优化目录结构

backend/src/main/java/com/openisle/model/Activity.java

@@ -0,0 +1,50 @@
+package com.openisle.model;
+
+import jakarta.persistence.*;
+import lombok.Getter;
+import lombok.NoArgsConstructor;
+import lombok.Setter;
+import org.hibernate.annotations.CreationTimestamp;
+
+import java.time.LocalDateTime;
+import java.util.HashSet;
+import java.util.Set;
+
+/** Generic activity entity. */
+@Entity
+@Getter
+@Setter
+@NoArgsConstructor
+@Table(name = "activities")
+public class Activity {
+    @Id
+    @GeneratedValue(strategy = GenerationType.IDENTITY)
+    private Long id;
+
+    @Column(nullable = false)
+    private String title;
+
+    private String icon;
+
+    private String content;
+
+    @Column(name = "start_time", nullable = false)
+    @CreationTimestamp
+    private LocalDateTime startTime;
+
+    @Column(name = "end_time")
+    private LocalDateTime endTime;
+
+    @Enumerated(EnumType.STRING)
+    @Column(nullable = false)
+    private ActivityType type = ActivityType.NORMAL;
+
+    @ManyToMany(fetch = FetchType.LAZY)
+    @JoinTable(name = "activity_participants",
+            joinColumns = @JoinColumn(name = "activity_id"),
+            inverseJoinColumns = @JoinColumn(name = "user_id"))
+    private Set<User> participants = new HashSet<>();
+
+    @Column(nullable = false)
+    private boolean ended = false;
+}

backend/src/main/java/com/openisle/model/ActivityType.java

@@ -0,0 +1,7 @@
+package com.openisle.model;
+
+/** Activity type enumeration. */
+public enum ActivityType {
+    NORMAL,
+    MILK_TEA
+}

backend/src/main/java/com/openisle/model/AiFormatUsage.java

@@ -0,0 +1,31 @@
+package com.openisle.model;
+
+import jakarta.persistence.*;
+import lombok.Getter;
+import lombok.NoArgsConstructor;
+import lombok.Setter;
+
+import java.time.LocalDate;
+
+/** Daily count of AI markdown formatting usage for a user. */
+@Entity
+@Getter
+@Setter
+@NoArgsConstructor
+@Table(name = "ai_format_usage",
+       uniqueConstraints = @UniqueConstraint(columnNames = {"user_id", "use_date"}))
+public class AiFormatUsage {
+    @Id
+    @GeneratedValue(strategy = GenerationType.IDENTITY)
+    private Long id;
+
+    @ManyToOne(fetch = FetchType.LAZY, optional = false)
+    @JoinColumn(name = "user_id")
+    private User user;
+
+    @Column(name = "use_date", nullable = false)
+    private LocalDate useDate;
+
+    @Column(nullable = false)
+    private int count;
+}

backend/src/main/java/com/openisle/model/Category.java

@@ -0,0 +1,29 @@
+package com.openisle.model;
+
+import jakarta.persistence.*;
+import lombok.Getter;
+import lombok.NoArgsConstructor;
+import lombok.Setter;
+
+@Entity
+@Getter
+@Setter
+@NoArgsConstructor
+@Table(name = "categories")
+public class Category {
+    @Id
+    @GeneratedValue(strategy = GenerationType.IDENTITY)
+    private Long id;
+
+    @Column(nullable = false, unique = true)
+    private String name;
+
+    @Column(nullable = false)
+    private String icon;
+
+    @Column
+    private String smallIcon;
+
+    @Column(name = "description", nullable = false)
+    private String description;
+}

backend/src/main/java/com/openisle/model/Comment.java

@@ -0,0 +1,41 @@
+package com.openisle.model;
+
+import jakarta.persistence.*;
+import lombok.Getter;
+import lombok.NoArgsConstructor;
+import lombok.Setter;
+import org.hibernate.annotations.CreationTimestamp;
+
+import java.time.LocalDateTime;
+
+@Entity
+@Getter
+@Setter
+@NoArgsConstructor
+@Table(name = "comments")
+public class Comment {
+    @Id
+    @GeneratedValue(strategy = GenerationType.IDENTITY)
+    private Long id;
+
+    @Column(nullable = false, columnDefinition = "TEXT")
+    private String content;
+
+    @CreationTimestamp
+    @Column(nullable = false, updatable = false,
+            columnDefinition = "DATETIME(6) DEFAULT CURRENT_TIMESTAMP(6)")
+    private LocalDateTime createdAt;
+
+    @ManyToOne(fetch = FetchType.LAZY, optional = false)
+    @JoinColumn(name = "author_id")
+    private User author;
+
+    @ManyToOne(fetch = FetchType.LAZY, optional = false)
+    @JoinColumn(name = "post_id")
+    private Post post;
+
+    @ManyToOne(fetch = FetchType.LAZY)
+    @JoinColumn(name = "parent_id")
+    private Comment parent;
+
+}

backend/src/main/java/com/openisle/model/CommentSort.java

@@ -0,0 +1,10 @@
+package com.openisle.model;
+
+/**
+ * Sort options for comments.
+ */
+public enum CommentSort {
+    NEWEST,
+    OLDEST,
+    MOST_INTERACTIONS
+}

backend/src/main/java/com/openisle/model/CommentSubscription.java

@@ -0,0 +1,27 @@
+package com.openisle.model;
+
+import jakarta.persistence.*;
+import lombok.Getter;
+import lombok.NoArgsConstructor;
+import lombok.Setter;
+
+/** Subscription to a comment for replies notifications. */
+@Entity
+@Getter
+@Setter
+@NoArgsConstructor
+@Table(name = "comment_subscriptions",
+       uniqueConstraints = @UniqueConstraint(columnNames = {"user_id", "comment_id"}))
+public class CommentSubscription {
+    @Id
+    @GeneratedValue(strategy = GenerationType.IDENTITY)
+    private Long id;
+
+    @ManyToOne(fetch = FetchType.LAZY, optional = false)
+    @JoinColumn(name = "user_id")
+    private User user;
+
+    @ManyToOne(fetch = FetchType.LAZY, optional = false)
+    @JoinColumn(name = "comment_id")
+    private Comment comment;
+}

backend/src/main/java/com/openisle/model/Draft.java

@@ -0,0 +1,41 @@
+package com.openisle.model;
+
+import jakarta.persistence.*;
+import lombok.Getter;
+import lombok.NoArgsConstructor;
+import lombok.Setter;
+
+import java.util.HashSet;
+import java.util.Set;
+
+@Entity
+@Getter
+@Setter
+@NoArgsConstructor
+@Table(name = "drafts", uniqueConstraints = {
+        @UniqueConstraint(columnNames = {"author_id"})
+})
+public class Draft {
+    @Id
+    @GeneratedValue(strategy = GenerationType.IDENTITY)
+    private Long id;
+
+    private String title;
+
+    @Column(columnDefinition = "TEXT")
+    private String content;
+
+    @ManyToOne(fetch = FetchType.LAZY, optional = false)
+    @JoinColumn(name = "author_id")
+    private User author;
+
+    @ManyToOne(fetch = FetchType.LAZY)
+    @JoinColumn(name = "category_id")
+    private Category category;
+
+    @ManyToMany(fetch = FetchType.LAZY)
+    @JoinTable(name = "draft_tags",
+            joinColumns = @JoinColumn(name = "draft_id"),
+            inverseJoinColumns = @JoinColumn(name = "tag_id"))
+    private Set<Tag> tags = new HashSet<>();
+}

backend/src/main/java/com/openisle/model/ExperienceLog.java

@@ -0,0 +1,37 @@
+package com.openisle.model;
+
+import jakarta.persistence.*;
+import lombok.Getter;
+import lombok.NoArgsConstructor;
+import lombok.Setter;
+
+import java.time.LocalDate;
+
+/** Daily experience gain counts for a user. */
+@Entity
+@Getter
+@Setter
+@NoArgsConstructor
+@Table(name = "experience_logs",
+       uniqueConstraints = @UniqueConstraint(columnNames = {"user_id", "log_date"}))
+public class ExperienceLog {
+    @Id
+    @GeneratedValue(strategy = GenerationType.IDENTITY)
+    private Long id;
+
+    @ManyToOne(fetch = FetchType.LAZY, optional = false)
+    @JoinColumn(name = "user_id")
+    private User user;
+
+    @Column(name = "log_date", nullable = false)
+    private LocalDate logDate;
+
+    @Column(name = "post_count", nullable = false)
+    private int postCount;
+
+    @Column(name = "comment_count", nullable = false)
+    private int commentCount;
+
+    @Column(name = "reaction_count", nullable = false)
+    private int reactionCount;
+}

backend/src/main/java/com/openisle/model/Image.java

@@ -0,0 +1,26 @@
+package com.openisle.model;
+
+import jakarta.persistence.*;
+import lombok.Getter;
+import lombok.NoArgsConstructor;
+import lombok.Setter;
+
+/**
+ * Image entity tracking COS image reference counts.
+ */
+@Entity
+@Getter
+@Setter
+@NoArgsConstructor
+@Table(name = "images")
+public class Image {
+    @Id
+    @GeneratedValue(strategy = GenerationType.IDENTITY)
+    private Long id;
+
+    @Column(nullable = false, unique = true, length = 512)
+    private String url;
+
+    @Column(nullable = false)
+    private long refCount = 0;
+}

backend/src/main/java/com/openisle/model/Notification.java

@@ -0,0 +1,61 @@
+package com.openisle.model;
+
+import jakarta.persistence.*;
+import lombok.Getter;
+import lombok.NoArgsConstructor;
+import lombok.Setter;
+import org.hibernate.annotations.CreationTimestamp;
+
+import java.time.LocalDateTime;
+
+/**
+ * Entity representing a user notification.
+ */
+@Entity
+@Getter
+@Setter
+@NoArgsConstructor
+@Table(name = "notifications")
+public class Notification {
+    @Id
+    @GeneratedValue(strategy = GenerationType.IDENTITY)
+    private Long id;
+
+    @Enumerated(EnumType.STRING)
+    @Column(nullable = false)
+    private NotificationType type;
+
+    @ManyToOne(fetch = FetchType.LAZY, optional = false)
+    @JoinColumn(name = "user_id")
+    private User user;
+
+    @ManyToOne(fetch = FetchType.LAZY)
+    @JoinColumn(name = "post_id")
+    private Post post;
+
+    @ManyToOne(fetch = FetchType.LAZY)
+    @JoinColumn(name = "comment_id")
+    private Comment comment;
+
+    @ManyToOne(fetch = FetchType.LAZY)
+    @JoinColumn(name = "from_user_id")
+    private User fromUser;
+
+    @Enumerated(EnumType.STRING)
+    @Column(name = "reaction_type")
+    private ReactionType reactionType;
+
+    @Column(length = 1000)
+    private String content;
+
+    @Column
+    private Boolean approved;
+
+    @Column(name = "is_read", nullable = false)
+    private boolean read = false;
+
+    @CreationTimestamp
+    @Column(nullable = false, updatable = false,
+            columnDefinition = "DATETIME(6) DEFAULT CURRENT_TIMESTAMP(6)")
+    private LocalDateTime createdAt;
+}

backend/src/main/java/com/openisle/model/NotificationType.java

@@ -0,0 +1,37 @@
+package com.openisle.model;
+
+/**
+ * Types of user notifications.
+ */
+public enum NotificationType {
+    /** Someone viewed your post */
+    POST_VIEWED,
+    /** Someone replied to your post or comment */
+    COMMENT_REPLY,
+    /** Someone reacted to your post or comment */
+    REACTION,
+    /** A new post is waiting for review */
+    POST_REVIEW_REQUEST,
+    /** Your post under review was approved or rejected */
+    POST_REVIEWED,
+    /** A subscribed post received a new comment */
+    POST_UPDATED,
+    /** Someone subscribed to your post */
+    POST_SUBSCRIBED,
+    /** Someone unsubscribed from your post */
+    POST_UNSUBSCRIBED,
+    /** Someone you follow published a new post */
+    FOLLOWED_POST,
+    /** Someone started following you */
+    USER_FOLLOWED,
+    /** Someone unfollowed you */
+    USER_UNFOLLOWED,
+    /** A user you subscribe to created a post or comment */
+    USER_ACTIVITY,
+    /** A user requested registration approval */
+    REGISTER_REQUEST,
+    /** A user redeemed an activity reward */
+    ACTIVITY_REDEEM,
+    /** You were mentioned in a post or comment */
+    MENTION
+}

backend/src/main/java/com/openisle/model/PasswordStrength.java

@@ -0,0 +1,7 @@
+package com.openisle.model;
+
+public enum PasswordStrength {
+    LOW,
+    MEDIUM,
+    HIGH
+}

backend/src/main/java/com/openisle/model/Post.java

@@ -0,0 +1,65 @@
+package com.openisle.model;
+
+import jakarta.persistence.*;
+import lombok.Getter;
+import lombok.NoArgsConstructor;
+import lombok.Setter;
+import org.hibernate.annotations.CreationTimestamp;
+
+import java.util.HashSet;
+import java.util.Set;
+
+import com.openisle.model.Tag;
+
+
+import java.time.LocalDateTime;
+
+/**
+ * Post entity representing an article posted by a user.
+ */
+@Entity
+@Getter
+@Setter
+@NoArgsConstructor
+@Table(name = "posts")
+public class Post {
+    @Id
+    @GeneratedValue(strategy = GenerationType.IDENTITY)
+    private Long id;
+
+    @Column(nullable = false)
+    private String title;
+
+    @Column(nullable = false, columnDefinition = "TEXT")
+    private String content;
+
+    @CreationTimestamp
+    @Column(nullable = false, updatable = false,
+            columnDefinition = "DATETIME(6) DEFAULT CURRENT_TIMESTAMP(6)")
+    private LocalDateTime createdAt;
+
+    @ManyToOne(optional = false, fetch = FetchType.LAZY)
+    @JoinColumn(name = "author_id")
+    private User author;
+
+    @ManyToOne(optional = false, fetch = FetchType.LAZY)
+    @JoinColumn(name = "category_id")
+    private Category category;
+
+    @ManyToMany(fetch = FetchType.LAZY)
+    @JoinTable(name = "post_tags",
+            joinColumns = @JoinColumn(name = "post_id"),
+            inverseJoinColumns = @JoinColumn(name = "tag_id"))
+    private java.util.Set<Tag> tags = new java.util.HashSet<>();
+
+    @Column(nullable = false)
+    private long views = 0;
+
+    @Enumerated(EnumType.STRING)
+    @Column(nullable = false)
+    private PostStatus status = PostStatus.PUBLISHED;
+
+    @Column
+    private LocalDateTime pinnedAt;
+
+}

backend/src/main/java/com/openisle/model/PostRead.java

@@ -0,0 +1,32 @@
+package com.openisle.model;
+
+import jakarta.persistence.*;
+import lombok.Getter;
+import lombok.NoArgsConstructor;
+import lombok.Setter;
+
+import java.time.LocalDateTime;
+
+/** Record of a user reading a post. */
+@Entity
+@Getter
+@Setter
+@NoArgsConstructor
+@Table(name = "post_reads",
+       uniqueConstraints = @UniqueConstraint(columnNames = {"user_id", "post_id"}))
+public class PostRead {
+    @Id
+    @GeneratedValue(strategy = GenerationType.IDENTITY)
+    private Long id;
+
+    @ManyToOne(fetch = FetchType.LAZY, optional = false)
+    @JoinColumn(name = "user_id")
+    private User user;
+
+    @ManyToOne(fetch = FetchType.LAZY, optional = false)
+    @JoinColumn(name = "post_id")
+    private Post post;
+
+    @Column(name = "last_read_at")
+    private LocalDateTime lastReadAt;
+}

backend/src/main/java/com/openisle/model/PostStatus.java

@@ -0,0 +1,10 @@
+package com.openisle.model;
+
+/**
+ * Status of a post during its lifecycle.
+ */
+public enum PostStatus {
+    PUBLISHED,
+    PENDING,
+    REJECTED
+}

backend/src/main/java/com/openisle/model/PostSubscription.java

@@ -0,0 +1,27 @@
+package com.openisle.model;
+
+import jakarta.persistence.*;
+import lombok.Getter;
+import lombok.NoArgsConstructor;
+import lombok.Setter;
+
+/** Subscription to a post for update notifications. */
+@Entity
+@Getter
+@Setter
+@NoArgsConstructor
+@Table(name = "post_subscriptions",
+       uniqueConstraints = @UniqueConstraint(columnNames = {"user_id", "post_id"}))
+public class PostSubscription {
+    @Id
+    @GeneratedValue(strategy = GenerationType.IDENTITY)
+    private Long id;
+
+    @ManyToOne(fetch = FetchType.LAZY, optional = false)
+    @JoinColumn(name = "user_id")
+    private User user;
+
+    @ManyToOne(fetch = FetchType.LAZY, optional = false)
+    @JoinColumn(name = "post_id")
+    private Post post;
+}

backend/src/main/java/com/openisle/model/PublishMode.java

@@ -0,0 +1,9 @@
+package com.openisle.model;
+
+/**
+ * Application-wide article publish mode.
+ */
+public enum PublishMode {
+    DIRECT,
+    REVIEW
+}

backend/src/main/java/com/openisle/model/PushSubscription.java

@@ -0,0 +1,40 @@
+package com.openisle.model;
+
+import jakarta.persistence.*;
+import lombok.Getter;
+import lombok.NoArgsConstructor;
+import lombok.Setter;
+import org.hibernate.annotations.CreationTimestamp;
+
+import java.time.LocalDateTime;
+
+/**
+ * Entity storing a browser push subscription for a user.
+ */
+@Entity
+@Getter
+@Setter
+@NoArgsConstructor
+@Table(name = "push_subscriptions")
+public class PushSubscription {
+    @Id
+    @GeneratedValue(strategy = GenerationType.IDENTITY)
+    private Long id;
+
+    @ManyToOne(fetch = FetchType.LAZY, optional = false)
+    @JoinColumn(name = "user_id")
+    private User user;
+
+    @Column(nullable = false, length = 512)
+    private String endpoint;
+
+    @Column(nullable = false, length = 256)
+    private String p256dh;
+
+    @Column(nullable = false, length = 256)
+    private String auth;
+
+    @CreationTimestamp
+    @Column(nullable = false, updatable = false)
+    private LocalDateTime createdAt;
+}

backend/src/main/java/com/openisle/model/Reaction.java

@@ -0,0 +1,46 @@
+package com.openisle.model;
+
+import jakarta.persistence.*;
+import lombok.Getter;
+import lombok.NoArgsConstructor;
+import lombok.Setter;
+import org.hibernate.annotations.CreationTimestamp;
+
+/**
+ * Reaction entity representing a user's reaction to a post or comment.
+ */
+@Entity
+@Getter
+@Setter
+@NoArgsConstructor
+@Table(name = "reactions",
+       uniqueConstraints = {
+           @UniqueConstraint(columnNames = {"user_id", "post_id", "type"}),
+           @UniqueConstraint(columnNames = {"user_id", "comment_id", "type"})
+       })
+public class Reaction {
+    @Id
+    @GeneratedValue(strategy = GenerationType.IDENTITY)
+    private Long id;
+
+    @Enumerated(EnumType.STRING)
+    @Column(nullable = false)
+    private ReactionType type;
+
+    @ManyToOne(fetch = FetchType.LAZY, optional = false)
+    @JoinColumn(name = "user_id")
+    private User user;
+
+    @ManyToOne(fetch = FetchType.LAZY)
+    @JoinColumn(name = "post_id")
+    private Post post;
+
+    @ManyToOne(fetch = FetchType.LAZY)
+    @JoinColumn(name = "comment_id")
+    private Comment comment;
+
+    @CreationTimestamp
+    @Column(nullable = false, updatable = false,
+            columnDefinition = "DATETIME(6) DEFAULT CURRENT_TIMESTAMP(6)")
+    private java.time.LocalDateTime createdAt;
+}

backend/src/main/java/com/openisle/model/ReactionType.java

@@ -0,0 +1,19 @@
+package com.openisle.model;
+
+/**
+ * Enum of possible reaction types for posts and comments.
+ */
+public enum ReactionType {
+    LIKE,
+    DISLIKE,
+    RECOMMEND,
+    ANGRY,
+    FLUSHED,
+    STAR_STRUCK,
+    ROFL,
+    HOLDING_BACK_TEARS,
+    MIND_BLOWN,
+    POOP,
+    CLOWN,
+    SKULL
+}

backend/src/main/java/com/openisle/model/RegisterMode.java

@@ -0,0 +1,9 @@
+package com.openisle.model;
+
+/**
+ * Application-wide user registration mode.
+ */
+public enum RegisterMode {
+    DIRECT,
+    WHITELIST
+}

backend/src/main/java/com/openisle/model/Role.java

@@ -0,0 +1,6 @@
+package com.openisle.model;
+
+public enum Role {
+    ADMIN,
+    USER
+}

backend/src/main/java/com/openisle/model/Tag.java

@@ -0,0 +1,45 @@
+package com.openisle.model;
+
+import jakarta.persistence.*;
+import lombok.Getter;
+import lombok.NoArgsConstructor;
+import lombok.Setter;
+import org.hibernate.annotations.CreationTimestamp;
+
+import java.time.LocalDateTime;
+
+
+@Entity
+@Getter
+@Setter
+@NoArgsConstructor
+@Table(name = "tags")
+public class Tag {
+    @Id
+    @GeneratedValue(strategy = GenerationType.IDENTITY)
+    private Long id;
+
+    @Column(nullable = false, unique = true)
+    private String name;
+
+    @Column
+    private String icon;
+
+    @Column
+    private String smallIcon;
+
+    @Column(name = "description", nullable = false)
+    private String description;
+
+    @Column(nullable = false)
+    private boolean approved = true;
+
+    @CreationTimestamp
+    @Column(nullable = false, updatable = false,
+            columnDefinition = "DATETIME(6) DEFAULT CURRENT_TIMESTAMP(6)")
+    private LocalDateTime createdAt;
+
+    @ManyToOne(fetch = FetchType.LAZY)
+    @JoinColumn(name = "creator_id")
+    private User creator;
+}

backend/src/main/java/com/openisle/model/User.java

@@ -0,0 +1,64 @@
+package com.openisle.model;
+
+import jakarta.persistence.*;
+import lombok.Getter;
+import lombok.NoArgsConstructor;
+import lombok.Setter;
+import org.hibernate.annotations.CreationTimestamp;
+import java.time.LocalDateTime;
+
+import com.openisle.model.Role;
+
+/**
+ * Simple user entity with basic fields and a role.
+ */
+
+@Entity
+@Getter
+@Setter
+@NoArgsConstructor
+@Table(name = "users")
+public class User {
+    @Id
+    @GeneratedValue(strategy = GenerationType.IDENTITY)
+    private Long id;
+
+    @Column(nullable = false, unique = true)
+    private String username;
+
+    @Column(nullable = false, unique = true)
+    private String email;
+
+    @Column(nullable = false)
+    private String password;
+
+    @Column(nullable = false)
+    private boolean verified = false;
+
+    private String verificationCode;
+
+    private String passwordResetCode;
+
+    private String avatar;
+
+    @Column(nullable = false)
+    private int experience = 0;
+
+    @Column(length = 1000)
+    private String introduction;
+
+    @Column(length = 1000)
+    private String registerReason;
+
+    @Column(nullable = false)
+    private boolean approved = true;
+
+    @Enumerated(EnumType.STRING)
+    @Column(nullable = false)
+    private Role role = Role.USER;
+
+    @CreationTimestamp
+    @Column(nullable = false, updatable = false,
+            columnDefinition = "DATETIME(6) DEFAULT CURRENT_TIMESTAMP(6)")
+    private LocalDateTime createdAt;
+}

backend/src/main/java/com/openisle/model/UserSubscription.java

@@ -0,0 +1,27 @@
+package com.openisle.model;
+
+import jakarta.persistence.*;
+import lombok.Getter;
+import lombok.NoArgsConstructor;
+import lombok.Setter;
+
+/** Following relationship between users. */
+@Entity
+@Getter
+@Setter
+@NoArgsConstructor
+@Table(name = "user_subscriptions",
+       uniqueConstraints = @UniqueConstraint(columnNames = {"subscriber_id", "target_id"}))
+public class UserSubscription {
+    @Id
+    @GeneratedValue(strategy = GenerationType.IDENTITY)
+    private Long id;
+
+    @ManyToOne(fetch = FetchType.LAZY, optional = false)
+    @JoinColumn(name = "subscriber_id")
+    private User subscriber;
+
+    @ManyToOne(fetch = FetchType.LAZY, optional = false)
+    @JoinColumn(name = "target_id")
+    private User target;
+}

backend/src/main/java/com/openisle/model/UserVisit.java

@@ -0,0 +1,28 @@
+package com.openisle.model;
+
+import jakarta.persistence.*;
+import lombok.Getter;
+import lombok.NoArgsConstructor;
+import lombok.Setter;
+
+import java.time.LocalDate;
+
+/** Daily visit record for a user. */
+@Entity
+@Getter
+@Setter
+@NoArgsConstructor
+@Table(name = "user_visits",
+       uniqueConstraints = @UniqueConstraint(columnNames = {"user_id", "visit_date"}))
+public class UserVisit {
+    @Id
+    @GeneratedValue(strategy = GenerationType.IDENTITY)
+    private Long id;
+
+    @ManyToOne(fetch = FetchType.LAZY, optional = false)
+    @JoinColumn(name = "user_id")
+    private User user;
+
+    @Column(name = "visit_date", nullable = false)
+    private LocalDate visitDate;
+}