From 6167a9848cd18b0050497871e9e979e65f5a303b Mon Sep 17 00:00:00 2001
From: QuietMisdreavus <victoria@quietmisdreavus.net>
Date: Fri, 31 Dec 2021 20:42:22 -0700
Subject: [PATCH] add parenthesis version of superscript

---
 extensions/superscript.c | 165 ++++++++++++++++++++++++++++++++-------
 test/spec.txt            |   6 +-
 2 files changed, 138 insertions(+), 33 deletions(-)

diff --git a/extensions/superscript.c b/extensions/superscript.c
index 64112cb9d..f6c8cc009 100644
--- a/extensions/superscript.c
+++ b/extensions/superscript.c
@@ -3,50 +3,154 @@
 #include <parser.h>
 #include <render.h>
 
+static cmark_chunk *S_get_node_literal_chunk(cmark_node *node) {
+  if (node == NULL) {
+    return NULL;
+  }
+
+  switch (node->type) {
+  case CMARK_NODE_HTML_BLOCK:
+  case CMARK_NODE_TEXT:
+  case CMARK_NODE_HTML_INLINE:
+  case CMARK_NODE_CODE:
+  case CMARK_NODE_FOOTNOTE_REFERENCE:
+    return &node->as.literal;
+
+  case CMARK_NODE_CODE_BLOCK:
+    return &node->as.code.literal;
+
+  default:
+    break;
+  }
+
+  return NULL;
+}
+
+static bool S_node_contains_space(cmark_node *node) {
+  cmark_chunk *chunk = S_get_node_literal_chunk(node);
+  if (chunk)
+    return (cmark_chunk_strchr(chunk, ' ', 0) != chunk->len);
+  else
+    return false;
+}
+
+static bool S_children_contain_space(cmark_node *parent) {
+  cmark_node *node = parent->first_child;
+  while (node) {
+    if (S_node_contains_space(node)) {
+      return true;
+    }
+    node = node->next;
+  }
+
+  return false;
+}
+
 cmark_node_type CMARK_NODE_SUPERSCRIPT;
 
 static cmark_node *match(cmark_syntax_extension *self, cmark_parser *parser,
                          cmark_node *parent, unsigned char character,
                          cmark_inline_parser *inline_parser) {
   cmark_node *res = NULL;
-  int startpos = cmark_inline_parser_get_offset(inline_parser) + 1;
-  int endpos = startpos;
-
-  if (character != '^')
-    return NULL;
-
-  // TODO: long-form parsing with parens
-  if (cmark_inline_parser_peek_at(inline_parser, endpos) == '(')
-    return NULL;
+  int initpos = cmark_inline_parser_get_offset(inline_parser);
+
+  if (character == '^') {
+    if (cmark_inline_parser_peek_at(inline_parser, initpos + 1) == '(') {
+      res = cmark_node_new_with_mem(CMARK_NODE_TEXT, parser->mem);
+      cmark_node_set_literal(res, "^(");
+      res->start_line = res->end_line = cmark_inline_parser_get_line(inline_parser);
+      res->start_column = cmark_inline_parser_get_column(inline_parser);
+      res->end_column = res->start_column + 2;
+
+      cmark_inline_parser_set_offset(inline_parser, initpos + 2);
+      cmark_inline_parser_push_delimiter(inline_parser, '^', true, false, res);
+    } else {
+      int startpos = initpos + 1;
+      int endpos = startpos;
+
+      cmark_chunk *chunk = cmark_inline_parser_get_chunk(inline_parser);
+      bufsize_t len = chunk->len;
+
+      while (endpos < len) {
+        unsigned char seekchar = cmark_inline_parser_peek_at(inline_parser, endpos);
+        if (cmark_isspace(seekchar) || (cmark_ispunct(seekchar) && seekchar != '^'))
+          break;
+        endpos++;
+      }
+
+      int nodelen = endpos - startpos;
+
+      // don't emit an empty node
+      if (nodelen == 0)
+        return NULL;
+
+      cmark_inline_parser_set_offset(inline_parser, startpos);
+
+      res = cmark_node_new_with_mem_and_ext(CMARK_NODE_SUPERSCRIPT, parser->mem, self);
+      res->as.literal = cmark_chunk_dup(chunk, startpos, nodelen);
+      res->start_line = cmark_inline_parser_get_line(inline_parser);
+      res->start_column = cmark_inline_parser_get_column(inline_parser);
+
+      cmark_inline_parser_set_offset(inline_parser, endpos);
+
+      res->end_line = cmark_inline_parser_get_line(inline_parser);
+      res->end_column = cmark_inline_parser_get_column(inline_parser);
+
+      const char *text = cmark_chunk_to_cstr(parser->mem, &res->as.literal);
+      cmark_node_set_string_content(res, text);
+
+      cmark_parse_inlines(parser, res, parser->refmap, parser->options);
+    }
+  } else if (character == ')') {
+    res = cmark_node_new_with_mem(CMARK_NODE_TEXT, parser->mem);
+    cmark_node_set_literal(res, ")");
+    res->start_line = res->end_line = cmark_inline_parser_get_line(inline_parser);
+    res->start_column = cmark_inline_parser_get_column(inline_parser);
+    res->end_column = res->start_column + 1;
+
+    cmark_inline_parser_set_offset(inline_parser, initpos + 1);
+    cmark_inline_parser_push_delimiter(inline_parser, '^', false, true, res);
+  }
 
-  cmark_chunk *chunk = cmark_inline_parser_get_chunk(inline_parser);
-  bufsize_t len = chunk->len;
+  return res;
+}
 
-  while (endpos < len && !cmark_isspace(cmark_inline_parser_peek_at(inline_parser, endpos)))
-    endpos++;
+static delimiter *insert(cmark_syntax_extension *self, cmark_parser *parser,
+                         cmark_inline_parser *inline_parser, delimiter *opener,
+                         delimiter *closer) {
+  cmark_node *superscript;
+  cmark_node *tmp, *next;
+  delimiter *delim, *tmp_delim;
+  delimiter *res = closer->next;
 
-  int nodelen = endpos - startpos;
+  superscript = opener->inl_text;
 
-  // don't emit an empty node
-  if (nodelen == 0)
-    return NULL;
+  if (!cmark_node_set_type(superscript, CMARK_NODE_SUPERSCRIPT))
+    return res;
 
-  cmark_inline_parser_set_offset(inline_parser, startpos);
+  cmark_node_set_syntax_extension(superscript, self);
 
-  res = cmark_node_new_with_mem_and_ext(CMARK_NODE_SUPERSCRIPT, parser->mem, self);
-  res->as.literal = cmark_chunk_dup(chunk, startpos, nodelen);
-  res->start_line = cmark_inline_parser_get_line(inline_parser);
-  res->start_column = cmark_inline_parser_get_column(inline_parser);
+  tmp = cmark_node_next(opener->inl_text);
 
-  cmark_inline_parser_set_offset(inline_parser, endpos);
+  while (tmp) {
+    if (tmp == closer->inl_text)
+      break;
+    next = cmark_node_next(tmp);
+    cmark_node_append_child(superscript, tmp);
+    tmp = next;
+  }
 
-  res->end_line = cmark_inline_parser_get_line(inline_parser);
-  res->end_column = cmark_inline_parser_get_column(inline_parser);
+  superscript->end_column = closer->inl_text->start_column + closer->inl_text->as.literal.len - 1;
+  cmark_node_free(closer->inl_text);
 
-  const char *text = cmark_chunk_to_cstr(parser->mem, &res->as.literal);
-  cmark_node_set_string_content(res, text);
+  delim = closer;
+  while (delim != NULL && delim != opener) {
+    tmp_delim = delim->previous;
+    cmark_inline_parser_remove_delimiter(inline_parser, delim);
+    delim = tmp_delim;
+  }
 
-  cmark_parse_inlines(parser, res, parser->refmap, parser->options);
+  cmark_inline_parser_remove_delimiter(inline_parser, opener);
 
   return res;
 }
@@ -67,7 +171,7 @@ static int can_contain(cmark_syntax_extension *extension, cmark_node *node,
 static void commonmark_render(cmark_syntax_extension *extension,
                               cmark_renderer *renderer, cmark_node *node,
                               cmark_event_type ev_type, int options) {
-  bool should_wrap = (cmark_strbuf_strchr(&node->content, ' ', 0) != -1);
+  bool should_wrap = S_children_contain_space(node);
   bool entering = (ev_type == CMARK_EVENT_ENTER);
   if (entering) {
     if (should_wrap)
@@ -129,10 +233,11 @@ cmark_syntax_extension *create_superscript_extension(void) {
   CMARK_NODE_SUPERSCRIPT = cmark_syntax_extension_add_node(1);
 
   cmark_syntax_extension_set_match_inline_func(ext, match);
-//  cmark_syntax_extension_set_inline_from_delim_func(ext, insert);
+  cmark_syntax_extension_set_inline_from_delim_func(ext, insert);
 
   cmark_mem *mem = cmark_get_default_mem_allocator();
   special_chars = cmark_llist_append(mem, special_chars, (void *)'^');
+  special_chars = cmark_llist_append(mem, special_chars, (void *)')');
   cmark_syntax_extension_set_special_inline_chars(ext, special_chars);
 
   cmark_syntax_extension_set_emphasis(ext, 1);
diff --git a/test/spec.txt b/test/spec.txt
index ce9bbed37..1930cc933 100644
--- a/test/spec.txt
+++ b/test/spec.txt
@@ -7756,7 +7756,7 @@ Superscripting a whole ^word
 In addition, if you would like to raise more than one word, you can add
 parentheses around the text you would like to style in a superscript:
 
-```````````````````````````````` example superscript disabled
+```````````````````````````````` example superscript
 I would like to ^(raise this whole phrase), please.
 .
 <p>I would like to <sup>raise this whole phrase</sup>, please.</p>
@@ -7770,10 +7770,10 @@ z = t^x^2
 <p>z = t<sup>x<sup>2</sup></sup></p>
 ````````````````````````````````
 
-```````````````````````````````` example superscript disabled
+```````````````````````````````` example superscript
 For my next trick, I will ^(raise my text ^(twice)), at the same time!
 .
-<p>For my next trick, I will <sup>raise my text<sup>twice</sup></sup>, at the same time!</p>
+<p>For my next trick, I will <sup>raise my text <sup>twice</sup></sup>, at the same time!</p>
 ````````````````````````````````
 
 </div>