From 5405ceec7fa63cbd92442b4921198bad5b7b91b2 Mon Sep 17 00:00:00 2001
From: Kai Chappell <git@kschappell.com>
Date: Thu, 29 Jan 2026 17:58:02 +0000
Subject: [PATCH] Implement HTML renderer with Jinja2

---
 .../reporting/renderers/__init__.py           |   5 +
 src/py_dvt_ate/reporting/renderers/html.py    | 100 ++++++++++++++++++
 2 files changed, 105 insertions(+)
 create mode 100644 src/py_dvt_ate/reporting/renderers/__init__.py
 create mode 100644 src/py_dvt_ate/reporting/renderers/html.py

diff --git a/src/py_dvt_ate/reporting/renderers/__init__.py b/src/py_dvt_ate/reporting/renderers/__init__.py
new file mode 100644
index 0000000..5e585f6
--- /dev/null
+++ b/src/py_dvt_ate/reporting/renderers/__init__.py
@@ -0,0 +1,5 @@
+"""Report renderers for HTML and PDF output."""
+
+from py_dvt_ate.reporting.renderers.html import HTMLRenderer
+
+__all__ = ["HTMLRenderer"]
diff --git a/src/py_dvt_ate/reporting/renderers/html.py b/src/py_dvt_ate/reporting/renderers/html.py
new file mode 100644
index 0000000..bff2930
--- /dev/null
+++ b/src/py_dvt_ate/reporting/renderers/html.py
@@ -0,0 +1,100 @@
+"""HTML renderer using Jinja2 templates.
+
+This module provides HTML rendering for test reports using Jinja2 templating.
+Templates are loaded from the package's templates directory.
+"""
+
+import base64
+import json
+from datetime import datetime
+from importlib import resources
+from pathlib import Path
+
+from jinja2 import Environment, PackageLoader, select_autoescape
+
+from py_dvt_ate import __version__
+from py_dvt_ate.reporting.exceptions import TemplateRenderError
+from py_dvt_ate.reporting.models import ReportData
+
+
+class HTMLRenderer:
+    """Renders HTML reports from ReportData using Jinja2 templates.
+
+    The renderer loads templates from the py_dvt_ate.reporting.templates package
+    and provides methods for rendering complete HTML reports.
+    """
+
+    def __init__(self) -> None:
+        """Initialise the HTML renderer with Jinja2 environment."""
+        self._env = Environment(
+            loader=PackageLoader("py_dvt_ate.reporting", "templates"),
+            autoescape=select_autoescape(["html", "xml"]),
+        )
+        self._css_content: str | None = None
+
+    def _load_css(self) -> str:
+        """Load CSS content from the templates directory."""
+        if self._css_content is None:
+            templates_pkg = resources.files("py_dvt_ate.reporting.templates")
+            css_file = templates_pkg.joinpath("styles.css")
+            self._css_content = css_file.read_text()
+        return self._css_content
+
+    def _load_logo(self, logo_path: Path | None) -> str | None:
+        """Load and encode logo image as base64.
+
+        Args:
+            logo_path: Path to logo image file.
+
+        Returns:
+            Base64-encoded image data, or None if no logo or file not found.
+        """
+        if logo_path is None or not logo_path.exists():
+            return None
+
+        try:
+            with logo_path.open("rb") as f:
+                return base64.b64encode(f.read()).decode("utf-8")
+        except OSError:
+            return None
+
+    def render(self, data: ReportData) -> str:
+        """Render a test report to HTML.
+
+        Args:
+            data: Report data containing test run, results, and charts.
+
+        Returns:
+            Complete HTML document as a string.
+
+        Raises:
+            TemplateRenderError: If template rendering fails.
+        """
+        try:
+            template = self._env.get_template("test_report.html")
+
+            # Format config JSON for display
+            config_formatted = ""
+            if data.run.config_json:
+                try:
+                    config_dict = json.loads(data.run.config_json)
+                    config_formatted = json.dumps(config_dict, indent=2)
+                except json.JSONDecodeError:
+                    config_formatted = data.run.config_json
+
+            # Prepare template context
+            context = {
+                "data": data,
+                "css_content": self._load_css(),
+                "logo_base64": self._load_logo(data.config.logo_path),
+                "company_name": data.config.company_name,
+                "version": __version__,
+                "generated_at": datetime.now().strftime("%Y-%m-%d %H:%M:%S"),
+                "config_formatted": config_formatted,
+            }
+
+            return template.render(**context)
+
+        except Exception as e:
+            msg = f"Failed to render HTML template: {e}"
+            raise TemplateRenderError(msg) from e