feat: implement mosaic cover generation logic

Made-with: Cursor

tests/test_cover.py

@@ -1,19 +1,16 @@
 import json
 import os
-from collections import Counter
 from datetime import date
-from unittest.mock import patch, MagicMock
+from unittest.mock import patch
 from io import BytesIO
 from PIL import Image as PILImage, ImageDraw, ImageFont
 
 from src.cover import (
     generate_programmatic_cover,
-    generate_ai_cover,
+    generate_mosaic_cover,
     generate_cover,
-    _get_dominant_category,
     _truncate_to_width,
     _get_font,
-    CATEGORY_PROMPTS,
 )
 
 
@@ -46,54 +43,31 @@ def test_programmatic_cover_no_headlines(tmp_path):
     assert img.size == (480, 800)
 
 
-def test_ai_cover_is_portrait(tmp_path):
-    fake_img = PILImage.new("RGB", (480, 800), color="blue")
-    buf = BytesIO()
-    fake_img.save(buf, format="JPEG")
-    fake_bytes = buf.getvalue()
+def test_generate_mosaic_cover_single_image(tmp_path):
+    # Create a dummy image
+    img_path = str(tmp_path / "dummy.jpg")
+    img = PILImage.new("RGB", (1000, 500), color="red")
+    img.save(img_path)
 
-    mock_response = MagicMock()
-    mock_response.content = fake_bytes
-    mock_response.raise_for_status = MagicMock()
+    output_dir = str(tmp_path)
+    week_start = date(2026, 4, 6)
+    week_end = date(2026, 4, 12)
+    headlines = ["Test Headline"]
 
-    with patch("src.cover.requests.get", return_value=mock_response):
-        path = generate_ai_cover(
-            output_dir=str(tmp_path),
-            week_start=date(2026, 4, 6),
-            week_end=date(2026, 4, 12),
-            headlines=["Test Headline"],
-            categories=["Government"],
-        )
+    cover_path = generate_mosaic_cover(output_dir, week_start, week_end, headlines, [img_path])
 
-    assert os.path.exists(path)
-    img = PILImage.open(path)
-    assert img.format == "JPEG"
-    assert img.size == (480, 800)
-
-
-def test_ai_cover_falls_back_to_programmatic(tmp_path):
-    with patch("src.cover.requests.get", side_effect=Exception("API down")):
-        path = generate_ai_cover(
-            output_dir=str(tmp_path),
-            week_start=date(2026, 4, 6),
-            week_end=date(2026, 4, 12),
-            headlines=["Test"],
-            categories=["Government"],
-        )
-
-    assert os.path.exists(path)
-    img = PILImage.open(path)
-    assert img.format == "JPEG"
-    assert img.size == (480, 800)
+    assert os.path.exists(cover_path)
+    with PILImage.open(cover_path) as result_img:
+        assert result_img.size == (480, 800)
 
 
 def test_generate_cover_dispatches(tmp_path):
-    with patch("src.cover.generate_ai_cover") as mock_ai:
-        mock_ai.return_value = "/fake/ai.jpg"
-        result = generate_cover("ai", str(tmp_path), date(2026, 4, 6),
-                                date(2026, 4, 12), ["A"], ["Government"])
-        assert result == "/fake/ai.jpg"
-        mock_ai.assert_called_once()
+    with patch("src.cover.generate_mosaic_cover") as mock_mosaic:
+        mock_mosaic.return_value = "/fake/mosaic.jpg"
+        result = generate_cover("mosaic", str(tmp_path), date(2026, 4, 6),
+                                date(2026, 4, 12), ["A"], ["/x/a.jpg"])
+        assert result == "/fake/mosaic.jpg"
+        mock_mosaic.assert_called_once()
 
     with patch("src.cover.generate_programmatic_cover") as mock_prog:
         mock_prog.return_value = "/fake/text.jpg"
@@ -103,17 +77,6 @@ def test_generate_cover_dispatches(tmp_path):
         mock_prog.assert_called_once()
 
 
-def test_get_dominant_category():
-    assert _get_dominant_category(["Government", "Government", "Culture"]) == "Government"
-    assert _get_dominant_category(["Culture", "Government"]) == "Culture"
-    assert _get_dominant_category([]) == "Default"
-
-
-def test_category_prompts_include_massachusetts():
-    for category, prompt in CATEGORY_PROMPTS.items():
-        assert "Massachusetts" in prompt, f"Prompt for {category} missing 'Massachusetts'"
-
-
 def test_truncate_to_width_respects_pixel_budget():
     font = _get_font(18)
     short = "Short text"