From 4cab55c21175b09d600ff65716e2b6210f7eae53 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Joakim=20Hells=C3=A9n?= <tlovinator@gmail.com>
Date: Mon, 5 Feb 2024 06:00:17 +0100
Subject: [PATCH] Fix button for uploading OPML

---
 html.go      |   9 +++--
 html_test.go |   7 +++-
 main.go      |   1 +
 opml.go      |  94 ++++++++++++++++++++++++++++++++++++++++++++
 opml_test.go | 107 +++++++++++++++++++++++++++++++++++++++++++++++++++
 views.go     |  73 +++++++++++++++++++++++++++++++----
 6 files changed, 277 insertions(+), 14 deletions(-)
 create mode 100644 opml.go
 create mode 100644 opml_test.go

diff --git a/html.go b/html.go
index f5732da..b8abadc 100644
--- a/html.go
+++ b/html.go
@@ -17,6 +17,7 @@ type HTMLData struct {
 	Author       string
 	CanonicalURL string
 	Content      string
+	ParseResult  []ParseResult
 }
 
 func minifyHTML(h string) string {
@@ -98,7 +99,7 @@ textarea {
 }
 `
 
-func fullHTML(h HTMLData, ParseResult []ParseResult) string {
+func fullHTML(h HTMLData) string {
 	var sb strings.Builder
 	var errorBuilder strings.Builder
 
@@ -106,9 +107,9 @@ func fullHTML(h HTMLData, ParseResult []ParseResult) string {
 	DatabaseSize := GetDBSize()
 
 	// This is the error message that will be displayed if there are any errors
-	if len(ParseResult) > 0 {
-		errorBuilder.WriteString("<h2>Results</h2><ul>")
-		for _, result := range ParseResult {
+	if len(h.ParseResult) > 0 {
+		errorBuilder.WriteString("<ul>")
+		for _, result := range h.ParseResult {
 			var listItemClass, statusMsg string
 			if result.IsError {
 				listItemClass = "error"
diff --git a/html_test.go b/html_test.go
index 78e5580..93a4293 100644
--- a/html_test.go
+++ b/html_test.go
@@ -34,14 +34,17 @@ func TestMinifyCSS(t *testing.T) {
 // Displays error messages if there are any parse errors
 func TestErrorMessages(t *testing.T) {
 	// Initialize test data
-	h := HTMLData{}
 	parseResult := []ParseResult{
 		{IsError: true, Msg: "Error 1"},
 		{IsError: true, Msg: "Error 2"},
 	}
 
+	h := HTMLData{
+		ParseResult: parseResult,
+	}
+
 	// Invoke function under test
-	result := fullHTML(h, parseResult)
+	result := fullHTML(h)
 
 	// Assert that the result contains the error messages
 	if !strings.Contains(result, "Error 1") || !strings.Contains(result, "Error 2") {
diff --git a/main.go b/main.go
index fa265b7..c3f7923 100644
--- a/main.go
+++ b/main.go
@@ -53,6 +53,7 @@ func main() {
 	r.Get("/api", ApiHandler)
 	r.Get("/feeds", FeedsHandler)
 	r.Post("/add", AddFeedHandler)
+	r.Post("/upload_opml", UploadOpmlHandler)
 
 	log.Println("Listening on http://localhost:8000/ <Ctrl-C> to stop")
 	http.ListenAndServe("127.0.0.1:8000", r)
diff --git a/opml.go b/opml.go
new file mode 100644
index 0000000..501ab36
--- /dev/null
+++ b/opml.go
@@ -0,0 +1,94 @@
+package main
+
+import "encoding/xml"
+
+type opml struct {
+	Head struct {
+		Title string `xml:"title"`
+	} `xml:"head"`
+	Body Body `xml:"body"`
+}
+
+type Body struct {
+	Outlines []Outline `xml:"outline"`
+}
+
+type Outline struct {
+	Outlines []Outline `xml:"outline"`
+	XmlUrl   string    `xml:"xmlUrl,attr,omitempty"`
+	HtmlUrl  string    `xml:"htmlUrl,attr,omitempty"`
+}
+
+func (o *opml) ParseString(s string) error {
+	return xml.Unmarshal([]byte(s), o)
+}
+
+func (o *opml) String() (string, error) {
+	b, err := xml.Marshal(o)
+	if err != nil {
+		return "", err
+	}
+	return xml.Header + string(b), nil
+}
+
+type linksFromOpml struct {
+	XMLLinks  []string `json:"xmlLinks"`
+	HTMLLinks []string `json:"htmlLinks"`
+}
+
+func removeDuplicates(s []string) []string {
+	seen := make(map[string]struct{}, len(s))
+	j := 0
+	for _, v := range s {
+		if _, ok := seen[v]; ok {
+			continue
+		}
+		seen[v] = struct{}{}
+		s[j] = v
+		j++
+	}
+	return s[:j]
+}
+
+func ParseOpml(s string) (linksFromOpml, error) {
+	// Get all the feeds from the OPML and return them as linksFromOpml
+	opml := &opml{}
+	err := opml.ParseString(s)
+	if err != nil {
+		return linksFromOpml{}, err
+	}
+
+	links := linksFromOpml{}
+	for _, outline := range opml.Body.Outlines {
+		links.XMLLinks = append(links.XMLLinks, outline.XmlUrl)
+		links.HTMLLinks = append(links.HTMLLinks, outline.HtmlUrl)
+	}
+
+	// Also check outlines for nested outlines
+	for _, outline := range opml.Body.Outlines {
+		for _, nestedOutline := range outline.Outlines {
+			links.XMLLinks = append(links.XMLLinks, nestedOutline.XmlUrl)
+			links.HTMLLinks = append(links.HTMLLinks, nestedOutline.HtmlUrl)
+		}
+	}
+
+	// Remove any empty strings
+	for i := 0; i < len(links.XMLLinks); i++ {
+		if links.XMLLinks[i] == "" {
+			links.XMLLinks = append(links.XMLLinks[:i], links.XMLLinks[i+1:]...)
+			i--
+		}
+	}
+	for i := 0; i < len(links.HTMLLinks); i++ {
+		if links.HTMLLinks[i] == "" {
+			links.HTMLLinks = append(links.HTMLLinks[:i], links.HTMLLinks[i+1:]...)
+			i--
+		}
+	}
+
+	// Remove any duplicates
+	links.XMLLinks = removeDuplicates(links.XMLLinks)
+	links.HTMLLinks = removeDuplicates(links.HTMLLinks)
+
+	return links, nil
+}
diff --git a/opml_test.go b/opml_test.go
new file mode 100644
index 0000000..180554a
--- /dev/null
+++ b/opml_test.go
@@ -0,0 +1,107 @@
+package main
+
+import "testing"
+
+var opmlExample = `<?xml version="1.0" encoding="utf-8"?>
+<opml version="1.0">
+	<head>
+		<title>My Feeds</title>
+	</head>
+	<body>
+		<outline text="24 ways" htmlUrl="http://24ways.org/" type="rss" xmlUrl="http://feeds.feedburner.com/24ways"/>
+		<outline text="Writing — by Jan" htmlUrl="http://writing.jan.io/" type="rss" xmlUrl="http://writing.jan.io/feed.xml"/>
+	</body>
+</opml> 
+`
+
+var secondOpmlExample = `<?xml version="1.0" encoding="UTF-8"?>
+<opml version="1.0">
+  <head>
+    <title>Engineering Blogs</title>
+  </head>
+  <body>
+    <outline text="Engineering Blogs" title="Engineering Blogs">
+      <outline type="rss" text="8th Light" title="8th Light" xmlUrl="https://8thlight.com/blog/feed/atom.xml" htmlUrl="https://8thlight.com/blog/"/>
+      <outline type="rss" text="A" title="A" xmlUrl="http://www.vertabelo.com/_rss/blog.xml" htmlUrl="http://www.vertabelo.com/blog"/>
+    </outline>
+  </body>
+</opml>
+`
+
+// Test the opml parser
+func TestParseOpml(t *testing.T) {
+	links, err := ParseOpml(opmlExample)
+	if err != nil {
+		t.Error(err)
+	}
+	if len(links.XMLLinks) != 2 {
+		t.Errorf("Expected 2 links, got %d", len(links.XMLLinks))
+	}
+	if len(links.HTMLLinks) != 2 {
+		t.Errorf("Expected 2 links, got %d", len(links.HTMLLinks))
+	}
+
+	// Test that the links are unique
+	links.XMLLinks = removeDuplicates(links.XMLLinks)
+	links.HTMLLinks = removeDuplicates(links.HTMLLinks)
+	if len(links.XMLLinks) != 2 {
+		t.Errorf("Expected 2 links, got %d", len(links.XMLLinks))
+	}
+	if len(links.HTMLLinks) != 2 {
+		t.Errorf("Expected 2 links, got %d", len(links.HTMLLinks))
+	}
+
+	// Test that the links are correct
+	if links.XMLLinks[0] != "http://feeds.feedburner.com/24ways" {
+		t.Errorf("Expected http://feeds.feedburner.com/24ways, got %s", links.XMLLinks[0])
+	}
+	if links.XMLLinks[1] != "http://writing.jan.io/feed.xml" {
+		t.Errorf("Expected http://writing.jan.io/feed.xml, got %s", links.XMLLinks[1])
+	}
+	if links.HTMLLinks[0] != "http://24ways.org/" {
+		t.Errorf("Expected http://24ways.org/, got %s", links.HTMLLinks[0])
+	}
+	if links.HTMLLinks[1] != "http://writing.jan.io/" {
+		t.Errorf("Expected http://writing.jan.io/, got %s", links.HTMLLinks[1])
+	}
+
+}
+
+// Test the opml parser with nested outlines
+func TestParseOpmlNested(t *testing.T) {
+	links, err := ParseOpml(secondOpmlExample)
+	if err != nil {
+		t.Error(err)
+	}
+	if len(links.XMLLinks) != 2 {
+		t.Errorf("Expected 2 links, got %d", len(links.XMLLinks))
+	}
+	if len(links.HTMLLinks) != 2 {
+		t.Errorf("Expected 2 links, got %d", len(links.HTMLLinks))
+	}
+
+	// Test that the links are unique
+	links.XMLLinks = removeDuplicates(links.XMLLinks)
+	links.HTMLLinks = removeDuplicates(links.HTMLLinks)
+	if len(links.XMLLinks) != 2 {
+		t.Errorf("Expected 2 links, got %d", len(links.XMLLinks))
+	}
+	if len(links.HTMLLinks) != 2 {
+		t.Errorf("Expected 2 links, got %d", len(links.HTMLLinks))
+	}
+
+	// Test that the links are correct
+	if links.XMLLinks[0] != "https://8thlight.com/blog/feed/atom.xml" {
+		t.Errorf("Expected https://8thlight.com/blog/feed/atom.xml, got %s", links.XMLLinks[0])
+	}
+	if links.XMLLinks[1] != "http://www.vertabelo.com/_rss/blog.xml" {
+		t.Errorf("Expected http://www.vertabelo.com/_rss/blog.xml, got %s", links.XMLLinks[1])
+	}
+	if links.HTMLLinks[0] != "https://8thlight.com/blog/" {
+		t.Errorf("Expected https://8thlight.com/blog/, got %s", links.HTMLLinks[0])
+	}
+	if links.HTMLLinks[1] != "http://www.vertabelo.com/blog" {
+		t.Errorf("Expected http://www.vertabelo.com/blog, got %s", links.HTMLLinks[1])
+	}
+
+}
diff --git a/views.go b/views.go
index 247a7d7..4b1b88a 100644
--- a/views.go
+++ b/views.go
@@ -1,6 +1,7 @@
 package main
 
 import (
+	"io"
 	"log"
 	"net/http"
 	"strings"
@@ -74,7 +75,7 @@ func IndexHandler(w http.ResponseWriter, _ *http.Request) {
 		CanonicalURL: "http://localhost:8000/",
 		Content:      content,
 	}
-	html := fullHTML(htmlData, nil)
+	html := fullHTML(htmlData)
 	w.Write([]byte(html))
 }
 
@@ -87,7 +88,7 @@ func ApiHandler(w http.ResponseWriter, _ *http.Request) {
 		CanonicalURL: "http://localhost:8000/api",
 		Content:      "<p>Here be dragons.</p>",
 	}
-	html := fullHTML(htmlData, nil)
+	html := fullHTML(htmlData)
 	w.Write([]byte(html))
 }
 func FeedsHandler(w http.ResponseWriter, _ *http.Request) {
@@ -99,7 +100,7 @@ func FeedsHandler(w http.ResponseWriter, _ *http.Request) {
 		CanonicalURL: "http://localhost:8000/feeds",
 		Content:      "<p>Here be feeds.</p>",
 	}
-	html := fullHTML(htmlData, nil)
+	html := fullHTML(htmlData)
 	w.Write([]byte(html))
 }
 
@@ -126,17 +127,73 @@ func AddFeedHandler(w http.ResponseWriter, r *http.Request) {
 
 		// "Add" the feed to the database
 		log.Println("Adding feed:", feed_url)
-	}
+		parseErrors = append(parseErrors, ParseResult{FeedURL: feed_url, Msg: "Added", IsError: false})
 
+	}
 	htmlData := HTMLData{
-		Title:        "FeedVault - Add Feeds",
-		Description:  "FeedVault - Add Feeds",
+		Title:        "FeedVault",
+		Description:  "FeedVault - A feed archive",
 		Keywords:     "RSS, Atom, Feed, Archive",
 		Author:       "TheLovinator",
-		CanonicalURL: "http://localhost:8000/add",
+		CanonicalURL: "http://localhost:8000/",
 		Content:      "<p>Feeds added.</p>",
+		ParseResult:  parseErrors,
 	}
 
-	html := fullHTML(htmlData, parseErrors)
+	html := fullHTML(htmlData)
+	w.Write([]byte(html))
+}
+
+func UploadOpmlHandler(w http.ResponseWriter, r *http.Request) {
+	// Parse the form and get the file
+	r.ParseMultipartForm(10 << 20) // 10 MB
+	file, _, err := r.FormFile("file")
+	if err != nil {
+		http.Error(w, "No file provided", http.StatusBadRequest)
+		return
+	}
+	defer file.Close()
+
+	// Read the file
+	all, err := io.ReadAll(file)
+	if err != nil {
+		http.Error(w, "Failed to read file", http.StatusInternalServerError)
+		return
+	}
+	// Convert the file to a string
+	opml := string(all)
+
+	// Parse the OPML file
+	parseResult := []ParseResult{}
+	links, err := ParseOpml(opml)
+	if err != nil {
+		parseResult = append(parseResult, ParseResult{FeedURL: "/upload_opml", Msg: err.Error(), IsError: true})
+	} else {
+		// Add the feeds to the database
+		for _, feed_url := range links.XMLLinks {
+			log.Println("Adding feed:", feed_url)
+
+			// Validate the URL
+			err := validateURL(feed_url)
+			if err != nil {
+				parseResult = append(parseResult, ParseResult{FeedURL: feed_url, Msg: err.Error(), IsError: true})
+				continue
+			}
+
+			parseResult = append(parseResult, ParseResult{FeedURL: feed_url, Msg: "Added", IsError: false})
+		}
+	}
+
+	// Return the results
+	htmlData := HTMLData{
+		Title:        "FeedVault",
+		Description:  "FeedVault - A feed archive",
+		Keywords:     "RSS, Atom, Feed, Archive",
+		Author:       "TheLovinator",
+		CanonicalURL: "http://localhost:8000/",
+		Content:      "<p>Feeds added.</p>",
+		ParseResult:  parseResult,
+	}
+	html := fullHTML(htmlData)
 	w.Write([]byte(html))
 }