Split up tui code into packages (views/*, shared, util)

pkg/tui/util/util.go

@@ -0,0 +1,104 @@
+package util
+
+import (
+	"fmt"
+	"os"
+	"os/exec"
+	"strings"
+
+	"github.com/charmbracelet/bubbles/viewport"
+	tea "github.com/charmbracelet/bubbletea"
+	"github.com/charmbracelet/lipgloss"
+	"github.com/muesli/reflow/ansi"
+)
+
+type MsgTempfileEditorClosed string
+
+// OpenTempfileEditor opens an $EDITOR on a new temporary file with the given
+// content. Upon closing, the contents of the file are read back returned
+// wrapped in a msgTempfileEditorClosed returned by the tea.Cmd
+func OpenTempfileEditor(pattern string, content string, placeholder string) tea.Cmd {
+	msgFile, _ := os.CreateTemp("/tmp", pattern)
+
+	err := os.WriteFile(msgFile.Name(), []byte(placeholder+content), os.ModeAppend)
+	if err != nil {
+		return func() tea.Msg { return err }
+	}
+
+	editor := os.Getenv("EDITOR")
+	if editor == "" {
+		editor = "vim"
+	}
+
+	c := exec.Command(editor, msgFile.Name())
+	return tea.ExecProcess(c, func(err error) tea.Msg {
+		bytes, err := os.ReadFile(msgFile.Name())
+		if err != nil {
+			return err
+		}
+		os.Remove(msgFile.Name())
+		fileContents := string(bytes)
+		if strings.HasPrefix(fileContents, placeholder) {
+			fileContents = fileContents[len(placeholder):]
+		}
+		stripped := strings.Trim(fileContents, "\n \t")
+		return MsgTempfileEditorClosed(stripped)
+	})
+}
+
+// similar to lipgloss.Height, except returns 0 on empty strings
+func Height(str string) int {
+	if str == "" {
+		return 0
+	}
+	return strings.Count(str, "\n") + 1
+}
+
+// truncate a string until its rendered cell width + the provided tail fits
+// within the given width
+func TruncateToCellWidth(str string, width int, tail string) string {
+	cellWidth := ansi.PrintableRuneWidth(str)
+	if cellWidth <= width {
+		return str
+	}
+	tailWidth := ansi.PrintableRuneWidth(tail)
+	for {
+		str = str[:len(str)-((cellWidth+tailWidth)-width)]
+		cellWidth = ansi.PrintableRuneWidth(str)
+		if cellWidth+tailWidth <= max(width, 0) {
+			break
+		}
+	}
+	return str + tail
+}
+
+// fraction is the fraction of the total screen height into view the offset
+// should be scrolled into view. 0.5 = items will be snapped to middle of
+// view
+func ScrollIntoView(vp *viewport.Model, offset int, edge int) {
+	currentOffset := vp.YOffset
+	if offset >= currentOffset && offset < currentOffset+vp.Height {
+		return
+	}
+	distance := currentOffset - offset
+	if distance < 0 {
+		// we should scroll down until it just comes into view
+		vp.SetYOffset(currentOffset - (distance + (vp.Height - edge)) + 1)
+	} else {
+		// we should scroll up
+		vp.SetYOffset(currentOffset - distance - edge)
+	}
+}
+
+func ErrorBanner(err error, width int) string {
+	if err == nil {
+		return ""
+	}
+	return lipgloss.NewStyle().
+		Width(width).
+		AlignHorizontal(lipgloss.Center).
+		Bold(true).
+		Foreground(lipgloss.Color("1")).
+		Render(fmt.Sprintf("%s", err))
+}
+