Add syntax highlighting infrastructure

- Introduced `HighlighterRegistry` with support for multiple language highlighters (e.g., JSON, Markdown, Python). - Added `JsonHighlighter` implementation for basic JSON syntax highlighting.
2025-12-01 18:20:36 -08:00
parent 4d84b352eb
commit 1a77f28ce4
38 changed files with 1701 additions and 590 deletions
--- a/PythonHighlighter.cc
+++ b/PythonHighlighter.cc
@@ -0,0 +1,85 @@
+#include "PythonHighlighter.h"
+#include "Buffer.h"
+#include <cctype>
+
+namespace kte {
+
+static void push(std::vector<HighlightSpan> &out, int a, int b, TokenKind k){ if (b>a) out.push_back({a,b,k}); }
+static bool is_ident_start(char c){ return std::isalpha(static_cast<unsigned char>(c)) || c=='_'; }
+static bool is_ident_char(char c){ return std::isalnum(static_cast<unsigned char>(c)) || c=='_'; }
+
+PythonHighlighter::PythonHighlighter()
+{
+    const char* kw[] = {"and","as","assert","break","class","continue","def","del","elif","else","except","False","finally","for","from","global","if","import","in","is","lambda","None","nonlocal","not","or","pass","raise","return","True","try","while","with","yield"};
+    for (auto s: kw) kws_.insert(s);
+}
+
+void PythonHighlighter::HighlightLine(const Buffer &buf, int row, std::vector<HighlightSpan> &out) const
+{
+    LineState st; (void)HighlightLineStateful(buf, row, st, out);
+}
+
+StatefulHighlighter::LineState PythonHighlighter::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());
+
+    // Triple-quoted string continuation uses in_raw_string with raw_delim either "'''" or "\"\"\""
+    if (state.in_raw_string && (state.raw_delim == "'''" || state.raw_delim == "\"\"\"")) {
+        auto pos = s.find(state.raw_delim);
+        if (pos == std::string::npos) {
+            push(out, 0, n, TokenKind::String);
+            return state; // still inside
+        } else {
+            int end = static_cast<int>(pos + static_cast<int>(state.raw_delim.size()));
+            push(out, 0, end, TokenKind::String);
+            // remainder processed normally
+            s = s.substr(end);
+            n = static_cast<int>(s.size());
+            state.in_raw_string = false; state.raw_delim.clear();
+            // Continue parsing remainder as a separate small loop
+            int base = end; // original offset, but we already emitted to 'out' with base=0; following spans should be from 'end'
+            // For simplicity, mark rest as Default
+            if (n>0) push(out, base, base + n, TokenKind::Default);
+            return state;
+        }
+    }
+
+    int i = 0;
+    // Detect comment start '#', ignoring inside strings
+    while (i < n) {
+        char c = s[i];
+        if (c==' '||c=='\t') { int j=i+1; while (j<n && (s[j]==' '||s[j]=='\t')) ++j; push(out,i,j,TokenKind::Whitespace); i=j; continue; }
+        if (c=='#') { push(out,i,n,TokenKind::Comment); break; }
+        // Strings: triple quotes and single-line
+        if (c=='"' || c=='\'') {
+            char q=c;
+            // triple?
+            if (i+2 < n && s[i+1]==q && s[i+2]==q) {
+                std::string delim(3, q);
+                int j = i+3; // search for closing triple
+                auto pos = s.find(delim, static_cast<std::size_t>(j));
+                if (pos == std::string::npos) {
+                    push(out,i,n,TokenKind::String);
+                    state.in_raw_string = true; state.raw_delim = delim; return state;
+                } else {
+                    int end = static_cast<int>(pos + 3);
+                    push(out,i,end,TokenKind::String); i=end; continue;
+                }
+            } else {
+                int j=i+1; bool esc=false; while (j<n) { char d=s[j++]; if (esc){esc=false; continue;} if (d=='\\'){esc=true; continue;} if (d==q) break; }
+                push(out,i,j,TokenKind::String); i=j; continue;
+            }
+        }
+        if (std::isdigit(static_cast<unsigned char>(c))) { int j=i+1; while (j<n && (std::isalnum(static_cast<unsigned char>(s[j]))||s[j]=='.'||s[j]=='_' )) ++j; push(out,i,j,TokenKind::Number); i=j; continue; }
+        if (is_ident_start(c)) { int j=i+1; while (j<n && is_ident_char(s[j])) ++j; std::string id=s.substr(i,j-i); TokenKind k=TokenKind::Identifier; if (kws_.count(id)) k=TokenKind::Keyword; push(out,i,j,k); i=j; continue; }
+        if (std::ispunct(static_cast<unsigned char>(c))) { TokenKind k=TokenKind::Operator; if (c==':'||c==','||c=='('||c==')'||c=='['||c==']') k=TokenKind::Punctuation; push(out,i,i+1,k); ++i; continue; }
+        push(out,i,i+1,TokenKind::Default); ++i;
+    }
+    return state;
+}
+
+} // namespace kte