From 5fe06731fb10018d2d208ca3491801698bfd47e5 Mon Sep 17 00:00:00 2001
From: Stanislav Petrashov <s@petrashov.ru>
Date: Sun, 5 Jul 2020 16:23:43 +0200
Subject: [PATCH] Ensure notes with the same title do not overwrite each other

---
 file/file.go | 15 +++++++--------
 main.go      | 28 ++++++++++++++++++++--------
 2 files changed, 27 insertions(+), 16 deletions(-)

diff --git a/file/file.go b/file/file.go
index 5121b68..f267bb7 100644
--- a/file/file.go
+++ b/file/file.go
@@ -3,6 +3,7 @@ package file
 import (
 	"io"
 	"os"
+	"path/filepath"
 	"regexp"
 	"strings"
 )
@@ -17,21 +18,19 @@ var (
 	dashes = regexp.MustCompile(`[\-_]{2,}`)
 )
 
-// Save a new file in a given dir with the following content
-// If directory doesn't exist it will create it
+// Save a new file in a given dir with the following content.
+// Creates a directory if necessary.
 func Save(dir, name string, content io.Reader) error {
 	if len(name) == 0 {
 		return nil
 	}
 
-	if _, err := os.Stat(dir); os.IsNotExist(err) {
-		err = os.Mkdir(dir, os.ModePerm)
-		if err != nil {
-			return err
-		}
+	err := os.MkdirAll(dir, os.ModePerm)
+	if err != nil {
+		return err
 	}
 
-	output, err := os.Create(dir + "/" + name)
+	output, err := os.Create(filepath.FromSlash(dir + "/" + name))
 	if err != nil {
 		return err
 	}
diff --git a/main.go b/main.go
index 7803b30..81e2ab8 100644
--- a/main.go
+++ b/main.go
@@ -10,7 +10,6 @@ package main
 import (
 	"bytes"
 	"fmt"
-	"io"
 	"log"
 	"os"
 	"path/filepath"
@@ -49,6 +48,11 @@ func main() {
 	run(input, outputDir)
 }
 
+const progressBarTmpl = `Notes: {{counters .}} {{bar . "[" "=" ">" "_" "]" }} {{percent .}} {{etime .}}`
+
+// A map to keep track of what notes are already created
+var notes = map[string]int{}
+
 func run(input, output string) {
 	i, err := os.Open(input)
 	failWhen(err)
@@ -63,29 +67,37 @@ func run(input, output string) {
 	failWhen(err)
 
 	progress := pb.StartNew(len(export.Notes))
-	progress.SetTemplateString(`Notes: {{counters .}} {{bar . "[" "=" ">" "_" "]" }} {{percent .}} {{etime .}}`)
+	progress.SetTemplateString(progressBarTmpl)
 
 	n := export.Notes
 	for i := range n {
 		md, err := internal.Convert(&n[i])
 		failWhen(err)
-		mdFile := filepath.FromSlash(output + "/" + file.BaseName(n[i].Title) + ".md")
-		f, err := os.Create(mdFile)
-		failWhen(err)
-		_, err = io.Copy(f, bytes.NewReader(md.Content))
+		err = file.Save(output, uniqueName(n[i].Title), bytes.NewReader(md.Content))
 		failWhen(err)
 		for _, res := range md.Media {
 			err = file.Save(output+"/"+string(res.Type), res.Name, bytes.NewReader(res.Content))
 			failWhen(err)
 		}
-		err = f.Close()
-		failWhen(err)
 		progress.Increment()
 	}
 	progress.Finish()
 	fmt.Println("Done!")
 }
 
+// uniqueName returns a unique note name
+func uniqueName(title string) string {
+	name := file.BaseName(title) + ".md"
+	if k, exist := notes[name]; exist {
+		notes[name] = k + 1
+		name = fmt.Sprintf("%s-%d.md", file.BaseName(title), k)
+	} else {
+		notes[name] = 1
+	}
+
+	return name
+}
+
 func failWhen(err error) {
 	if err != nil {
 		log.Fatal(err)