88 lines
3.4 KiB
Kotlin

/*
* Copyright 2025 Sergey S. Chernov real.sergeych@gmail.com
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
*/
/*
* Site-like wrapper for Lyng highlighter that renders HTML spans with CSS classes
* compatible with the site styles. Kept in package net.sergeych.site for backwards
* compatibility with existing code and tests.
*/
package net.sergeych.site
import net.sergeych.lyng.highlight.HighlightKind
import net.sergeych.lyng.highlight.SimpleLyngHighlighter
import net.sergeych.lyngweb.htmlEscape
/**
* Minimal HTML renderer for Lyng syntax highlighting, compatible with the site CSS.
*
* This object is kept in the legacy package `net.sergeych.site` to preserve
* backward compatibility with existing imports and tests in dependent modules.
* It renders spans with the `hl-*` classes used by the site (e.g., `hl-kw`,
* `hl-id`, `hl-num`).
*/
object SiteHighlight {
private fun cssClassForKind(kind: HighlightKind): String = when (kind) {
HighlightKind.Keyword -> "hl-kw"
HighlightKind.TypeName -> "hl-ty"
HighlightKind.Identifier -> "hl-id"
HighlightKind.Number -> "hl-num"
HighlightKind.String -> "hl-str"
HighlightKind.Char -> "hl-ch"
HighlightKind.Regex -> "hl-rx"
HighlightKind.Comment -> "hl-cmt"
HighlightKind.Operator -> "hl-op"
HighlightKind.Punctuation -> "hl-punc"
HighlightKind.Label -> "hl-lbl"
HighlightKind.Directive -> "hl-dir"
HighlightKind.Error -> "hl-err"
}
/**
* Converts plain Lyng source [text] into HTML with `<span>` wrappers using
* site-compatible `hl-*` classes.
*
* Non-highlighted parts are HTML-escaped. If the highlighter returns no
* tokens, the entire string is returned as an escaped plain text.
*
* Example:
* ```kotlin
* val html = SiteHighlight.renderHtml("assertEquals(1, 1)")
* // => "<span class=\"hl-id\">assertEquals</span><span class=\"hl-punc\">(</span>..."
* ```
*
* @param text Lyng code to render (plain text).
* @return HTML string with `hl-*` styled tokens.
*/
fun renderHtml(text: String): String {
val highlighter = SimpleLyngHighlighter()
val spans = highlighter.highlight(text)
if (spans.isEmpty()) return htmlEscape(text)
val sb = StringBuilder(text.length + spans.size * 16)
var pos = 0
for (s in spans) {
if (s.range.start > pos) sb.append(htmlEscape(text.substring(pos, s.range.start)))
val cls = cssClassForKind(s.kind)
sb.append('<').append("span class=\"").append(cls).append('\"').append('>')
sb.append(htmlEscape(text.substring(s.range.start, s.range.endExclusive)))
sb.append("</span>")
pos = s.range.endExclusive
}
if (pos < text.length) sb.append(htmlEscape(text.substring(pos)))
return sb.toString()
}
}