[feature] Allow newly uploaded emojis to be placed in categories (#939)

* [feature] Add emoji categories GET
Serialize emojis in appropriate categories; make it possible to get categories via the admin API

* [feature] Create (or use existing) category for new emoji uploads

* fix lint issue

* update misleading line in swagger docs

5 files changed, 181 insertions, 12 deletions

diff --git a/internal/db/bundb/bundb.go b/internal/db/bundb/bundb.go
index 43e9a07c9..cf6643f6b 100644
--- a/internal/db/bundb/bundb.go
+++ b/internal/db/bundb/bundb.go
@@ -180,7 +180,7 @@ func NewBunDBService(ctx context.Context) (db.DB, error) {
 	// Create DB structs that require ptrs to each other
 	accounts := &accountDB{conn: conn, cache: accountCache}
 	status := &statusDB{conn: conn, cache: cache.NewStatusCache()}
-	emoji := &emojiDB{conn: conn, cache: cache.NewEmojiCache()}
+	emoji := &emojiDB{conn: conn, emojiCache: cache.NewEmojiCache(), categoryCache: cache.NewEmojiCategoryCache()}
 	timeline := &timelineDB{conn: conn}
 	tombstone := &tombstoneDB{conn: conn}
 
diff --git a/internal/db/bundb/emoji.go b/internal/db/bundb/emoji.go
index 51d767a7b..81374ce78 100644
--- a/internal/db/bundb/emoji.go
+++ b/internal/db/bundb/emoji.go
@@ -32,14 +32,22 @@ import (
 )
 
 type emojiDB struct {
-	conn  *DBConn
-	cache *cache.EmojiCache
+	conn          *DBConn
+	emojiCache    *cache.EmojiCache
+	categoryCache *cache.EmojiCategoryCache
 }
 
 func (e *emojiDB) newEmojiQ(emoji *gtsmodel.Emoji) *bun.SelectQuery {
 	return e.conn.
 		NewSelect().
-		Model(emoji)
+		Model(emoji).
+		Relation("Category")
+}
+
+func (e *emojiDB) newEmojiCategoryQ(emojiCategory *gtsmodel.EmojiCategory) *bun.SelectQuery {
+	return e.conn.
+		NewSelect().
+		Model(emojiCategory)
 }
 
 func (e *emojiDB) PutEmoji(ctx context.Context, emoji *gtsmodel.Emoji) db.Error {
@@ -47,7 +55,7 @@ func (e *emojiDB) PutEmoji(ctx context.Context, emoji *gtsmodel.Emoji) db.Error
 		return e.conn.ProcessError(err)
 	}
 
-	e.cache.Put(emoji)
+	e.emojiCache.Put(emoji)
 	return nil
 }
 
@@ -64,7 +72,7 @@ func (e *emojiDB) UpdateEmoji(ctx context.Context, emoji *gtsmodel.Emoji, column
 		return nil, e.conn.ProcessError(err)
 	}
 
-	e.cache.Invalidate(emoji.ID)
+	e.emojiCache.Invalidate(emoji.ID)
 	return emoji, nil
 }
 
@@ -101,7 +109,7 @@ func (e *emojiDB) DeleteEmojiByID(ctx context.Context, id string) db.Error {
 		return err
 	}
 
-	e.cache.Invalidate(id)
+	e.emojiCache.Invalidate(id)
 	return nil
 }
 
@@ -245,7 +253,7 @@ func (e *emojiDB) GetEmojiByID(ctx context.Context, id string) (*gtsmodel.Emoji,
 	return e.getEmoji(
 		ctx,
 		func() (*gtsmodel.Emoji, bool) {
-			return e.cache.GetByID(id)
+			return e.emojiCache.GetByID(id)
 		},
 		func(emoji *gtsmodel.Emoji) error {
 			return e.newEmojiQ(emoji).Where("? = ?", bun.Ident("emoji.id"), id).Scan(ctx)
@@ -257,7 +265,7 @@ func (e *emojiDB) GetEmojiByURI(ctx context.Context, uri string) (*gtsmodel.Emoj
 	return e.getEmoji(
 		ctx,
 		func() (*gtsmodel.Emoji, bool) {
-			return e.cache.GetByURI(uri)
+			return e.emojiCache.GetByURI(uri)
 		},
 		func(emoji *gtsmodel.Emoji) error {
 			return e.newEmojiQ(emoji).Where("? = ?", bun.Ident("emoji.uri"), uri).Scan(ctx)
@@ -269,7 +277,7 @@ func (e *emojiDB) GetEmojiByShortcodeDomain(ctx context.Context, shortcode strin
 	return e.getEmoji(
 		ctx,
 		func() (*gtsmodel.Emoji, bool) {
-			return e.cache.GetByShortcodeDomain(shortcode, domain)
+			return e.emojiCache.GetByShortcodeDomain(shortcode, domain)
 		},
 		func(emoji *gtsmodel.Emoji) error {
 			q := e.newEmojiQ(emoji)
@@ -291,7 +299,7 @@ func (e *emojiDB) GetEmojiByStaticURL(ctx context.Context, imageStaticURL string
 	return e.getEmoji(
 		ctx,
 		func() (*gtsmodel.Emoji, bool) {
-			return e.cache.GetByImageStaticURL(imageStaticURL)
+			return e.emojiCache.GetByImageStaticURL(imageStaticURL)
 		},
 		func(emoji *gtsmodel.Emoji) error {
 			return e.
@@ -302,6 +310,55 @@ func (e *emojiDB) GetEmojiByStaticURL(ctx context.Context, imageStaticURL string
 	)
 }
 
+func (e *emojiDB) PutEmojiCategory(ctx context.Context, emojiCategory *gtsmodel.EmojiCategory) db.Error {
+	if _, err := e.conn.NewInsert().Model(emojiCategory).Exec(ctx); err != nil {
+		return e.conn.ProcessError(err)
+	}
+
+	e.categoryCache.Put(emojiCategory)
+	return nil
+}
+
+func (e *emojiDB) GetEmojiCategories(ctx context.Context) ([]*gtsmodel.EmojiCategory, db.Error) {
+	emojiCategoryIDs := []string{}
+
+	q := e.conn.
+		NewSelect().
+		TableExpr("? AS ?", bun.Ident("emoji_categories"), bun.Ident("emoji_category")).
+		Column("emoji_category.id").
+		Order("emoji_category.name ASC")
+
+	if err := q.Scan(ctx, &emojiCategoryIDs); err != nil {
+		return nil, e.conn.ProcessError(err)
+	}
+
+	return e.emojiCategoriesFromIDs(ctx, emojiCategoryIDs)
+}
+
+func (e *emojiDB) GetEmojiCategory(ctx context.Context, id string) (*gtsmodel.EmojiCategory, db.Error) {
+	return e.getEmojiCategory(
+		ctx,
+		func() (*gtsmodel.EmojiCategory, bool) {
+			return e.categoryCache.GetByID(id)
+		},
+		func(emojiCategory *gtsmodel.EmojiCategory) error {
+			return e.newEmojiCategoryQ(emojiCategory).Where("? = ?", bun.Ident("emoji_category.id"), id).Scan(ctx)
+		},
+	)
+}
+
+func (e *emojiDB) GetEmojiCategoryByName(ctx context.Context, name string) (*gtsmodel.EmojiCategory, db.Error) {
+	return e.getEmojiCategory(
+		ctx,
+		func() (*gtsmodel.EmojiCategory, bool) {
+			return e.categoryCache.GetByName(name)
+		},
+		func(emojiCategory *gtsmodel.EmojiCategory) error {
+			return e.newEmojiCategoryQ(emojiCategory).Where("LOWER(?) = ?", bun.Ident("emoji_category.name"), strings.ToLower(name)).Scan(ctx)
+		},
+	)
+}
+
 func (e *emojiDB) getEmoji(ctx context.Context, cacheGet func() (*gtsmodel.Emoji, bool), dbQuery func(*gtsmodel.Emoji) error) (*gtsmodel.Emoji, db.Error) {
 	// Attempt to fetch cached emoji
 	emoji, cached := cacheGet()
@@ -316,7 +373,7 @@ func (e *emojiDB) getEmoji(ctx context.Context, cacheGet func() (*gtsmodel.Emoji
 		}
 
 		// Place in the cache
-		e.cache.Put(emoji)
+		e.emojiCache.Put(emoji)
 	}
 
 	return emoji, nil
@@ -341,3 +398,43 @@ func (e *emojiDB) emojisFromIDs(ctx context.Context, emojiIDs []string) ([]*gtsm
 
 	return emojis, nil
 }
+
+func (e *emojiDB) getEmojiCategory(ctx context.Context, cacheGet func() (*gtsmodel.EmojiCategory, bool), dbQuery func(*gtsmodel.EmojiCategory) error) (*gtsmodel.EmojiCategory, db.Error) {
+	// Attempt to fetch cached emoji categories
+	emojiCategory, cached := cacheGet()
+
+	if !cached {
+		emojiCategory = &gtsmodel.EmojiCategory{}
+
+		// Not cached! Perform database query
+		err := dbQuery(emojiCategory)
+		if err != nil {
+			return nil, e.conn.ProcessError(err)
+		}
+
+		// Place in the cache
+		e.categoryCache.Put(emojiCategory)
+	}
+
+	return emojiCategory, nil
+}
+
+func (e *emojiDB) emojiCategoriesFromIDs(ctx context.Context, emojiCategoryIDs []string) ([]*gtsmodel.EmojiCategory, db.Error) {
+	// Catch case of no emoji categories early
+	if len(emojiCategoryIDs) == 0 {
+		return nil, db.ErrNoEntries
+	}
+
+	emojiCategories := make([]*gtsmodel.EmojiCategory, 0, len(emojiCategoryIDs))
+
+	for _, id := range emojiCategoryIDs {
+		emojiCategory, err := e.GetEmojiCategory(ctx, id)
+		if err != nil {
+			log.Errorf("emojiCategoriesFromIDs: error getting emoji category %q: %v", id, err)
+		}
+
+		emojiCategories = append(emojiCategories, emojiCategory)
+	}
+
+	return emojiCategories, nil
+}
diff --git a/internal/db/bundb/emoji_test.go b/internal/db/bundb/emoji_test.go
index b542f9b67..786d41e5d 100644
--- a/internal/db/bundb/emoji_test.go
+++ b/internal/db/bundb/emoji_test.go
@@ -24,6 +24,7 @@ import (
 
 	"github.com/stretchr/testify/suite"
 	"github.com/superseriousbusiness/gotosocial/internal/db"
+	"github.com/superseriousbusiness/gotosocial/testrig"
 )
 
 type EmojiTestSuite struct {
@@ -54,6 +55,8 @@ func (suite *EmojiTestSuite) TestGetEmojiByStaticURL() {
 	suite.NoError(err)
 	suite.NotNil(emoji)
 	suite.Equal("rainbow", emoji.Shortcode)
+	suite.NotNil(emoji.Category)
+	suite.Equal("reactions", emoji.Category.Name)
 }
 
 func (suite *EmojiTestSuite) TestGetAllEmojis() {
@@ -143,6 +146,21 @@ func (suite *EmojiTestSuite) TestGetSpecificEmojisFromDomain2() {
 	suite.Equal("yell", emojis[0].Shortcode)
 }
 
+func (suite *EmojiTestSuite) TestGetEmojiCategories() {
+	categories, err := suite.db.GetEmojiCategories(context.Background())
+	suite.NoError(err)
+	suite.Len(categories, 2)
+	// check alphabetical order
+	suite.Equal(categories[0].Name, "cute stuff")
+	suite.Equal(categories[1].Name, "reactions")
+}
+
+func (suite *EmojiTestSuite) TestGetEmojiCategory() {
+	category, err := suite.db.GetEmojiCategory(context.Background(), testrig.NewTestEmojiCategories()["reactions"].ID)
+	suite.NoError(err)
+	suite.NotNil(category)
+}
+
 func TestEmojiTestSuite(t *testing.T) {
 	suite.Run(t, new(EmojiTestSuite))
 }
diff --git a/internal/db/bundb/migrations/20221031145649_emoji_categories.go b/internal/db/bundb/migrations/20221031145649_emoji_categories.go
new file mode 100644
index 000000000..02e4a1f3a
--- /dev/null
+++ b/internal/db/bundb/migrations/20221031145649_emoji_categories.go
@@ -0,0 +1,46 @@
+/*
+   GoToSocial
+   Copyright (C) 2021-2022 GoToSocial Authors admin@gotosocial.org
+
+   This program is free software: you can redistribute it and/or modify
+   it under the terms of the GNU Affero General Public License as published by
+   the Free Software Foundation, either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU Affero General Public License for more details.
+
+   You should have received a copy of the GNU Affero General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+package migrations
+
+import (
+	"context"
+
+	gtsmodel "github.com/superseriousbusiness/gotosocial/internal/gtsmodel"
+	"github.com/uptrace/bun"
+)
+
+func init() {
+	up := func(ctx context.Context, db *bun.DB) error {
+		if _, err := db.NewCreateTable().Model(&gtsmodel.EmojiCategory{}).IfNotExists().Exec(ctx); err != nil {
+			return err
+		}
+
+		return nil
+	}
+
+	down := func(ctx context.Context, db *bun.DB) error {
+		return db.RunInTx(ctx, nil, func(ctx context.Context, tx bun.Tx) error {
+			return nil
+		})
+	}
+
+	if err := Migrations.Register(up, down); err != nil {
+		panic(err)
+	}
+}
diff --git a/internal/db/emoji.go b/internal/db/emoji.go
index d2f66a377..267213b2d 100644
--- a/internal/db/emoji.go
+++ b/internal/db/emoji.go
@@ -50,4 +50,12 @@ type Emoji interface {
 	GetEmojiByURI(ctx context.Context, uri string) (*gtsmodel.Emoji, Error)
 	// GetEmojiByStaticURL gets an emoji using the URL of the static version of the emoji image.
 	GetEmojiByStaticURL(ctx context.Context, imageStaticURL string) (*gtsmodel.Emoji, Error)
+	// PutEmojiCategory puts one new emoji category in the database.
+	PutEmojiCategory(ctx context.Context, emojiCategory *gtsmodel.EmojiCategory) Error
+	// GetEmojiCategories gets a slice of the names of all existing emoji categories.
+	GetEmojiCategories(ctx context.Context) ([]*gtsmodel.EmojiCategory, Error)
+	// GetEmojiCategory gets one emoji category by its id.
+	GetEmojiCategory(ctx context.Context, id string) (*gtsmodel.EmojiCategory, Error)
+	// GetEmojiCategoryByName gets one emoji category by its name.
+	GetEmojiCategoryByName(ctx context.Context, name string) (*gtsmodel.EmojiCategory, Error)
 }