Fix high prio recommendations, add error / health screen

text_editor.go

@@ -3,10 +3,12 @@ package main
 import (
 	"strings"
 	"unicode"
+	"unicode/utf8"
 
 	tea "github.com/charmbracelet/bubbletea"
 	"github.com/charmbracelet/lipgloss"
 	"github.com/charmbracelet/x/ansi"
+	"github.com/rivo/uniseg"
 )
 
 type textEditorMode string
@@ -69,7 +71,7 @@ func (e *textEditor) handleKeyAtWidth(key tea.KeyMsg, multiline bool, wrapWidth
 			e.clearPending()
 			start, _ := editorLineBounds(e.Text, e.Cursor, wrapWidth)
 			if e.Cursor > start {
-				e.Cursor--
+				e.Cursor = max(start, previousGraphemeBoundary(e.Text, e.Cursor))
 			}
 			return true
 		}
@@ -92,10 +94,10 @@ func (e *textEditor) handleStandardKey(key tea.KeyMsg, multiline bool, wrapWidth
 	switch {
 	case key.Type != tea.KeyRunes && key.Type != tea.KeySpace &&
 		keyMatches(k, e.keys.Navigation.Left):
-		e.Cursor = max(0, e.Cursor-1)
+		e.Cursor = previousGraphemeBoundary(e.Text, e.Cursor)
 	case key.Type != tea.KeyRunes && key.Type != tea.KeySpace &&
 		keyMatches(k, e.keys.Navigation.Right):
-		e.Cursor = min(len([]rune(e.Text)), e.Cursor+1)
+		e.Cursor = nextGraphemeBoundary(e.Text, e.Cursor)
 	case key.Type != tea.KeyRunes && key.Type != tea.KeySpace &&
 		keyMatches(k, e.keys.Navigation.Up):
 		if !multiline {
@@ -130,6 +132,7 @@ func (e *textEditor) handleStandardKey(key tea.KeyMsg, multiline bool, wrapWidth
 			return false
 		}
 	}
+	e.Cursor = previousOrCurrentGraphemeBoundary(e.Text, e.Cursor)
 	return true
 }
 
@@ -166,7 +169,7 @@ func (e *textEditor) handleNormalKey(key tea.KeyMsg, multiline bool, wrapWidth i
 		e.Mode = textEditorInsert
 	case keyMatches(k, e.keys.Vim.Append):
 		_, end := editorLineBounds(e.Text, e.Cursor, wrapWidth)
-		e.Cursor = min(end, e.Cursor+1)
+		e.Cursor = min(end, nextGraphemeBoundary(e.Text, e.Cursor))
 		e.Mode = textEditorInsert
 	case keyMatches(k, e.keys.Vim.InsertLineStart):
 		e.Cursor = firstNonBlankAtWidth(e.Text, e.Cursor, wrapWidth)
@@ -192,9 +195,12 @@ func (e *textEditor) handleNormalKey(key tea.KeyMsg, multiline bool, wrapWidth i
 		e.Mode = textEditorInsert
 	case keyMatches(k, e.keys.Navigation.Left):
 		start, _ := editorLineBounds(e.Text, e.Cursor, wrapWidth)
-		e.Cursor = max(start, e.Cursor-1)
+		e.Cursor = max(start, previousGraphemeBoundary(e.Text, e.Cursor))
 	case keyMatches(k, e.keys.Navigation.Right):
-		e.Cursor = min(normalEditorLineLast(e.Text, e.Cursor, wrapWidth), e.Cursor+1)
+		e.Cursor = min(
+			normalEditorLineLast(e.Text, e.Cursor, wrapWidth),
+			nextGraphemeBoundary(e.Text, e.Cursor),
+		)
 	case keyMatches(k, e.keys.Navigation.Down):
 		if multiline {
 			e.Cursor = moveEditorCursorLine(e.Text, e.Cursor, 1, wrapWidth, true)
@@ -266,6 +272,7 @@ func (e *textEditor) handleNormalKey(key tea.KeyMsg, multiline bool, wrapWidth i
 	default:
 		return false
 	}
+	e.Cursor = previousOrCurrentGraphemeBoundary(e.Text, e.Cursor)
 	return true
 }
 
@@ -347,7 +354,9 @@ func (e textEditor) selectionBounds(wrapWidth int) (int, int, bool) {
 	anchor := clamp(e.visualAnchor, 0, len(runes))
 	cursor := clamp(e.Cursor, 0, len(runes))
 	if !e.visualLine {
-		start, end := min(anchor, cursor), min(len(runes), max(anchor, cursor)+1)
+		start := previousOrCurrentGraphemeBoundary(e.Text, min(anchor, cursor))
+		end := nextGraphemeBoundary(e.Text, max(anchor, cursor))
+		end = min(len(runes), end)
 		return start, end, end > start
 	}
 	anchorStart, anchorEnd := editorLineBounds(e.Text, anchor, wrapWidth)
@@ -386,7 +395,7 @@ func (e *textEditor) deleteSelection(wrapWidth int) {
 	e.Text = string(append(runes[:start], runes[end:]...))
 	e.Cursor = min(start, len([]rune(e.Text)))
 	if e.Cursor == len([]rune(e.Text)) && e.Cursor > 0 {
-		e.Cursor--
+		e.Cursor = previousGraphemeBoundary(e.Text, e.Cursor)
 	}
 	e.stopVisual()
 }
@@ -411,11 +420,11 @@ func (e *textEditor) pasteClipboard(replaceSelection bool, wrapWidth int) {
 		e.stopVisual()
 	} else {
 		_, end := editorLineBounds(e.Text, e.Cursor, 0)
-		e.Cursor = min(end, e.Cursor+1)
+		e.Cursor = min(end, nextGraphemeBoundary(e.Text, e.Cursor))
 	}
 	e.insert(value)
 	if e.Cursor > 0 {
-		e.Cursor--
+		e.Cursor = previousGraphemeBoundary(e.Text, e.Cursor)
 	}
 }
 
@@ -442,8 +451,9 @@ func (e *textEditor) deleteBefore() {
 	if e.Cursor == 0 {
 		return
 	}
-	value = append(value[:e.Cursor-1], value[e.Cursor:]...)
-	e.Cursor--
+	start := previousGraphemeBoundary(e.Text, e.Cursor)
+	value = append(value[:start], value[e.Cursor:]...)
+	e.Cursor = start
 	e.Text = string(value)
 }
 
@@ -453,10 +463,56 @@ func (e *textEditor) deleteAt() {
 	if e.Cursor == len(value) {
 		return
 	}
-	value = append(value[:e.Cursor], value[e.Cursor+1:]...)
+	end := nextGraphemeBoundary(e.Text, e.Cursor)
+	value = append(value[:e.Cursor], value[end:]...)
 	e.Text = string(value)
 }
 
+func graphemeBoundaries(value string) []int {
+	boundaries := []int{0}
+	graphemes := uniseg.NewGraphemes(value)
+	offset := 0
+	for graphemes.Next() {
+		offset += utf8.RuneCountInString(graphemes.Str())
+		boundaries = append(boundaries, offset)
+	}
+	return boundaries
+}
+
+func previousGraphemeBoundary(value string, cursor int) int {
+	cursor = clamp(cursor, 0, len([]rune(value)))
+	previous := 0
+	for _, boundary := range graphemeBoundaries(value) {
+		if boundary >= cursor {
+			return previous
+		}
+		previous = boundary
+	}
+	return previous
+}
+
+func previousOrCurrentGraphemeBoundary(value string, cursor int) int {
+	cursor = clamp(cursor, 0, len([]rune(value)))
+	previous := 0
+	for _, boundary := range graphemeBoundaries(value) {
+		if boundary > cursor {
+			return previous
+		}
+		previous = boundary
+	}
+	return previous
+}
+
+func nextGraphemeBoundary(value string, cursor int) int {
+	cursor = clamp(cursor, 0, len([]rune(value)))
+	for _, boundary := range graphemeBoundaries(value) {
+		if boundary > cursor {
+			return boundary
+		}
+	}
+	return len([]rune(value))
+}
+
 func (e *textEditor) performFind(command, target rune, remember bool, wrapWidth int) {
 	runes := []rune(e.Text)
 	cursor := clamp(e.Cursor, 0, len(runes))