Add genre tracking and year-in-review improvements

Adds genre field to Film model with TMDB enrichment. Genres populate from
TMDB detail fetch during add/edit and bulk enrichment. Genre metadata displays
on film cards, detail page (Production section), stats page (top genres panel),
and year-in-review (by decade and genre breakdowns).

Auto-detects rewatches when adding films via TMDB autocomplete - if a film with
the same TMDB ID already exists in diary, pre-fills rewatch checkbox and count.
Rewatch count now displays on film cards as "Rewatch #N".

Stats page now shows:
- Top genres (most watched)
- Film decades (sorted chronologically)
- Already shows: directors, companions, star distribution, rewatch rate

Year-in-review shows decades and genres alongside monthly activity and companions.

Bulk enrichment endpoint (/data/enrich-posters) now fetches missing genre
metadata along with posters and TMDB IDs.

Co-Authored-By: Claude Haiku 4.5 <noreply@anthropic.com>

1 files changed, 37 insertions, 0 deletions

diff --git a/routers/stats.py b/routers/stats.py
index 0604646..67b5141 100644
--- a/routers/stats.py
+++ b/routers/stats.py
@@ -15,6 +15,11 @@ from services.countries import (
 )
 from services.film_people import split_credit_names
 
+def split_genre_names(genre_str: str | None) -> list[str]:
+    if not genre_str:
+        return []
+    return [name.strip() for name in genre_str.split(",") if name.strip()]
+
 router = APIRouter(tags=["stats"])
 templates = Jinja2Templates(directory="templates")
 
@@ -22,7 +27,9 @@ templates = Jinja2Templates(directory="templates")
 def _build_stats_payload(films: list[Film]) -> dict:
     countries = Counter()
     country_codes = Counter()
+    decades = Counter()
     directors = Counter()
+    genres = Counter()
     star_counts = Counter({0: 0, 1: 0, 2: 0, 3: 0})
     months = Counter()
     days = Counter()
@@ -36,6 +43,12 @@ def _build_stats_payload(films: list[Film]) -> dict:
             if iso_numeric is not None:
                 country_codes[iso_numeric] += 1
 
+        if film.year:
+            decade = (film.year // 10) * 10
+            decades[f"{decade}s"] += 1
+
+        genres.update(split_genre_names(film.genre))
+
         directors.update(split_credit_names(film.director))
 
         stars = film.stars if film.stars in {0, 1, 2, 3} else 0
@@ -83,6 +96,14 @@ def _build_stats_payload(films: list[Film]) -> dict:
             {"director": director, "count": count}
             for director, count in sorted(directors.items(), key=lambda item: (-item[1], item[0]))
         ],
+        "films_per_decade": [
+            {"decade": decade, "count": count}
+            for decade, count in sorted(decades.items(), key=lambda item: (item[0], -item[1]))
+        ],
+        "films_per_genre": [
+            {"genre": genre, "count": count}
+            for genre, count in sorted(genres.items(), key=lambda item: (-item[1], item[0]))
+        ],
         "star_distribution": [{"stars": stars, "count": star_counts[stars]} for stars in (0, 1, 2, 3)],
         "films_per_month": [
             {"month": month, "count": count}
@@ -170,6 +191,8 @@ def _year_review_payload(db: Session, year: int | None) -> dict:
             "total_watched": 0,
             "average_stars": 0,
             "most_watched_directors": [],
+            "films_per_decade": [],
+            "films_per_genre": [],
             "star_distribution": [{"stars": stars, "count": 0} for stars in (0, 1, 2, 3)],
             "films_per_month": [{"month": month_name[index], "count": 0} for index in range(1, 13)],
             "rewatch_rate": {"rewatched": 0, "total_watched": 0, "rate": 0},
@@ -186,13 +209,19 @@ def _year_review_payload(db: Session, year: int | None) -> dict:
 
     year_films = _films_for_year(diary_films, selected_year)
     countries = Counter()
+    decades = Counter()
     directors = Counter()
+    genres = Counter()
     star_counts = Counter({0: 0, 1: 0, 2: 0, 3: 0})
     months = Counter({month_index: 0 for month_index in range(1, 13)})
     watched_with = Counter()
 
     for film in year_films:
         countries.update(split_country_names(film.country))
+        if film.year:
+            decade = (film.year // 10) * 10
+            decades[f"{decade}s"] += 1
+        genres.update(split_genre_names(film.genre))
         directors.update(split_credit_names(film.director))
         stars = film.stars if film.stars in {0, 1, 2, 3} else 0
         star_counts[stars] += 1
@@ -272,6 +301,14 @@ def _year_review_payload(db: Session, year: int | None) -> dict:
             {"month": month_name[index], "count": months[index]}
             for index in range(1, 13)
         ],
+        "films_per_decade": [
+            {"decade": decade, "count": count}
+            for decade, count in sorted(decades.items(), key=lambda item: (item[0], -item[1]))
+        ],
+        "films_per_genre": [
+            {"genre": genre, "count": count}
+            for genre, count in sorted(genres.items(), key=lambda item: (-item[1], item[0]))
+        ],
         "star_distribution": [{"stars": stars, "count": star_counts[stars]} for stars in (0, 1, 2, 3)],
         "most_watched_directors": [
             {"director": director, "count": count}