feat(api): add PATCH /users/@me/fields, finish POST /auth/discord/callback

backend/db/field.go

@@ -2,12 +2,21 @@ package db
 
 import (
 	"context"
+	"fmt"
 
 	"emperror.dev/errors"
 	"github.com/georgysavva/scany/pgxscan"
+	"github.com/jackc/pgx/v4"
 	"github.com/rs/xid"
 )
 
+const (
+	MaxFields           = 25
+	FieldNameMaxLength  = 100
+	FieldEntriesLimit   = 100
+	FieldEntryMaxLength = 50
+)
+
 type Field struct {
 	ID          int64    `json:"-"`
 	Name        string   `json:"name"`
@@ -18,6 +27,53 @@ type Field struct {
 	Avoid       []string `json:"avoid"`
 }
 
+// Validate validates this field. If it is invalid, a non-empty string is returned as error message.
+func (f Field) Validate() string {
+	if f.Name == "" {
+		return "name cannot be empty"
+	}
+
+	if length := len([]rune(f.Name)); length > FieldNameMaxLength {
+		return fmt.Sprintf("name max length is %d characters, length is %d", FieldNameMaxLength, length)
+	}
+
+	if length := len(f.Favourite) + len(f.Okay) + len(f.Jokingly) + len(f.FriendsOnly) + len(f.Avoid); length > FieldEntriesLimit {
+		return fmt.Sprintf("max number of entries is %d, current number is %d", FieldEntriesLimit, length)
+	}
+
+	for i, entry := range f.Favourite {
+		if length := len([]rune(entry)); length > FieldEntryMaxLength {
+			return fmt.Sprintf("favourite.%d: name max length is %d characters, length is %d", i, FieldEntryMaxLength, length)
+		}
+	}
+
+	for i, entry := range f.Okay {
+		if length := len([]rune(entry)); length > FieldEntryMaxLength {
+			return fmt.Sprintf("okay.%d: name max length is %d characters, length is %d", i, FieldEntryMaxLength, length)
+		}
+	}
+
+	for i, entry := range f.Jokingly {
+		if length := len([]rune(entry)); length > FieldEntryMaxLength {
+			return fmt.Sprintf("jokingly.%d: name max length is %d characters, length is %d", i, FieldEntryMaxLength, length)
+		}
+	}
+
+	for i, entry := range f.FriendsOnly {
+		if length := len([]rune(entry)); length > FieldEntryMaxLength {
+			return fmt.Sprintf("friends_only.%d: name max length is %d characters, length is %d", i, FieldEntryMaxLength, length)
+		}
+	}
+
+	for i, entry := range f.Avoid {
+		if length := len([]rune(entry)); length > FieldEntryMaxLength {
+			return fmt.Sprintf("avoid.%d: name max length is %d characters, length is %d", i, FieldEntryMaxLength, length)
+		}
+	}
+
+	return ""
+}
+
 // UserFields returns the fields associated with the given user ID.
 func (db *DB) UserFields(ctx context.Context, id xid.ID) (fs []Field, err error) {
 	sql, args, err := sq.
@@ -33,3 +89,45 @@ func (db *DB) UserFields(ctx context.Context, id xid.ID) (fs []Field, err error)
 	}
 	return fs, nil
 }
+
+// SetUserFields updates the fields for the given user.
+func (db *DB) SetUserFields(ctx context.Context, userID xid.ID, fields []Field) (err error) {
+	tx, err := db.Begin(ctx)
+	if err != nil {
+		return errors.Wrap(err, "building sql")
+	}
+	defer tx.Rollback(ctx)
+
+	sql, args, err := sq.Delete("user_fields").Where("user_id = ?", userID).ToSql()
+	if err != nil {
+		return errors.Wrap(err, "building sql")
+	}
+
+	_, err = tx.Exec(ctx, sql, args...)
+	if err != nil {
+		return errors.Wrap(err, "deleting existing fields")
+	}
+
+	_, err = tx.CopyFrom(ctx,
+		pgx.Identifier{"user_fields"},
+		[]string{"name", "favourite", "okay", "jokingly", "friends_only", "avoid"},
+		pgx.CopyFromSlice(len(fields), func(i int) ([]any, error) {
+			return []any{
+				fields[i].Name,
+				fields[i].Favourite,
+				fields[i].Okay,
+				fields[i].Jokingly,
+				fields[i].FriendsOnly,
+				fields[i].Avoid,
+			}, nil
+		}))
+	if err != nil {
+		return errors.Wrap(err, "inserting new fields")
+	}
+
+	err = tx.Commit(ctx)
+	if err != nil {
+		return errors.Wrap(err, "committing transaction")
+	}
+	return nil
+}