Use block ids to deduplicate backref lines

backref.go

@@ -50,28 +50,36 @@ func processBackrefsForPage(page Page, refs Refs) error {
 	content := page.Content
 
 	var listItems []struct {
+		Id       string
 		Indented int
 		Text     string
 	}
 
+	var links []ParsedLink
 	err := json.NewDecoder(strings.NewReader(content)).Decode(&listItems)
 	if err == nil {
-		pageText := ""
 		for _, item := range listItems {
-			pageText += strings.Repeat("  ", item.Indented) + "* " + item.Text + "\n"
+			foundLinks, err := ParseLinks(item.Id, item.Text)
+			if err != nil {
+				continue
 			}
-
-		content = pageText
+			links = append(links, foundLinks...)
 		}
-
-	links, err := ParseLinks(content)
-
+	} else {
+		links, err = ParseLinks(page.Name, page.Content)
 		if err != nil {
 			return err
 		}
+	}
 
+link:
 	for _, link := range links {
-		// FIXME: this produces duplicates
+		for i, ref := range refs[link.PageName] {
+			if ref.Link.Id == link.Id {
+				refs[link.PageName][i].Link = link
+				continue link
+			}
+		}
 		refs[link.PageName] = append(refs[link.PageName], Reference{link, page.Name})
 	}
 

util.go

@@ -10,6 +10,7 @@ import (
 )
 
 type ParsedLink struct {
+	Id       string
 	Name     string
 	PageName string
 	Line     string
@@ -31,7 +32,7 @@ func RandStringBytes(n int) string {
 	return string(b)
 }
 
-func ParseLinks(content string) ([]ParsedLink, error) {
+func ParseLinks(blockId string, content string) ([]ParsedLink, error) {
 	hrefRE := regexp.MustCompile(`(#?\[\[\s*([^\]]+)\s*\]\])`)
 
 	scanner := bufio.NewScanner(strings.NewReader(content))
@@ -56,7 +57,7 @@ func ParseLinks(content string) ([]ParsedLink, error) {
 			link = strings.TrimSuffix(link, "]]")
 			link = strings.TrimSpace(link)
 			l := cleanNameURL(link)
-			result = append(result, ParsedLink{link, l, line})
+			result = append(result, ParsedLink{blockId, link, l, line})
 		}
 	}