Initial Commit

helpers/text_helpers.go

@@ -0,0 +1,159 @@
+/*
+Copyright © Brian Buller <brian@bullercodeworks.com>
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.
+*/
+package helpers
+
+import (
+	"bytes"
+	"fmt"
+	"strings"
+	"unicode"
+)
+
+type Align int
+
+const (
+	AlignLeft = iota
+	AlignCenter
+	AlignRight
+)
+
+func Center(txt string, width int) string {
+	if len(txt) >= width {
+		// Trim from beg & end until width
+		for len(txt) > width {
+			txt = txt[:len(txt)-1]
+			if len(txt) > width {
+				txt = txt[1:]
+			}
+		}
+		return txt
+	}
+	for len(txt) < width {
+		txt = fmt.Sprintf(" %s", txt)
+		if len(txt) < width {
+			txt = fmt.Sprintf("%s ", txt)
+		}
+	}
+	return txt
+}
+
+func CenterBetween(txt, left, right string, width int) string {
+	if len(txt) >= width {
+		return Center(txt, width)
+	}
+	for len(txt) < width {
+		txt = fmt.Sprintf("%s%s", left, txt)
+		if len(txt) < width {
+			txt = fmt.Sprintf("%s%s", txt, right)
+		}
+	}
+	return txt
+}
+
+func PadR(txt string, width int) string {
+	if len(txt) < width {
+		txt = fmt.Sprintf("%s%s", txt, strings.Repeat(" ", width-len(txt)))
+	}
+	return txt
+}
+
+func PadL(txt string, width int) string {
+	if len(txt) < width {
+		txt = fmt.Sprintf("%s%s", strings.Repeat(" ", width-len(txt)), txt)
+	}
+	return txt
+}
+
+// WrapText inserts new lines to make the text
+// wrap at width 'w'
+func WrapText(txt string, w int) string {
+	init := make([]byte, 0, len(txt))
+	buf := bytes.NewBuffer(init)
+	var current uint
+	var wordBuf, spaceBuf bytes.Buffer
+	var wordBufLen, spaceBufLen uint
+	writeBufs := func() {
+		current += spaceBufLen + wordBufLen
+		spaceBuf.WriteTo(buf)
+		spaceBuf.Reset()
+		spaceBufLen = 0
+		wordBuf.WriteTo(buf)
+		wordBuf.Reset()
+		wordBufLen = 0
+	}
+	for _, char := range txt {
+		if char == '\n' {
+			// _Must_ wrap at newline
+			if wordBuf.Len() == 0 {
+				if int(current+spaceBufLen) > w {
+					current = 0
+				} else {
+					current += spaceBufLen
+					spaceBuf.WriteTo(buf)
+				}
+				spaceBuf.Reset()
+				spaceBufLen = 0
+			} else {
+				writeBufs()
+			}
+			buf.WriteRune(char)
+			current = 0
+		} else if unicode.IsSpace(char) && char != 0xA0 {
+			// Can wrap at whitespace
+			if spaceBuf.Len() == 0 || wordBuf.Len() > 0 {
+				writeBufs()
+			}
+			spaceBuf.WriteRune(char)
+			spaceBufLen++
+		} else {
+			wordBuf.WriteRune(char)
+			wordBufLen++
+			if int(current+wordBufLen+spaceBufLen) > w && int(wordBufLen) < w {
+				buf.WriteRune('\n')
+				current = 0
+				spaceBuf.Reset()
+				spaceBufLen = 0
+			}
+		}
+	}
+
+	if wordBuf.Len() == 0 {
+		if int(current+spaceBufLen) <= w {
+			spaceBuf.WriteTo(buf)
+		}
+	} else {
+		spaceBuf.WriteTo(buf)
+		wordBuf.WriteTo(buf)
+	}
+	return buf.String()
+}
+
+func Longest(of []string) int {
+	var ret int
+	for i := range of {
+		tst := len(of[i])
+		if tst > ret {
+			ret = tst
+		}
+	}
+	return ret
+}