add markdown dialect (WIP) & add strikethrough and underline font styles

2024-12-06 17:35:03 +03:00
parent 605d7e7897
commit 80e809f97f
15 changed files with 296 additions and 58 deletions
@@ -0,0 +1,109 @@
+#include "markdown.hpp"
+
+#include <sstream>
+
+#include "graphics/core/Font.hpp"
+
+using namespace markdown;
+
+template <typename CharT>
+static inline void emit(
+    CharT c, FontStylesScheme& styles, std::basic_stringstream<CharT>& ss
+) {
+    ss << c;
+    styles.map.emplace_back(styles.palette.size()-1);
+}
+
+template <typename CharT>
+static inline void emit_md(
+    CharT c, FontStylesScheme& styles, std::basic_stringstream<CharT>& ss
+) {
+    ss << c;
+    styles.map.emplace_back(0);
+}
+
+template <typename CharT>
+static inline void restyle(
+    CharT c,
+    FontStyle& style,
+    FontStylesScheme& styles,
+    std::basic_stringstream<CharT>& ss,
+    int& pos,
+    bool eraseMarkdown
+) {
+    styles.palette.push_back(style);
+    if (!eraseMarkdown) {
+        emit_md(c, styles, ss);
+    }
+    pos++;
+}
+
+template <typename CharT>
+Result<CharT> process_markdown(
+    std::basic_string_view<CharT> source, bool eraseMarkdown
+) {
+    std::basic_stringstream<CharT> ss;
+    FontStylesScheme styles {
+        // markdown                                           default
+        {{false, false, false, false, glm::vec4(1,1,1,0.5f)}, {}},
+        {}
+    };
+    FontStyle style;
+    int pos = 0;
+    while (pos < source.size()) {
+        CharT first = source[pos];
+        if (first == '\\') {
+            if (pos + 1 < source.size()) {
+                CharT second = source[++pos];
+                switch (second) {
+                    case '*':
+                    case '_':
+                    case '~':
+                        if (!eraseMarkdown) {
+                            emit_md(first, styles, ss);
+                        }
+                        emit(second, styles, ss);
+                        pos++;
+                        continue;
+                }
+            }
+        } else if (first == '*') {
+            if (pos + 1 < source.size() && source[pos+1] == '*') {
+                pos++;
+                if (!eraseMarkdown)
+                    emit_md(first, styles, ss);
+                style.bold = !style.bold;
+                restyle(first, style, styles, ss, pos, eraseMarkdown);
+                continue;
+            }
+            style.italic = !style.italic;
+            restyle(first, style, styles, ss, pos, eraseMarkdown);
+            continue;
+        } else if (first == '_' && pos + 1 < source.size() && source[pos+1] == '_') {
+            pos++;
+            if (!eraseMarkdown)
+                emit_md(first, styles, ss);
+            style.underline = !style.underline;
+            restyle(first, style, styles, ss, pos, eraseMarkdown);
+            continue;
+        } else if (first == '~' && pos + 1 < source.size() && source[pos+1] == '~') {
+            pos++;
+            if (!eraseMarkdown)
+                emit_md(first, styles, ss);
+            style.strikethrough = !style.strikethrough;
+            restyle(first, style, styles, ss, pos, eraseMarkdown);
+            continue;
+        }
+        emit(first, styles, ss);
+        pos++;
+    }
+    return {ss.str(), std::make_unique<FontStylesScheme>(std::move(styles))};
+}
+
+Result<char> markdown::process(std::string_view source, bool eraseMarkdown) {
+    return process_markdown(source, eraseMarkdown);
+}
+
+Result<wchar_t> markdown::process(std::wstring_view source, bool eraseMarkdown) {
+    return process_markdown(source, eraseMarkdown);
+}