Update UI for Sitemap to show last 20 and scroll to button.

app.py

@@ -2,15 +2,18 @@ from __future__ import annotations
 
 import contextlib
 import csv
+import html
 import importlib.util
 import io
 import os
 import re
 import sys
 import time
+from collections import deque
 from pathlib import Path
 
 import streamlit as st
+import streamlit.components.v1 as components
 
 
 ROOT_DIR = Path(__file__).resolve().parent
@@ -58,17 +61,26 @@ def read_csv_preview(csv_bytes: bytes, limit: int = 200) -> list[dict[str, str]]
 
 
 class StreamlitOutputBuffer(io.TextIOBase):
-    def __init__(self, placeholder, *, height: int = 220, throttle_seconds: float = 0.2) -> None:
+    def __init__(self, placeholder, *, height: int = 220, throttle_seconds: float = 0.2, max_lines: int = 20) -> None:
         self.placeholder = placeholder
         self.height = height
         self.throttle_seconds = throttle_seconds
-        self.parts: list[str] = []
+        self.max_lines = max_lines
+        self.lines: deque[str] = deque(maxlen=max_lines)
+        self.current_line = ""
         self.last_render = 0.0
 
     def write(self, text: str) -> int:
         if not text:
             return 0
-        self.parts.append(text)
+        normalized = text.replace("\r\n", "\n").replace("\r", "\n")
+        for chunk in normalized.splitlines(keepends=True):
+            if chunk.endswith("\n"):
+                self.current_line += chunk[:-1]
+                self.lines.append(self.current_line)
+                self.current_line = ""
+            else:
+                self.current_line += chunk
         now = time.monotonic()
         if "\n" in text or (now - self.last_render) >= self.throttle_seconds:
             self.render()
@@ -79,15 +91,40 @@ class StreamlitOutputBuffer(io.TextIOBase):
 
     def render(self) -> None:
         self.last_render = time.monotonic()
-        self.placeholder.text_area(
-            "Scan Details",
-            value="".join(self.parts),
-            height=self.height,
-            disabled=True,
+        visible_lines = list(self.lines)
+        if self.current_line:
+            visible_lines.append(self.current_line)
+        visible_lines = visible_lines[-self.max_lines :]
+        content = html.escape("\n".join(visible_lines))
+        self.placeholder.caption("Scan Details")
+        components.html(
+            f"""
+            <div id="scan-details" style="
+                height: {self.height}px;
+                overflow-y: auto;
+                white-space: pre-wrap;
+                font-family: monospace;
+                font-size: 0.9rem;
+                padding: 0.75rem;
+                border: 1px solid rgba(49, 51, 63, 0.2);
+                border-radius: 0.5rem;
+                background: white;
+            ">{content}</div>
+            <script>
+                const el = document.getElementById("scan-details");
+                if (el) {{
+                    el.scrollTop = el.scrollHeight;
+                }}
+            </script>
+            """,
+            height=self.height + 16,
         )
 
     def getvalue(self) -> str:
-        return "".join(self.parts)
+        visible_lines = list(self.lines)
+        if self.current_line:
+            visible_lines.append(self.current_line)
+        return "\n".join(visible_lines[-self.max_lines :])
 
 
 def render_sitemap_tab() -> None: