From c34d77d5d84dc190e0673779a7cbe3b261c422d4 Mon Sep 17 00:00:00 2001
From: Vincent Flyson <vflyson@uberspace.net>
Date: Fri, 23 Aug 2019 23:06:06 -0400
Subject: [PATCH] Revamp resolve_url() and improve code format

---
 Cargo.toml  |  2 +-
 src/html.rs | 16 +++++++++----
 src/http.rs | 68 +++++++++++++++++------------------------------------
 src/main.rs | 15 ++++++++----
 4 files changed, 46 insertions(+), 55 deletions(-)

diff --git a/Cargo.toml b/Cargo.toml
index 14a9cb3..4694a41 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 name = "monolith"
-version = "2.0.8"
+version = "2.0.9"
 authors = ["Sunshine <sunshine@uberspace.net>"]
 description = "CLI tool for saving web pages as a single HTML file"
 
diff --git a/src/html.rs b/src/html.rs
index 100cddd..22052e3 100644
--- a/src/html.rs
+++ b/src/html.rs
@@ -19,7 +19,8 @@ enum NodeMatch {
     Other,
 }
 
-const PNG_PIXEL: &str = "data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAQAAAC1HAwCAAAAC0lEQVR42mNkYAAAAAYAAjCB0C8AAAAASUVORK5CYII=";
+const TRANSPARENT_PIXEL: &str = "data:image/png;base64,\
+iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAQAAAC1HAwCAAAAC0lEQVR42mNkYAAAAAYAAjCB0C8AAAAASUVORK5CYII=";
 
 const JS_DOM_EVENT_ATTRS: [&str; 21] = [
     // Input
@@ -76,7 +77,8 @@ pub fn walk_and_embed_assets(
         NodeData::Comment { .. } => {
             // Note: in case of opt_no_js being set to true, there's no need to worry about
             //       getting rid of comments that may contain scripts, e.g. <!--[if IE]><script>...
-            //       since that's not part of W3C standard and gets ignored by browsers other than IE [5, 9]
+            //       since that's not part of W3C standard and therefore gets ignored
+            //       by browsers other than IE [5, 9]
         }
 
         NodeData::Element {
@@ -130,7 +132,7 @@ pub fn walk_and_embed_assets(
                         if &attr.name.local == "src" {
                             if opt_no_images {
                                 attr.value.clear();
-                                attr.value.push_slice(PNG_PIXEL);
+                                attr.value.push_slice(TRANSPARENT_PIXEL);
                             } else {
                                 let src_full_url = resolve_url(&url, &attr.value.to_string());
                                 let img_datauri = retrieve_asset(
@@ -224,7 +226,13 @@ pub fn walk_and_embed_assets(
                                 opt_user_agent,
                             );
                             let dom = html_to_dom(&iframe_data.unwrap());
-                            walk_and_embed_assets(&src_full_url, &dom.document, opt_no_js, opt_no_images, opt_user_agent);
+                            walk_and_embed_assets(
+                                &src_full_url,
+                                &dom.document,
+                                opt_no_js,
+                                opt_no_images,
+                                opt_user_agent,
+                            );
                             let mut buf: Vec<u8> = Vec::new();
                             serialize(&mut buf, &dom.document, SerializeOpts::default()).unwrap();
                             let iframe_datauri = data_to_dataurl("text/html", &buf);
diff --git a/src/http.rs b/src/http.rs
index 1765f14..f13baf4 100644
--- a/src/http.rs
+++ b/src/http.rs
@@ -9,6 +9,13 @@ lazy_static! {
     static ref REGEX_URL: Regex = Regex::new(r"^https?://").unwrap();
 }
 
+pub fn is_data_url(url: &str) -> Result<bool, String> {
+    match Url::parse(url) {
+        Ok(parsed_url) => Ok(parsed_url.scheme() == "data"),
+        Err(err) => Err(format!("{}", err)),
+    }
+}
+
 pub fn is_valid_url(path: &str) -> bool {
     REGEX_URL.is_match(path)
 }
@@ -18,59 +25,19 @@ pub fn resolve_url(from: &str, to: &str) -> Result<String, ParseError> {
         // (anything, http://site.com/css/main.css)
         to.to_string()
     } else {
-        let mut re = String::new();
-        if is_valid_url(from) {
-            // It's a remote resource (HTTP)
-            if to.starts_with('/') {
-                // (http://site.com/article/1, /...?)
-                let from_url = Url::parse(from)?;
-
-                if to.starts_with("//") {
-                    // (http://site.com/article/1, //images/1.png)
-                    re.push_str(from_url.scheme());
-                    re.push_str(":");
-                    re.push_str(to);
-                } else {
-                    // (http://site.com/article/1, /css/main.css)
-                    re.push_str(from_url.scheme());
-                    re.push_str("://");
-                    re.push_str(from_url.host_str().unwrap());
-                    re.push_str(to);
-                }
-            } else {
-                // (http://site.com, css/main.css)
-                // TODO improve to ensure no // or /// ever happen
-                let base = Url::parse(from)?;
-                re = base.join(to)?.to_string();
-            }
-        } else {
-            // It's a local resource (fs)
-            // TODO improve to ensure no // or /// ever happen
-            // TODO for fs use basepath instead of $from
-            re.push_str(from);
-            re.push_str("/");
-            re.push_str(to);
-        }
-        re
+        Url::parse(from)?.join(to)?.to_string()
     };
 
     Ok(result)
 }
 
-pub fn url_is_data(url: &str) -> Result<bool, String> {
-    match Url::parse(url) {
-        Ok(parsed_url) => Ok(parsed_url.scheme() == "data"),
-        Err(err) => Err(format!("{}", err)),
-    }
-}
-
 pub fn retrieve_asset(
     url: &str,
     as_dataurl: bool,
     as_mime: &str,
     opt_user_agent: &str,
 ) -> Result<String, reqwest::Error> {
-    if url_is_data(&url).unwrap() {
+    if is_data_url(&url).unwrap() {
         Ok(url.to_string())
     } else {
         let client = Client::builder()
@@ -161,6 +128,15 @@ mod tests {
             "https://www.kernel.org/theme/images/logos/tux.png"
         );
 
+        let resolved_url = resolve_url(
+            "https://www.kernel.org",
+            "//another-host.org/theme/images/logos/tux.png",
+        )?;
+        assert_eq!(
+            resolved_url.as_str(),
+            "https://another-host.org/theme/images/logos/tux.png"
+        );
+
         let resolved_url = resolve_url(
             "https://www.kernel.org/category/signatures.html",
             "/theme/images/logos/tux.png",
@@ -183,12 +159,12 @@ mod tests {
     }
 
     #[test]
-    fn test_url_is_data() {
+    fn test_is_data_url() {
         assert!(
-            url_is_data("data:text/html;base64,V2VsY29tZSBUbyBUaGUgUGFydHksIDxiPlBhbDwvYj4h")
+            is_data_url("data:text/html;base64,V2VsY29tZSBUbyBUaGUgUGFydHksIDxiPlBhbDwvYj4h")
                 .unwrap_or(false)
         );
-        assert!(!url_is_data("https://kernel.org").unwrap_or(false));
-        assert!(!url_is_data("//kernel.org").unwrap_or(false));
+        assert!(!is_data_url("https://kernel.org").unwrap_or(false));
+        assert!(!is_data_url("//kernel.org").unwrap_or(false));
     }
 }
diff --git a/src/main.rs b/src/main.rs
index 3e45f97..80b2666 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -6,7 +6,8 @@ use clap::{App, Arg};
 use monolith::html::{html_to_dom, print_dom, walk_and_embed_assets};
 use monolith::http::{is_valid_url, retrieve_asset};
 
-static DEFAULT_USER_AGENT: &str = "Mozilla/5.0 (Macintosh; Intel Mac OS X 10.14; rv:66.0) Gecko/20100101 Firefox/66.0";
+static DEFAULT_USER_AGENT: &str =
+    "Mozilla/5.0 (Macintosh; Intel Mac OS X 10.14; rv:66.0) Gecko/20100101 Firefox/66.0";
 
 fn main() {
     let command = App::new("monolith")
@@ -32,10 +33,16 @@ fn main() {
     let opt_user_agent = command.value_of("user-agent").unwrap_or(DEFAULT_USER_AGENT);
 
     if is_valid_url(arg_target) {
-        let data = retrieve_asset(&arg_target, false, "", opt_user_agent);
-        let dom = html_to_dom(&data.unwrap());
+        let data = retrieve_asset(&arg_target, false, "", opt_user_agent).unwrap();
+        let dom = html_to_dom(&data);
 
-        walk_and_embed_assets(&arg_target, &dom.document, opt_no_js, opt_no_images, opt_user_agent);
+        walk_and_embed_assets(
+            &arg_target,
+            &dom.document,
+            opt_no_js,
+            opt_no_images,
+            opt_user_agent,
+        );
 
         print_dom(&dom.document);
         println!(); // Ensure newline at end of output