continue
+		}
+
+		fieldBg := style.FieldBg
+		if isFocused {
+			fieldBg = style.FocusBg
+		}
+
+		for x := fieldX; x < fieldX+fieldW && x < r.W; x++ {
+			r.Cell(x, y, ' ', style.FieldFg, fieldBg, terminal.AttrNone)
+		}
+
+		// Render text using existing TextField logic
+		text := field.State.Text
+		scroll := field.State.Scroll
+		cursor := field.State.Cursor
+
+		field.State.AdjustScroll(fieldW)
+		scroll = field.State.Scroll
+
+		for x := 0; x < fieldW; x++ {
+			runeIdx := scroll + x
+			ch := ' '
+			if runeIdx < len(text) {
+				ch = text[runeIdx]
+			}
+
+			fg := style.FieldFg
+			bg := fieldBg
+
+			if isFocused && runeIdx == cursor {
+				fg = style.CursorFg
+				bg = style.CursorBg
+			}
+
+			if fieldX+x < r.W {
+				r.Cell(fieldX+x, y, ch, fg, bg, terminal.AttrNone)
+			}
+		}
+
+		// Cursor at end of text
+		if isFocused && cursor == len(text) {
+			cursorX := fieldX + cursor - scroll
+			if cursorX >= fieldX && cursorX < fieldX+fieldW && cursorX < r.W {
+				r.Cell(cursorX, y, ' ', style.CursorFg, style.CursorBg, terminal.AttrNone)
+			}
+		}
+
+		y += spacing
+	}
+
+	return y
+}