chore: import upstream snapshot with attribution

apps/sim/app/api/chat/validate/route.ts

@@ -0,0 +1,59 @@
+import { db } from '@sim/db'
+import { chat } from '@sim/db/schema'
+import { createLogger } from '@sim/logger'
+import { and, eq, isNull } from 'drizzle-orm'
+import type { NextRequest } from 'next/server'
+import { identifierValidationQuerySchema } from '@/lib/api/contracts/chats'
+import { getValidationErrorMessage } from '@/lib/api/server'
+import { withRouteHandler } from '@/lib/core/utils/with-route-handler'
+import { createErrorResponse, createSuccessResponse } from '@/app/api/workflows/utils'
+
+const logger = createLogger('ChatValidateAPI')
+
+/**
+ * GET endpoint to validate chat identifier availability
+ */
+export const GET = withRouteHandler(async (request: NextRequest) => {
+  try {
+    const { searchParams } = new URL(request.url)
+    const identifier = searchParams.get('identifier')
+
+    const validation = identifierValidationQuerySchema.safeParse({ identifier })
+
+    if (!validation.success) {
+      const errorMessage = getValidationErrorMessage(validation.error, 'Invalid identifier')
+      logger.warn(`Validation error: ${errorMessage}`)
+
+      if (identifier && !/^[a-z0-9-]+$/.test(identifier)) {
+        return createSuccessResponse({
+          available: false,
+          error: errorMessage,
+        })
+      }
+
+      return createErrorResponse(errorMessage, 400)
+    }
+
+    const { identifier: validatedIdentifier } = validation.data
+
+    const existingChat = await db
+      .select({ id: chat.id })
+      .from(chat)
+      .where(and(eq(chat.identifier, validatedIdentifier), isNull(chat.archivedAt)))
+      .limit(1)
+
+    const isAvailable = existingChat.length === 0
+
+    logger.debug(
+      `Identifier "${validatedIdentifier}" availability check: ${isAvailable ? 'available' : 'taken'}`
+    )
+
+    return createSuccessResponse({
+      available: isAvailable,
+      error: isAvailable ? null : 'This identifier is already in use',
+    })
+  } catch (error: any) {
+    logger.error('Error validating chat identifier:', error)
+    return createErrorResponse(error.message || 'Failed to validate identifier', 500)
+  }
+})