feat: Implement Multi-Currency Revaluation Engine & FX Gain/Loss T

models/FXRevaluation.js

@@ -0,0 +1,142 @@
+const mongoose = require('mongoose');
+
+/**
+ * FXRevaluation Model
+ * Tracks foreign exchange revaluation history for compliance and audit
+ */
+const revaluationItemSchema = new mongoose.Schema({
+    accountId: {
+        type: mongoose.Schema.Types.ObjectId,
+        refPath: 'accountType'
+    },
+    accountType: {
+        type: String,
+        enum: ['Account', 'DebtAccount', 'TreasuryVault']
+    },
+    accountName: String,
+    currency: {
+        type: String,
+        required: true
+    },
+    originalAmount: {
+        type: Number,
+        required: true
+    },
+    originalRate: {
+        type: Number,
+        required: true
+    },
+    newRate: {
+        type: Number,
+        required: true
+    },
+    baseAmount: {
+        type: Number,
+        required: true
+    },
+    revaluedAmount: {
+        type: Number,
+        required: true
+    },
+    gainLoss: {
+        type: Number,
+        required: true
+    },
+    gainLossType: {
+        type: String,
+        enum: ['gain', 'loss'],
+        required: true
+    }
+}, { _id: false });
+
+const fxRevaluationSchema = new mongoose.Schema({
+    userId: {
+        type: mongoose.Schema.Types.ObjectId,
+        ref: 'User',
+        required: true,
+        index: true
+    },
+    revaluationId: {
+        type: String,
+        unique: true,
+        required: true
+    },
+    revaluationDate: {
+        type: Date,
+        required: true,
+        default: Date.now
+    },
+    baseCurrency: {
+        type: String,
+        required: true,
+        default: 'INR'
+    },
+    revaluationType: {
+        type: String,
+        enum: ['manual', 'automated', 'scheduled'],
+        default: 'automated'
+    },
+    items: [revaluationItemSchema],
+    summary: {
+        totalAccounts: {
+            type: Number,
+            default: 0
+        },
+        totalGain: {
+            type: Number,
+            default: 0
+        },
+        totalLoss: {
+            type: Number,
+            default: 0
+        },
+        netGainLoss: {
+            type: Number,
+            default: 0
+        },
+        currenciesRevalued: [String]
+    },
+    exchangeRates: [{
+        currency: String,
+        rate: Number,
+        source: String,
+        timestamp: Date
+    }],
+    journalEntryId: {
+        type: mongoose.Schema.Types.ObjectId,
+        ref: 'Transaction'
+    },
+    status: {
+        type: String,
+        enum: ['pending', 'completed', 'failed', 'reversed'],
+        default: 'pending'
+    },
+    performedBy: {
+        type: mongoose.Schema.Types.ObjectId,
+        ref: 'User'
+    },
+    notes: String
+}, {
+    timestamps: true
+});
+
+// Pre-save hook to calculate summary
+fxRevaluationSchema.pre('save', function (next) {
+    this.summary.totalAccounts = this.items.length;
+    this.summary.totalGain = this.items
+        .filter(i => i.gainLossType === 'gain')
+        .reduce((sum, i) => sum + Math.abs(i.gainLoss), 0);
+    this.summary.totalLoss = this.items
+        .filter(i => i.gainLossType === 'loss')
+        .reduce((sum, i) => sum + Math.abs(i.gainLoss), 0);
+    this.summary.netGainLoss = this.summary.totalGain - this.summary.totalLoss;
+    this.summary.currenciesRevalued = [...new Set(this.items.map(i => i.currency))];
+
+    next();
+});
+
+// Indexes
+fxRevaluationSchema.index({ userId: 1, revaluationDate: -1 });
+fxRevaluationSchema.index({ status: 1, revaluationType: 1 });
+
+module.exports = mongoose.model('FXRevaluation', fxRevaluationSchema);