feat: enhance limits

internal/model/admin.go

@@ -24,6 +24,13 @@ type AdminUser struct {
 	// Providers lists linked OAuth providers (e.g. "google", "facebook").
 	HasPassword bool     `json:"has_password"`
 	Providers   []string `json:"providers"`
+
+	// Effective save limits in force for this user (plan default merged with any
+	// admin override); -1 means unlimited. The admin UI pre-fills the "Edit
+	// limits" modal with these.
+	BookmarkLimit          int `json:"bookmark_limit"`
+	PublicCollectionLimit  int `json:"public_collection_limit"`
+	PrivateCollectionLimit int `json:"private_collection_limit"`
 }
 
 // AdminPost is a row in the admin posts table.

internal/model/limits.go

@@ -0,0 +1,51 @@
+package model
+
+// Plan-default save limits (-1 = unlimited). Per-user override columns on the
+// users row take precedence when non-nil; admins set them from the panel.
+const (
+	planPremium = "premium"
+
+	defaultFreeBookmarkLimit    = 1
+	defaultPremiumBookmarkLimit = 5
+	defaultFreeCollectionLimit  = 5 // per visibility; premium = unlimited
+)
+
+// UserLimits are the effective per-resource caps in force for a user (-1 means
+// unlimited). Surfaced on the self user payload so the app can render
+// "X / Y used" and gate create actions without hardcoding the numbers.
+type UserLimits struct {
+	Bookmarks          int `json:"bookmarks"`
+	PublicCollections  int `json:"public_collections"`
+	PrivateCollections int `json:"private_collections"`
+}
+
+// ResolveLimits computes the effective caps from a plan plus optional per-user
+// overrides (nil = use the plan default). Shared by the self payload and the
+// admin user listing so both agree on what's in force.
+func ResolveLimits(plan string, bookmark, publicCollection, privateCollection *int) UserLimits {
+	premium := plan == planPremium
+
+	bm := defaultFreeBookmarkLimit
+	if premium {
+		bm = defaultPremiumBookmarkLimit
+	}
+	pub, priv := defaultFreeCollectionLimit, defaultFreeCollectionLimit
+	if premium {
+		pub, priv = -1, -1
+	}
+	if bookmark != nil {
+		bm = *bookmark
+	}
+	if publicCollection != nil {
+		pub = *publicCollection
+	}
+	if privateCollection != nil {
+		priv = *privateCollection
+	}
+	return UserLimits{Bookmarks: bm, PublicCollections: pub, PrivateCollections: priv}
+}
+
+// EffectiveLimits resolves this user's caps (plan default + any overrides).
+func (u *User) EffectiveLimits() UserLimits {
+	return ResolveLimits(u.Plan, u.BookmarkLimit, u.PublicCollectionLimit, u.PrivateCollectionLimit)
+}

internal/model/user.go

@@ -75,6 +75,13 @@ type User struct {
 	// BannedAt suspends the account when set: RequireAuth rejects the session
 	// and LogIn refuses to issue a new one. nil = in good standing.
 	BannedAt *time.Time `json:"banned_at,omitempty"`
+
+	// Per-user save-limit overrides (admin-settable; nil = use the plan
+	// default). Never serialized raw — surfaced only via the derived `limits`
+	// object in MarshalJSON so the app can render/enforce the right caps.
+	BookmarkLimit          *int `json:"-"`
+	PublicCollectionLimit  *int `json:"-"`
+	PrivateCollectionLimit *int `json:"-"`
 }
 
 // MarshalJSON adds a derived `has_password` flag so the frontend can pick
@@ -84,10 +91,12 @@ func (u User) MarshalJSON() ([]byte, error) {
 	type alias User
 	return json.Marshal(&struct {
 		alias
-		HasPassword bool `json:"has_password"`
+		HasPassword bool       `json:"has_password"`
+		Limits      UserLimits `json:"limits"`
 	}{
 		alias:       alias(u),
 		HasPassword: u.PasswordHash != nil,
+		Limits:      u.EffectiveLimits(),
 	})
 }