feat: make cross device moves possible

main.go

@@ -230,7 +230,7 @@ func handleExistingFile(cfg config, fileExistsResponse FileExistsResult) error {
 	subfolder := fmt.Sprintf("%s %s - %s.%s", date.Format("20060102"), corr, itemName, extension)
 	newPath := filepath.Join(curDir, subfolder)
 
-	if err := os.Rename(fileExistsResponse.File, newPath); err != nil {
+	if err := MoveFile(fileExistsResponse.File, newPath); err != nil {
 		return fmt.Errorf("move file: %w", err)
 	}
 

util.go

@@ -0,0 +1,40 @@
+package main
+
+import (
+	"fmt"
+	"io"
+	"os"
+)
+
+// MoveFile moves a file across file system boundaries
+// taken from https://stackoverflow.com/questions/50740902/move-a-file-to-a-different-drive-with-go
+func MoveFile(sourcePath, destPath string) error {
+	inputFile, err := os.Open(sourcePath)
+	if err != nil {
+		return fmt.Errorf("Couldn't open source file: %w", err)
+	}
+	defer inputFile.Close()
+
+	outputFile, err := os.Create(destPath)
+	if err != nil {
+		return fmt.Errorf("Couldn't open dest file: %w", err)
+	}
+	defer outputFile.Close()
+
+	_, err = io.Copy(outputFile, inputFile)
+	if err != nil {
+		return fmt.Errorf("Couldn't copy to dest from source: %w", err)
+	}
+
+	// for Windows, close before trying to remove: https://stackoverflow.com/a/64943554/246801
+	err = inputFile.Close()
+	if err != nil {
+		return fmt.Errorf("Couldn't close input: %w", err)
+	}
+
+	err = os.Remove(sourcePath)
+	if err != nil {
+		return fmt.Errorf("Couldn't remove source file: %w", err)
+	}
+	return nil
+}