implement update train details feature: add DTO, service method, and UI modal for editing train name and run numbers

apps/edr-freight-api/src/modules/trains/dto/update-train-details.dto.ts

@@ -0,0 +1,29 @@
+import { ApiPropertyOptional } from '@nestjs/swagger';
+import { IsNotEmpty, IsOptional, IsString, MaxLength } from 'class-validator';
+
+/**
+ * Edit a built train's display identity: its name and its fixed import/export
+ * run numbers. Composition (yard, locomotives, wagons) has its own endpoints.
+ * Omitted fields keep their current value; an empty trainName clears the name.
+ */
+export class UpdateTrainDetailsDto {
+  @ApiPropertyOptional({ description: 'Display name; empty string clears it' })
+  @IsOptional()
+  @IsString()
+  @MaxLength(100)
+  trainName?: string;
+
+  @ApiPropertyOptional({ description: 'Fixed IMPORT (even) run number' })
+  @IsOptional()
+  @IsString()
+  @IsNotEmpty()
+  @MaxLength(20)
+  importTrainNumber?: string;
+
+  @ApiPropertyOptional({ description: 'Fixed EXPORT (odd) run number' })
+  @IsOptional()
+  @IsString()
+  @IsNotEmpty()
+  @MaxLength(20)
+  exportTrainNumber?: string;
+}

apps/edr-freight-api/src/modules/trains/entities/train.entity.ts

@@ -45,7 +45,7 @@ export class Train extends BaseEntity {
   trainNumber?: string;
 
   @Column({ name: 'train_name', type: 'varchar', length: 100, nullable: true })
-  trainName?: string;
+  trainName?: string | null;
 
   @Column({ name: 'route_id', type: 'uuid', nullable: true })
   routeId?: string;

apps/edr-freight-api/src/modules/trains/train-builder.controller.ts

@@ -19,6 +19,7 @@ import { AssignTrainWagonsDto } from './dto/assign-train-wagons.dto';
 import { BuildTrainDto } from './dto/build-train.dto';
 import { ListBuiltTrainsQueryDto } from './dto/list-built-trains-query.dto';
 import { ReorderTrainWagonsDto } from './dto/reorder-train-wagons.dto';
+import { UpdateTrainDetailsDto } from './dto/update-train-details.dto';
 import { UpdateTrainLocomotivesDto } from './dto/update-train-locomotives.dto';
 import { UpdateTrainYardDto } from './dto/update-train-yard.dto';
 import { TrainBuilderService } from './train-builder.service';
@@ -59,6 +60,18 @@ export class TrainBuilderController {
     return this.trainBuilderService.setLocomotives(id, dto);
   }
 
+  @Patch(':id/details')
+  @FleetManage()
+  @ApiOperation({
+    summary: "Edit the train's name and fixed import/export run numbers",
+  })
+  updateDetails(
+    @Param('id', ParseUUIDPipe) id: string,
+    @Body() dto: UpdateTrainDetailsDto,
+  ) {
+    return this.trainBuilderService.updateDetails(id, dto);
+  }
+
   @Patch(':id/yard')
   @FleetManage()
   @ApiOperation({

apps/edr-freight-api/src/modules/trains/train-builder.service.ts

@@ -17,6 +17,7 @@ import { AssignTrainWagonsDto } from './dto/assign-train-wagons.dto';
 import { BuildTrainDto } from './dto/build-train.dto';
 import { ListBuiltTrainsQueryDto } from './dto/list-built-trains-query.dto';
 import { ReorderTrainWagonsDto } from './dto/reorder-train-wagons.dto';
+import { UpdateTrainDetailsDto } from './dto/update-train-details.dto';
 import { UpdateTrainLocomotivesDto } from './dto/update-train-locomotives.dto';
 import { TrainLocomotive } from './entities/train-locomotive.entity';
 import { Train } from './entities/train.entity';
@@ -331,6 +332,53 @@ export class TrainBuilderService {
     return this.getComposition(id);
   }
 
+  /**
+   * Edit a built train's display identity: name and fixed import/export run
+   * numbers. Mirrors the build-time number rules — the pair may not collide
+   * with any other train's pair or legacy number (friendly 409 ahead of the
+   * partial unique indexes). Blocked while the train is out on a dispatched
+   * run, like every other composition edit.
+   */
+  async updateDetails(id: string, dto: UpdateTrainDetailsDto) {
+    await this.dataSource.transaction(async (manager) => {
+      const train = await this.getEditableTrain(manager, id);
+
+      const patch: Partial<Train> = {};
+      if (dto.trainName !== undefined) {
+        patch.trainName = dto.trainName.trim() || null;
+      }
+      const importTrainNumber = dto.importTrainNumber?.trim();
+      const exportTrainNumber = dto.exportTrainNumber?.trim();
+      if (importTrainNumber) patch.importTrainNumber = importTrainNumber;
+      if (exportTrainNumber) patch.exportTrainNumber = exportTrainNumber;
+
+      if (importTrainNumber || exportTrainNumber) {
+        const nextImport = importTrainNumber ?? train.importTrainNumber ?? '';
+        const nextExport = exportTrainNumber ?? train.exportTrainNumber ?? '';
+        const numberClash: { code: string }[] = await manager.query(
+          `SELECT code FROM freight.trains
+            WHERE deleted_at IS NULL
+              AND id != $3
+              AND (import_train_number IN ($1, $2)
+                   OR export_train_number IN ($1, $2)
+                   OR train_number IN ($1, $2))
+            LIMIT 1`,
+          [nextImport, nextExport, train.id],
+        );
+        if (numberClash.length) {
+          throw new ConflictException(
+            `Train number ${nextImport}/${nextExport} is already used by train ${numberClash[0].code}`,
+          );
+        }
+      }
+
+      if (Object.keys(patch).length) {
+        await manager.getRepository(Train).update(train.id, patch);
+      }
+    });
+    return this.getComposition(id);
+  }
+
   /**
    * Relocate the train to another yard. The consist moves as one unit: every
    * coupled locomotive and wagon follows to the new yard (so their current