feat: add media filtering by tag name

libertas-frontend/src/routes/media/index.tsx

@@ -138,6 +138,7 @@ function MediaPage() {
             </SelectTrigger>
             <SelectContent>
               <SelectItem value="original_filename">Filename</SelectItem>
+              <SelectItem value="tag.name">Tag</SelectItem>
               <SelectItem value="metadata.Make">Make</SelectItem>
               <SelectItem value="metadata.Model">Model</SelectItem>
               <SelectItem value="metadata.ISO">ISO</SelectItem>

libertas_infra/src/query_builder.rs

@@ -273,6 +273,55 @@ impl FilterStrategy for MetadataFilterStrategy {
     }
 }
 
+pub struct TagFilterStrategy;
+
+impl FilterStrategy for TagFilterStrategy {
+    fn can_handle(&self, field: &str) -> bool {
+        field == "tag.name"
+    }
+
+    fn apply_join<'a>(
+        &self,
+        _query: &mut SqlxQueryBuilder<'a, sqlx::Postgres>,
+        _field: &'a str,
+    ) -> CoreResult<()> {
+        // We use EXISTS subqueries in apply_condition, so no main query join is needed.
+        Ok(())
+    }
+
+    fn apply_condition<'a>(
+        &self,
+        query: &mut SqlxQueryBuilder<'a, sqlx::Postgres>,
+        condition: &'a libertas_core::schema::FilterCondition,
+    ) -> CoreResult<()> {
+        use libertas_core::schema::FilterOperator;
+
+        let op = match condition.operator {
+            FilterOperator::Eq => "=",
+            FilterOperator::Neq => "!=",
+            FilterOperator::Like => "ILIKE",
+            FilterOperator::Gt => ">",
+            FilterOperator::Lt => "<",
+            FilterOperator::Gte => ">=",
+            FilterOperator::Lte => "<=",
+        };
+
+        query.push(" AND EXISTS (SELECT 1 FROM media_tags mt JOIN tags t ON mt.tag_id = t.id WHERE mt.media_id = media.id AND t.name ");
+        query.push(op);
+        query.push(" ");
+
+        if condition.operator == FilterOperator::Like {
+            query.push_bind(format!("%{}%", condition.value));
+        } else {
+            query.push_bind(&condition.value);
+        }
+
+        query.push(" ) ");
+
+        Ok(())
+    }
+}
+
 pub trait QueryBuilder<T> {
     fn apply_options_to_query<'a>(
         &self,

libertas_infra/src/repositories/media_repository.rs

@@ -29,13 +29,18 @@ impl PostgresMediaRepository {
         allowed_columns.push("date_taken".to_string());
 
         let sort_strategies: Vec<Box<dyn crate::query_builder::SortStrategy>> = vec![
-            Box::new(crate::query_builder::StandardSortStrategy::new(allowed_columns.clone())),
+            Box::new(crate::query_builder::StandardSortStrategy::new(
+                allowed_columns.clone(),
+            )),
             Box::new(crate::query_builder::MetadataSortStrategy),
         ];
 
         let filter_strategies: Vec<Box<dyn crate::query_builder::FilterStrategy>> = vec![
-            Box::new(crate::query_builder::StandardFilterStrategy::new(allowed_columns)),
+            Box::new(crate::query_builder::StandardFilterStrategy::new(
+                allowed_columns,
+            )),
             Box::new(crate::query_builder::MetadataFilterStrategy),
+            Box::new(crate::query_builder::TagFilterStrategy),
         ];
 
         Self {
@@ -125,9 +130,8 @@ impl MediaRepository for PostgresMediaRepository {
         count_query.push(" WHERE media.owner_id = ");
         count_query.push_bind(user_id);
 
-        let (mut count_query, metadata_filter_count) = self
-            .query_builder
-            .apply_conditions(count_query, options)?;
+        let (mut count_query, metadata_filter_count) =
+            self.query_builder.apply_conditions(count_query, options)?;
 
         if metadata_filter_count > 0 {
             count_query.push(" GROUP BY media.id ");
@@ -154,9 +158,8 @@ impl MediaRepository for PostgresMediaRepository {
         data_query.push(" WHERE media.owner_id = ");
         data_query.push_bind(user_id);
 
-        let (mut data_query, metadata_filter_count) = self
-            .query_builder
-            .apply_conditions(data_query, options)?;
+        let (mut data_query, metadata_filter_count) =
+            self.query_builder.apply_conditions(data_query, options)?;
 
         if metadata_filter_count > 0 {
             data_query.push(" GROUP BY media.id ");
@@ -198,9 +201,8 @@ impl MediaRepository for PostgresMediaRepository {
         count_query.push(" WHERE fr.person_id = ");
         count_query.push_bind(person_id);
 
-        let (mut count_query, _metadata_filter_count) = self
-            .query_builder
-            .apply_conditions(count_query, options)?;
+        let (mut count_query, _metadata_filter_count) =
+            self.query_builder.apply_conditions(count_query, options)?;
 
         let total_items_result = count_query
             .build_query_scalar()
@@ -222,9 +224,8 @@ impl MediaRepository for PostgresMediaRepository {
         data_query.push(" WHERE fr.person_id = ");
         data_query.push_bind(person_id);
 
-        let (mut data_query, _metadata_filter_count) = self
-            .query_builder
-            .apply_conditions(data_query, options)?;
+        let (mut data_query, _metadata_filter_count) =
+            self.query_builder.apply_conditions(data_query, options)?;
 
         data_query.push(" GROUP BY media.id ");