refactor HTML and Markdown parsers

Author: ZeN220

pyrogram/parser/combined.py

@@ -0,0 +1,73 @@
+from __future__ import annotations
+
+from typing import List, Optional
+
+import pyrogram
+from pyrogram.types.messages_and_media.message_entity import MessageEntity
+
+from .rendering import make_entity_list
+from .html import HTML
+from .markdown import Markdown
+from .types import ParseResult
+from .utils import add_surrogates
+
+
+class CombinedParser:
+    def __init__(self, client: Optional["pyrogram.Client"]) -> None:
+        self.client = client
+        self.html = HTML(client)
+        self.markdown = Markdown(client)
+
+    async def parse(self, text: str) -> ParseResult:
+        html_result = await self.html.parse(text)
+        source = html_result["message"]
+        html_entities = list(html_result["entities"] or [])
+
+        markdown_result = await self.markdown.parse(source)
+        message = markdown_result["message"]
+        markdown_entities = list(markdown_result["entities"] or [])
+
+        if html_entities:
+            mapping = self._build_subsequence_map(add_surrogates(source), add_surrogates(message))
+            html_entities = [self._remap_entity(entity, mapping) for entity in html_entities]
+
+        entities = [*markdown_entities, *html_entities]
+        entities.sort(key=lambda entity: (entity.offset, entity.length))
+
+        return {
+            "message": message,
+            "entities": make_entity_list(entities)
+        }
+
+    @staticmethod
+    def _build_subsequence_map(source: str, plain: str) -> List[int]:
+        mapping: List[int] = [0] * (len(source) + 1)
+        plain_index = 0
+
+        for source_index, char in enumerate(source):
+            mapping[source_index] = plain_index
+
+            if plain_index < len(plain) and char == plain[plain_index]:
+                plain_index += 1
+
+            mapping[source_index + 1] = plain_index
+
+        return mapping
+
+    @staticmethod
+    def _remap_entity(entity: MessageEntity, mapping: List[int]) -> MessageEntity:
+        start = mapping[entity.offset]
+        end = mapping[entity.offset + entity.length]
+
+        return MessageEntity(
+            type=entity.type,
+            offset=start,
+            length=end - start,
+            url=entity.url,
+            user=entity.user,
+            language=entity.language,
+            custom_emoji_id=entity.custom_emoji_id,
+            expandable=entity.expandable,
+            unix_time=entity.unix_time,
+            date_time_format=entity.date_time_format
+        )