From 35d1a24a1fc8caaf1e9b4792dfe088d6b2399c6f Mon Sep 17 00:00:00 2001
From: Toliak <toliakpurple@gmail.com>
Date: Mon, 17 Jul 2023 23:25:56 +0300
Subject: [PATCH] wip: guillemet

---
 src/ast/parsing/lexer/function.ts       |  4 ++
 src/ast/parsing/lexer/node/guillemet.ts | 77 +++++++++++++++++++++++++
 2 files changed, 81 insertions(+)
 create mode 100644 src/ast/parsing/lexer/node/guillemet.ts

diff --git a/src/ast/parsing/lexer/function.ts b/src/ast/parsing/lexer/function.ts
index 84ae448..7318a81 100644
--- a/src/ast/parsing/lexer/function.ts
+++ b/src/ast/parsing/lexer/function.ts
@@ -455,6 +455,10 @@ const parsersByType: Record<TokenType, TokenParser[]> = {
         parseLinkSimple,
         parseList,
         parseCode,
+
+        // TODO: check the implementation
+        // parseGuillemet,
+
         parseFormulaSpan,
         parseFormulaOrLatex,
         parseLatexSpan,
diff --git a/src/ast/parsing/lexer/node/guillemet.ts b/src/ast/parsing/lexer/node/guillemet.ts
new file mode 100644
index 0000000..205dacb
--- /dev/null
+++ b/src/ast/parsing/lexer/node/guillemet.ts
@@ -0,0 +1,77 @@
+import { TokenParser } from '../struct';
+import {
+    applyVisitors,
+    findTokenClosingBracket,
+    isOpenArgumentBracket,
+    isOpenLabelBracket,
+    sliceTokenText,
+    unexpectedEof,
+} from '../index';
+import {
+    LinkNode,
+    NodeType,
+    RawNodeType,
+    TextNode,
+    TokensNode,
+} from '../../../node';
+import { TokenType } from '../../tokenizer';
+
+/**
+ * Angle bracket
+ */
+export function isOpenGuillemet(tokens: TokensNode, index: number): boolean {
+    const token = tokens.tokens[index];
+    return token.type === TokenType.JoinableSpecial && token.text == '<<<';
+}
+
+export const parseGuillemet: TokenParser = function (tokens, index) {
+    const token = tokens.tokens[index];
+    if (!isOpenGuillemet(tokens, index)) {
+        return null;
+    }
+
+    const closingBracketResult = findTokenClosingBracket(tokens, index);
+    if (!closingBracketResult) {
+        return unexpectedEof(
+            tokens,
+            index,
+            'Unable to find closing bracket for guillemet',
+        );
+    }
+
+    const hrefStartToken = tokens.tokens[index + 1];
+    const hrefStopToken = tokens.tokens[closingBracketResult.index - 1];
+    const hrefText = tokens.tokens
+        .slice(index + 1, closingBracketResult.index)
+        .map(v => v.text)
+        .join('');
+
+    const hrefTextNode: TextNode = {
+        type: NodeType.Text,
+        text: hrefText,
+        parent: null,
+        pos: {
+            start: hrefStartToken.pos,
+            end: hrefStopToken.pos + hrefStopToken.text.length,
+        },
+    };
+
+    const endToken = closingBracketResult.token;
+    const linkNode: LinkNode = {
+        type: NodeType.Link,
+        parent: tokens.parent,
+        pos: {
+            start: token.pos,
+            end: endToken.pos + endToken.text.length,
+        },
+        children: [],
+        href: hrefTextNode,
+    };
+    hrefTextNode.parent = linkNode;
+
+    return {
+        nodes: [linkNode],
+        index: closingBracketResult.index + 1,
+        diagnostic: [],
+    };
+};