add changes

backend/models/GuestSettings.js

@@ -0,0 +1,114 @@
+const { v4: uuidv4 } = require('uuid');
+
+module.exports = (sequelize, DataTypes) => {
+  const GuestSettings = sequelize.define('GuestSettings', {
+    id: {
+      type: DataTypes.CHAR(36),
+      primaryKey: true,
+      defaultValue: () => uuidv4(),
+      allowNull: false,
+      comment: 'UUID primary key'
+    },
+    maxQuizzes: {
+      type: DataTypes.INTEGER,
+      allowNull: false,
+      defaultValue: 3,
+      validate: {
+        min: {
+          args: [1],
+          msg: 'Maximum quizzes must be at least 1'
+        },
+        max: {
+          args: [50],
+          msg: 'Maximum quizzes cannot exceed 50'
+        }
+      },
+      field: 'max_quizzes',
+      comment: 'Maximum number of quizzes a guest can take'
+    },
+    expiryHours: {
+      type: DataTypes.INTEGER,
+      allowNull: false,
+      defaultValue: 24,
+      validate: {
+        min: {
+          args: [1],
+          msg: 'Expiry hours must be at least 1'
+        },
+        max: {
+          args: [168],
+          msg: 'Expiry hours cannot exceed 168 (7 days)'
+        }
+      },
+      field: 'expiry_hours',
+      comment: 'Guest session expiry time in hours'
+    },
+    publicCategories: {
+      type: DataTypes.JSON,
+      allowNull: false,
+      defaultValue: [],
+      get() {
+        const value = this.getDataValue('publicCategories');
+        if (typeof value === 'string') {
+          try {
+            return JSON.parse(value);
+          } catch (e) {
+            return [];
+          }
+        }
+        return value || [];
+      },
+      set(value) {
+        this.setDataValue('publicCategories', JSON.stringify(value));
+      },
+      field: 'public_categories',
+      comment: 'Array of category UUIDs accessible to guests'
+    },
+    featureRestrictions: {
+      type: DataTypes.JSON,
+      allowNull: false,
+      defaultValue: {
+        allowBookmarks: false,
+        allowReview: true,
+        allowPracticeMode: true,
+        allowTimedMode: false,
+        allowExamMode: false
+      },
+      get() {
+        const value = this.getDataValue('featureRestrictions');
+        if (typeof value === 'string') {
+          try {
+            return JSON.parse(value);
+          } catch (e) {
+            return {
+              allowBookmarks: false,
+              allowReview: true,
+              allowPracticeMode: true,
+              allowTimedMode: false,
+              allowExamMode: false
+            };
+          }
+        }
+        return value || {
+          allowBookmarks: false,
+          allowReview: true,
+          allowPracticeMode: true,
+          allowTimedMode: false,
+          allowExamMode: false
+        };
+      },
+      set(value) {
+        this.setDataValue('featureRestrictions', JSON.stringify(value));
+      },
+      field: 'feature_restrictions',
+      comment: 'Feature restrictions for guest users'
+    }
+  }, {
+    tableName: 'guest_settings',
+    timestamps: true,
+    underscored: true,
+    comment: 'System-wide guest user settings'
+  });
+
+  return GuestSettings;
+};

backend/models/QuizSession.js

@@ -164,6 +164,32 @@ module.exports = (sequelize) => {
     tableName: 'quiz_sessions',
     timestamps: true,
     underscored: true,
+    indexes: [
+      {
+        fields: ['user_id']
+      },
+      {
+        fields: ['guest_session_id']
+      },
+      {
+        fields: ['category_id']
+      },
+      {
+        fields: ['status']
+      },
+      {
+        fields: ['created_at']
+      },
+      {
+        fields: ['user_id', 'created_at']
+      },
+      {
+        fields: ['guest_session_id', 'created_at']
+      },
+      {
+        fields: ['category_id', 'status']
+      }
+    ],
     hooks: {
       beforeValidate: (session) => {
         // Generate UUID if not provided

backend/models/QuizSessionQuestion.js

@@ -32,6 +32,21 @@ module.exports = (sequelize) => {
     timestamps: true,
     createdAt: 'created_at',
     updatedAt: 'updated_at',
+    indexes: [
+      {
+        fields: ['quiz_session_id']
+      },
+      {
+        fields: ['question_id']
+      },
+      {
+        fields: ['quiz_session_id', 'question_order']
+      },
+      {
+        unique: true,
+        fields: ['quiz_session_id', 'question_id']
+      }
+    ],
     hooks: {
       beforeValidate: (quizSessionQuestion) => {
         if (!quizSessionQuestion.id) {

backend/models/UserBookmark.js

@@ -0,0 +1,96 @@
+/**
+ * UserBookmark Model
+ * Junction table for user-saved questions
+ */
+
+const { DataTypes } = require('sequelize');
+const { v4: uuidv4 } = require('uuid');
+
+module.exports = (sequelize) => {
+  const UserBookmark = sequelize.define('UserBookmark', {
+    id: {
+      type: DataTypes.UUID,
+      defaultValue: () => uuidv4(),
+      primaryKey: true,
+      allowNull: false,
+      comment: 'Primary key UUID'
+    },
+    userId: {
+      type: DataTypes.UUID,
+      allowNull: false,
+      references: {
+        model: 'users',
+        key: 'id'
+      },
+      onDelete: 'CASCADE',
+      comment: 'Reference to user who bookmarked'
+    },
+    questionId: {
+      type: DataTypes.UUID,
+      allowNull: false,
+      references: {
+        model: 'questions',
+        key: 'id'
+      },
+      onDelete: 'CASCADE',
+      comment: 'Reference to bookmarked question'
+    },
+    notes: {
+      type: DataTypes.TEXT,
+      allowNull: true,
+      comment: 'Optional notes about the bookmark'
+    },
+    createdAt: {
+      type: DataTypes.DATE,
+      allowNull: false,
+      defaultValue: DataTypes.NOW,
+      field: 'created_at',
+      comment: 'When the bookmark was created'
+    },
+    updatedAt: {
+      type: DataTypes.DATE,
+      allowNull: false,
+      defaultValue: DataTypes.NOW,
+      field: 'updated_at',
+      comment: 'When the bookmark was last updated'
+    }
+  }, {
+    tableName: 'user_bookmarks',
+    timestamps: true,
+    underscored: true,
+    indexes: [
+      {
+        unique: true,
+        fields: ['user_id', 'question_id'],
+        name: 'idx_user_question_unique'
+      },
+      {
+        fields: ['user_id'],
+        name: 'idx_user_bookmarks_user'
+      },
+      {
+        fields: ['question_id'],
+        name: 'idx_user_bookmarks_question'
+      },
+      {
+        fields: ['bookmarked_at'],
+        name: 'idx_user_bookmarks_date'
+      }
+    ]
+  });
+
+  // Define associations
+  UserBookmark.associate = function(models) {
+    UserBookmark.belongsTo(models.User, {
+      foreignKey: 'userId',
+      as: 'User'
+    });
+    
+    UserBookmark.belongsTo(models.Question, {
+      foreignKey: 'questionId',
+      as: 'Question'
+    });
+  };
+
+  return UserBookmark;
+};