❤️ 完整开源界面和内核 https://github.com/siyuan-note/siyuan/issues/5013

kernel/search/mark.go

@@ -0,0 +1,122 @@
+// SiYuan - Build Your Eternal Digital Garden
+// Copyright (c) 2020-present, b3log.org
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Affero General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU Affero General Public License for more details.
+//
+// You should have received a copy of the GNU Affero General Public License
+// along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+package search
+
+import (
+	"regexp"
+	"strings"
+	"unicode/utf8"
+
+	"github.com/88250/lute/html"
+)
+
+func MarkText(text string, keyword string, beforeLen int, caseSensitive bool) (pos int, marked string) {
+	if "" == keyword {
+		return -1, text
+	}
+	text = html.EscapeString(text)
+	keywords := SplitKeyword(keyword)
+	marked = EncloseHighlighting(text, keywords, "<mark>", "</mark>", caseSensitive)
+
+	pos = strings.Index(marked, "<mark>")
+	if 0 > pos {
+		return
+	}
+
+	var before []rune
+	var count int
+	for i := pos; 0 < i; { // 关键字前面太长的话缩短一些
+		r, size := utf8.DecodeLastRuneInString(marked[:i])
+		i -= size
+		before = append([]rune{r}, before...)
+		count++
+		if beforeLen < count {
+			before = append([]rune("..."), before...)
+			break
+		}
+	}
+	marked = string(before) + marked[pos:]
+	return
+}
+
+const TermSep = "__term@sep__"
+
+func SplitKeyword(keyword string) (keywords []string) {
+	keyword = strings.TrimSpace(keyword)
+	if "" == keyword {
+		return
+	}
+	words := strings.Split(keyword, TermSep)
+	if 1 < len(words) {
+		for _, word := range words {
+			if "" == word {
+				continue
+			}
+			keywords = append(keywords, word)
+		}
+	} else {
+		keywords = append(keywords, keyword)
+	}
+	return
+}
+
+func EncloseHighlighting(text string, keywords []string, openMark, closeMark string, caseSensitive bool) string {
+	ic := "(?i)"
+	if caseSensitive {
+		ic = "(?)"
+	}
+	re := ic + "("
+	for i, k := range keywords {
+		k = keyword2regexp(k)
+		re += "(" + k + ")"
+		if i < len(keywords)-1 {
+			re += "|"
+		}
+	}
+	re += ")"
+	if reg, err := regexp.Compile(re); nil == err {
+		text = reg.ReplaceAllStringFunc(text, func(s string) string {
+			return openMark + s + closeMark
+		})
+	} else {
+		for _, k := range keywords {
+			k = keyword2regexp(k)
+			var repls, words []string
+			if re, err := regexp.Compile(ic + k); nil == err {
+				words = re.FindAllString(text, -1)
+			} else {
+				re, _ := regexp.Compile(ic + regexp.QuoteMeta(k))
+				words = re.FindAllString(text, -1)
+			}
+			for _, word := range words {
+				repls = append(repls, word, openMark+word+closeMark)
+			}
+			replacer := strings.NewReplacer(repls...)
+			text = replacer.Replace(text)
+		}
+	}
+	return text
+}
+
+func keyword2regexp(k string) string {
+	k = strings.ReplaceAll(k, "*", ".*")
+	k = strings.ReplaceAll(k, "?", ".")
+	k = strings.ReplaceAll(k, "%", ".*")
+	k = strings.ReplaceAll(k, "_", ".")
+	k = strings.ReplaceAll(k, "\\\\", "\\")
+	return k
+}