Refactor syntax highlighting infrastructure and related classes.

- Moved all language highlighter implementations (`CppHighlighter`, `GoHighlighter`, `JsonHighlighter`, etc.), the engine, and registry to `syntax/`.
2025-12-02 01:36:26 -08:00
parent ceef6af3ae
commit d15b241140
64 changed files with 3957 additions and 2582 deletions
--- a/syntax/MarkdownHighlighter.cc
+++ b/syntax/MarkdownHighlighter.cc
@@ -0,0 +1,132 @@
+#include "MarkdownHighlighter.h"
+#include "../Buffer.h"
+#include <cctype>
+
+namespace kte {
+static void
+push_span(std::vector<HighlightSpan> &out, int a, int b, TokenKind k)
+{
+	if (b > a)
+		out.push_back({a, b, k});
+}
+
+
+void
+MarkdownHighlighter::HighlightLine(const Buffer &buf, int row, std::vector<HighlightSpan> &out) const
+{
+	LineState st; // not used in stateless entry
+	(void) HighlightLineStateful(buf, row, st, out);
+}
+
+
+StatefulHighlighter::LineState
+MarkdownHighlighter::HighlightLineStateful(const Buffer &buf, int row, const LineState &prev,
+                                           std::vector<HighlightSpan> &out) const
+{
+	StatefulHighlighter::LineState state = prev;
+	const auto &rows                     = buf.Rows();
+	if (row < 0 || static_cast<std::size_t>(row) >= rows.size())
+		return state;
+	std::string s = static_cast<std::string>(rows[static_cast<std::size_t>(row)]);
+	int n         = static_cast<int>(s.size());
+
+	// Reuse in_block_comment flag as "in fenced code" state.
+	if (state.in_block_comment) {
+		// If line contains closing fence ``` then close after it
+		auto pos = s.find("```");
+		if (pos == std::string::npos) {
+			push_span(out, 0, n, TokenKind::String);
+			state.in_block_comment = true;
+			return state;
+		} else {
+			int end = static_cast<int>(pos + 3);
+			push_span(out, 0, end, TokenKind::String);
+			// rest of line processed normally after fence
+			int i = end;
+			// whitespace
+			if (i < n)
+				push_span(out, i, n, TokenKind::Default);
+			state.in_block_comment = false;
+			return state;
+		}
+	}
+
+	// Detect fenced code block start at beginning (allow leading spaces)
+	int bol = 0;
+	while (bol < n && (s[bol] == ' ' || s[bol] == '\t'))
+		++bol;
+	if (bol + 3 <= n && s.compare(bol, 3, "```") == 0) {
+		push_span(out, bol, n, TokenKind::String);
+		state.in_block_comment = true; // enter fenced mode
+		return state;
+	}
+
+	// Headings: lines starting with 1-6 '#'
+	if (bol < n && s[bol] == '#') {
+		int j = bol;
+		while (j < n && s[j] == '#')
+			++j; // hashes
+		// include following space and text as Keyword to stand out
+		push_span(out, bol, n, TokenKind::Keyword);
+		return state;
+	}
+
+	// Process inline: emphasis and code spans
+	int i = 0;
+	while (i < n) {
+		char c = s[i];
+		if (c == '`') {
+			int j = i + 1;
+			while (j < n && s[j] != '`')
+				++j;
+			if (j < n)
+				++j;
+			push_span(out, i, j, TokenKind::String);
+			i = j;
+			continue;
+		}
+		if (c == '*' || c == '_') {
+			// bold/italic markers: treat the marker and until next same marker as Type to highlight
+			char m = c;
+			int j  = i + 1;
+			while (j < n && s[j] != m)
+				++j;
+			if (j < n)
+				++j;
+			push_span(out, i, j, TokenKind::Type);
+			i = j;
+			continue;
+		}
+		// links []() minimal: treat [text](url) as Function
+		if (c == '[') {
+			int j = i + 1;
+			while (j < n && s[j] != ']')
+				++j;
+			if (j < n)
+				++j; // include ]
+			if (j < n && s[j] == '(') {
+				while (j < n && s[j] != ')')
+					++j;
+				if (j < n)
+					++j;
+			}
+			push_span(out, i, j, TokenKind::Function);
+			i = j;
+			continue;
+		}
+		// whitespace
+		if (c == ' ' || c == '\t') {
+			int j = i + 1;
+			while (j < n && (s[j] == ' ' || s[j] == '\t'))
+				++j;
+			push_span(out, i, j, TokenKind::Whitespace);
+			i = j;
+			continue;
+		}
+		// fallback: default single char
+		push_span(out, i, i + 1, TokenKind::Default);
+		++i;
+	}
+	return state;
+}
+} // namespace kte