feat: Provide direct link to text (#162)

app/src/chat_api.py

@@ -24,6 +24,7 @@
 from src.db.models.document import Subsection
 from src.generate import ChatHistory
 from src.healthcheck import HealthCheck, health
+from src.util.string_utils import format_highlighted_uri
 
 logger = logging.getLogger(__name__)
 router = APIRouter(prefix="/api", tags=["Chat API"])
@@ -202,12 +203,13 @@ class Citation(BaseModel):
     @staticmethod
     def from_subsection(subsection: Subsection) -> "Citation":
         chunk = subsection.chunk
+        highlighted_text_src = format_highlighted_uri(chunk.document.source, subsection.text)
         return Citation(
             citation_id=f"citation-{subsection.id}",
             source_id=str(chunk.document.id),
             source_name=chunk.document.name,
             page_number=chunk.page_number,
-            uri=chunk.document.source,
+            uri=highlighted_text_src,
             headings=subsection.text_headings,
             citation_text=subsection.text,
         )

app/src/util/string_utils.py

@@ -179,3 +179,16 @@ def parse_heading_markdown(md: str) -> tuple[int, str]:
 def remove_links(markdown: str) -> str:
     # Remove markdown links, e.g., `[This is a link](https://example.com/relative/path) and [another](https://example.com/absolute/path)` -> `This is a link and another`
     return re.sub(r"\[([^\]]+)\]\([^\)]+\)", r"\1", markdown)
+
+
+def format_highlighted_uri(source_url: str | None, subsection_text: str) -> str | None:
+    if not source_url:
+        return None
+    citation_without_special_chars = re.sub(r"\W+", " ", subsection_text).strip()
+    citation_arr = citation_without_special_chars.split(" ")
+    formatted_text_to_highlight = "%20".join(citation_arr[:5]) + "," + "%20".join(citation_arr[-5:])
+    return (
+        (source_url[:-1] if source_url.endswith("/") else source_url)
+        + "#:~:text="
+        + formatted_text_to_highlight
+    )

app/tests/src/util/test_string_utils.py

@@ -1,6 +1,7 @@
 import pytest
 
 from src.util.string_utils import (
+    format_highlighted_uri,
     headings_as_markdown,
     parse_heading_markdown,
     remove_links,
@@ -108,3 +109,14 @@ def test_parse_heading_markdown():
 def test_remove_links():
     markdown = "[This is a link](relative/path) and [another](https://example.com/absolute/path)"
     assert remove_links(markdown) == "This is a link and another"
+
+
+def test_citation_formatting():
+    subsection_text = "* [CalFresh](https://www.getcalfresh.org/?source=edd) (formerly known as Food Stamps)  \n  CalFresh provides monthly food assistance to people and families with low income, including those who lost their job because of the pandemic. Visit [GetCalFresh.org](https://www.getcalfresh.org/?source=edd) to apply online.\n* [California Association of Food Banks](http://www.cafoodbanks.org/)  \n  In California, federal, state, and local community organizations coordinate to make sure that groceries are available at local food banks.\n* [Free Summer Lunch Programs](http://www.cde.ca.gov/ds/sh/sn/summersites.asp)  \n  Free lunches are available to all children under 18, regardless of income.\n* [School Meals](https://www.fns.usda.gov/school-meals/applying-free-and-reduced-price-school-meals)  \n  Free or reduced-price breakfast and lunch at public schools when in session.\n* [Women, Infants and Children (WIC) Program](https://www.cdph.ca.gov/Programs/CFH/DWICSN/Pages/Program-Landing1.aspx)  \n  Pregnant women and children under age 5 receive nutrition support at WIC."
+    source_url = "https://edd.ca.gov/en/disability/options_to_file_for_pfl_benefits/"
+    highlighted_url = format_highlighted_uri(source_url, subsection_text)
+
+    assert (
+        highlighted_url
+        == "https://edd.ca.gov/en/disability/options_to_file_for_pfl_benefits#:~:text=CalFresh%20https%20www%20getcalfresh%20org,receive%20nutrition%20support%20at%20WIC"
+    )