import { tenantGuard } from "@/lib/server/tenantGuard";
import { Schema, model, models, Model, Types, Document } from "mongoose";

export interface IStockTransfer extends Document {
  _id: Types.ObjectId;
  businessId: Types.ObjectId;
  fromBranchId: Types.ObjectId;
  toBranchId: Types.ObjectId;
  productId: Types.ObjectId;
  quantity: number;
  clientUuid: string; // idempotency key from the form, so a double-submit moves stock once
  note: string | null;
  recordedBy: Types.ObjectId;
  createdAt: Date;
}

/**
 * An inter-branch stock transfer. The stock itself moves through two
 * StockMovement rows (TRANSFER_OUT at the source, TRANSFER_IN at the
 * destination) whose refId is this transfer's id.
 */
const stockTransferSchema = new Schema<IStockTransfer>(
  {
    businessId: { type: Schema.Types.ObjectId, ref: "Business", required: true },
    fromBranchId: { type: Schema.Types.ObjectId, ref: "Branch", required: true },
    toBranchId: { type: Schema.Types.ObjectId, ref: "Branch", required: true },
    productId: { type: Schema.Types.ObjectId, ref: "Product", required: true },
    quantity: { type: Number, required: true, min: 1 },
    clientUuid: { type: String, required: true },
    note: { type: String, default: null, trim: true },
    recordedBy: { type: Schema.Types.ObjectId, ref: "User", required: true },
  },
  { timestamps: { createdAt: true, updatedAt: false } }
);

stockTransferSchema.index({ businessId: 1, clientUuid: 1 }, { unique: true });
stockTransferSchema.index({ businessId: 1, createdAt: -1 });

stockTransferSchema.plugin(tenantGuard);

export const StockTransfer =
  (models.StockTransfer as Model<IStockTransfer>) ||
  model<IStockTransfer>("StockTransfer", stockTransferSchema);