feat: improve user schema validation and serialization

BACKEND/models/user.model.js

@@ -1,24 +1,28 @@
 import mongoose from "mongoose";
 
-const addressSchema = new mongoose.Schema({
-  label:      { type: String, trim: true, default: 'Home' },
-  fullName:   { type: String, trim: true, required: true },
-  phone:      { type: String, trim: true, default: '' },
-  line1:      { type: String, trim: true, required: true },
-  line2:      { type: String, trim: true, default: '' },
-  city:       { type: String, trim: true, required: true },
-  state:      { type: String, trim: true, default: '' },
-  postalCode: { type: String, trim: true, required: true },
-  country:    { type: String, trim: true, required: true },
-  isDefault:  { type: Boolean, default: false },
-}, { _id: true });
+const addressSchema = new mongoose.Schema(
+  {
+    label: { type: String, trim: true, default: "Home" },
+    fullName: { type: String, trim: true, required: true },
+    phone: { type: String, trim: true, default: "" },
+    line1: { type: String, trim: true, required: true },
+    line2: { type: String, trim: true, default: "" },
+    city: { type: String, trim: true, required: true },
+    state: { type: String, trim: true, default: "" },
+    postalCode: { type: String, trim: true, required: true },
+    country: { type: String, trim: true, required: true },
+    isDefault: { type: Boolean, default: false },
+  },
+  { _id: true }
+);
 
 const userSchema = new mongoose.Schema(
   {
     name: {
       type: String,
       required: [true, "Name is required"],
       trim: true,
+      maxlength: [50, "Name cannot exceed 50 characters"],
     },
 
     email: {
@@ -27,31 +31,39 @@ const userSchema = new mongoose.Schema(
       unique: true,
       lowercase: true,
       trim: true,
+      match: [
+        /^\w+([.-]?\w+)*@\w+([.-]?\w+)*(\.\w{2,3})+$/,
+        "Please enter a valid email address",
+      ],
     },
 
     password: {
       type: String,
       minlength: 6,
-      // Not required because OAuth users won't have a password initially
+      // Keeping it visible to avoid breaking login flow
     },
 
     googleId: {
       type: String,
+      unique: true,
+      sparse: true,
     },
 
     githubId: {
       type: String,
+      unique: true,
+      sparse: true,
     },
 
     phone: {
       type: String,
       trim: true,
-      default: '',
+      default: "",
     },
 
     avatar: {
       type: String,
-      default: '',
+      default: "",
     },
 
     addresses: {
@@ -61,8 +73,8 @@ const userSchema = new mongoose.Schema(
 
     provider: {
       type: String,
-      enum: ['local', 'google', 'github'],
-      default: 'local',
+      enum: ["local", "google", "github"],
+      default: "local",
     },
 
     resetPasswordToken: {
@@ -77,9 +89,18 @@ const userSchema = new mongoose.Schema(
   },
   {
     timestamps: true,
+    toJSON: {
+      transform: function (doc, ret) {
+        delete ret.password;
+        delete ret.resetPasswordToken;
+        delete ret.resetPasswordExpires;
+        delete ret.__v;
+        return ret;
+      },
+    },
   }
 );
 
 const User = mongoose.model("User", userSchema);
 
-export default User;
+export default User;