| 1 | package logreader |
| 2 | |
| 3 | import ( |
| 4 | "regexp" |
| 5 | "strings" |
| 6 | |
| 7 | "github.com/charmbracelet/x/ansi" |
| 8 | ) |
| 9 | |
| 10 | var sgrRe = regexp.MustCompile(`\x1b\[[0-9;]*m`) |
| 11 | |
| 12 | const resetSeq = "\x1b[0m" |
| 13 | |
| 14 | // ansiWrap hard-wraps s at maxW display columns (ANSI-aware), then ensures |
| 15 | // each output line carries its own SGR state so that the viewport can render |
| 16 | // any line independently without relying on prior lines' escape codes. |
| 17 | func ansiWrap(s string, maxW int) string { |
| 18 | if maxW <= 0 { |
| 19 | return s |
| 20 | } |
| 21 | wrapped := ansi.Hardwrap(s, maxW, true) |
| 22 | lines := strings.Split(wrapped, "\n") |
| 23 | |
| 24 | var lastSGR string |
| 25 | var b strings.Builder |
| 26 | b.Grow(len(wrapped) + len(lines)*20) |
| 27 | |
| 28 | for i, line := range lines { |
| 29 | if i > 0 { |
| 30 | b.WriteByte('\n') |
| 31 | } |
| 32 | |
| 33 | // If this line doesn't start with an SGR and we have one pending, |
| 34 | // re-emit it so the line is self-contained. |
| 35 | if lastSGR != "" && lastSGR != resetSeq && !strings.HasPrefix(line, "\x1b[") { |
| 36 | b.WriteString(lastSGR) |
| 37 | } |
| 38 | b.WriteString(line) |
| 39 | |
| 40 | // Track all SGR sequences in this line; keep the last one. |
| 41 | if matches := sgrRe.FindAllString(line, -1); len(matches) > 0 { |
| 42 | lastSGR = matches[len(matches)-1] |
| 43 | } |
| 44 | } |
| 45 | |
| 46 | return b.String() |
| 47 | } |
| 48 | |