From bd43c075db3d89805f5c102e02f2bc854a9d9354 Mon Sep 17 00:00:00 2001
From: Alex Karle <alex@alexkarle.com>
Date: Fri, 17 Dec 2021 00:16:16 -0500
Subject: [PATCH] Simplify links, add bold, italic, and html escapes

---
 blag.c | 125 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++----------------------------------------------
 1 file changed, 79 insertions(+), 46 deletions(-)

diff --git a/blag.c b/blag.c
index 5b32436..07dab87 100644
--- a/blag.c
+++ b/blag.c
@@ -10,7 +10,7 @@
  *
  *  <p> tags around paragraphs
  *
- *  * bullets (non-nested), breaks allowed if indented
+ *  - bullets (non-nested), breaks allowed if indented
  *
  *  1. numerical lists (non-nested), breaks allowed if indented
  *
@@ -18,11 +18,11 @@
  *
  *  TAB code blocks
  *
- *  Inline `code`
+ *  Inline `code`, _italics_, and *bold*
  *
  *  Escaping via \
  *
- *  [[url|Links]]
+ *  [url Links]
  *
  * TODO:
  * -----
@@ -52,10 +52,30 @@ enum Block {
     OLIST_BREAK,
     LINK_URL_PARSE,
     LINK_DESC_PARSE,
-    POTENTIAL_LINK,
-    POTENTIAL_LINK_END
 };
 
+void putesc(int c) {
+    switch (c) {
+        case '<':
+            printf("&lt;");
+            break;
+        case '>':
+            printf("&gt;");
+            break;
+        case '&':
+            printf("&amp;");
+            break;
+        case '"':
+            printf("&quot;");
+            break;
+        case '\'':
+            printf("&#39;");
+            break;
+        default:
+            putchar(c);
+    }
+}
+
 int closeblock(int in, int hlvl) {
     if (in == HEADER) {
         in = NONE;
@@ -100,14 +120,15 @@ int parse() {
      * continue or truly be broken on a second newline (PARAGRAPH, CODE,
      * U/OLIST, etc). Several of the variable length tokens (like ordered
      * list numbers, header level, etc) enter a "PARSE" mode where special
-     * action is taken until the parsing is done (usually on ' ', but for
-     * links on '|')
+     * action is taken until the parsing is done (usually on ' ')
      */
     int c;
     enum Block in = NONE;
     enum Block in_link = NONE;
     int hlvl = 0;
-    int in_code;
+    int in_code = 0;
+    int in_ital = 0;
+    int in_bold = 0;
     int escape = 0;
     while ((c = getchar()) != EOF) {
         /* Handle Escapes before all else */
@@ -116,18 +137,11 @@ int parse() {
                 in = PARAGRAPH;
                 printf("<p>\n");
             }
-            putchar(c);
+            putesc(c);
             escape = 0;
             continue;
         }
         
-        /* Reset special "potential" states */
-        if (c != '[' && in_link == POTENTIAL_LINK) {
-            in_link = NONE;
-        } else if (c != ']' && in_link == POTENTIAL_LINK_END) {
-            in_link = NONE;
-        }
-
         /* Handle unique state changes by char */
         switch (c) {
             case '\\':
@@ -141,7 +155,7 @@ int parse() {
                     hlvl++;
                 }  else {
                     /* not a special # */
-                    putchar(c);
+                    putesc(c);
                 }
                 break;
             case ' ':
@@ -168,17 +182,48 @@ int parse() {
                 } else if (in == OLIST_BREAK) {
                     /* assume it's a continuation! */
                     in = OLIST;
+                } else if (in_link == LINK_URL_PARSE) {
+                    in_link = LINK_DESC_PARSE;
+                    printf("\">");
                 } else {
-                    putchar(c);
+                    putesc(c);
                 }
                 break;
             case '`':
-                if (in_code) {
-                    printf("</code>");
-                    in_code = 0;
+                if (in_link == NONE) {
+                    if (in_code) {
+                        printf("</code>");
+                        in_code = 0;
+                    } else {
+                        printf("<code>");
+                        in_code = 1;
+                    }
+                }
+                break;
+            case '*':
+                if (!in_code && in_link == NONE) {
+                    if (in_bold) {
+                        printf("</strong>");
+                        in_bold = 0;
+                    } else {
+                        printf("<strong>");
+                        in_bold = 1;
+                    }
+                } else {
+                    putesc(c);
+                }
+                break;
+            case '_':
+                if (!in_code && in_link == NONE) {
+                    if (in_ital) {
+                        printf("</em>");
+                        in_ital = 0;
+                    } else {
+                        printf("<em>");
+                        in_ital = 1;
+                    }
                 } else {
-                    printf("<code>");
-                    in_code = 1;
+                    putesc(c);
                 }
                 break;
             case '\t':
@@ -188,7 +233,7 @@ int parse() {
                 } else if (in == CODE_BREAK) {
                     in = CODE;
                 } else {
-                    putchar(c);
+                    putesc(c);
                 }
                 break;
             case '>':
@@ -198,13 +243,11 @@ int parse() {
                 } else if (in == QUOTE_BREAK) {
                     in = QUOTE;
                 } else {
-                    putchar(c);
+                    putesc(c);
                 }
                 break;
             case '[':
                 if (in_link == NONE) {
-                    in_link = POTENTIAL_LINK;
-                } else if (in_link == POTENTIAL_LINK) {
                     if (in == NONE) {
                         /* Assume this is a new paragraph */
                         in = PARAGRAPH;
@@ -214,31 +257,21 @@ int parse() {
                     in_link = LINK_URL_PARSE;
                     printf("<a href=\"");
                 } else if (in_link == LINK_URL_PARSE) {
-                    /* TODO: save to linkbuf to support [[url]] links? */
-                    putchar(c);
+                    /* TODO: save to linkbuf to support [url] links? */
+                    putesc(c);
                 } else {
-                    putchar(c);
-                }
-                break;
-            case '|':
-                if (in_link == LINK_URL_PARSE) {
-                    in_link = LINK_DESC_PARSE;
-                    printf("\">");
-                } else {
-                    putchar(c);
+                    putesc(c);
                 }
                 break;
             case ']':
                 if (in_link == LINK_DESC_PARSE) {
-                    in_link = POTENTIAL_LINK_END;
-                } else if (in_link == POTENTIAL_LINK_END) {
                     in_link = NONE;
                     printf("</a>");
                 } else {
-                    putchar(c);
+                    putesc(c);
                 }
                 break;
-            case '*':
+            case '-':
                 if (in == NONE) {
                     in = ULIST_START;
                 } else if (in == ULIST_START || in == ULIST_PARSE) {
@@ -247,7 +280,7 @@ int parse() {
                     /* next list item */
                     in = ULIST_PARSE;
                 } else {
-                    putchar(c);
+                    putesc(c);
                 }
                 break;
             case '1':
@@ -268,13 +301,13 @@ int parse() {
                     /* next list item */
                     in = OLIST_PARSE;
                 } else {
-                    putchar(c);
+                    putesc(c);
                 }
                 break;
             case '\n':
                 in = closeblock(in, hlvl);
                 if (in != ULIST_BREAK && in != OLIST_BREAK) {
-                    putchar(c);
+                    putesc(c);
                 }
                 break;
             default:
@@ -286,7 +319,7 @@ int parse() {
                     /* We thought it might be the end, but it aint! */
                     in = PARAGRAPH;
                 }
-                putchar(c);
+                putesc(c);
                 break;
         }
     }
--
libgit2 1.1.1