From e8470cb8b96dad498e2aeb5e72be018391741f4f Mon Sep 17 00:00:00 2001
From: blank X <theblankx@protonmail.com>
Date: Mon, 11 Jan 2021 13:46:56 +0700
Subject: [PATCH] Download workers only commit suicide when all chapters are
 retrieved

---
 Cargo.lock               |  2 +-
 Cargo.toml               |  2 +-
 src/commands/download.rs | 43 +++++++++++++++++++++++-----------------
 3 files changed, 27 insertions(+), 20 deletions(-)

diff --git a/Cargo.lock b/Cargo.lock
index c201470..353b8a6 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -330,7 +330,7 @@ dependencies = [
 
 [[package]]
 name = "mangafetchi"
-version = "0.1.4"
+version = "0.1.5"
 dependencies = [
  "quick-xml",
  "reqwest",
diff --git a/Cargo.toml b/Cargo.toml
index b4e0e38..5e6563b 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 name = "mangafetchi"
-version = "0.1.4"
+version = "0.1.5"
 authors = ["blank X <theblankx@protonmail.com>"]
 edition = "2018"
 
diff --git a/src/commands/download.rs b/src/commands/download.rs
index 49f9be9..7127680 100644
--- a/src/commands/download.rs
+++ b/src/commands/download.rs
@@ -13,6 +13,7 @@ extern crate reqwest;
 
 const DOWNLOAD_WORKERS: usize = 5;
 const NON_IMAGE_WAIT_TIME: u64 = 5000;
+const NO_ITEM_WAIT_TIME: u64 = 1000;
 
 pub async fn run(mut args: env::Args) {
     let manga_id = match args.next() {
@@ -50,8 +51,8 @@ pub async fn run(mut args: env::Args) {
             exit(1);
         }
     };
-    let mutex: Arc<Mutex<Vec<(String, PathBuf, String)>>> = Arc::new(Mutex::new(Vec::new()));
-    let mut handles: Option<Vec<JoinHandle<()>>> = None;
+    let mutex = Arc::new(Mutex::new(DownloadData { data: Vec::new(), is_done: false }));
+    let handles: Vec<JoinHandle<()>> = summon_handles(client.clone(), Arc::clone(&mutex)).await;
     for chapter in chapters {
         let cloned_mutex = Arc::clone(&mutex);
         let chapter_pages = utils::get_pages(client.clone(), &chapter, &manga_id).await.unwrap();
@@ -64,22 +65,18 @@ pub async fn run(mut args: env::Args) {
             }
         }
         if !to_extend.is_empty() {
-            cloned_mutex.lock().await.extend(to_extend);
-            if handles.is_none() {
-                handles = Some(summon_handles(client.clone(), cloned_mutex).await);
-            }
+            cloned_mutex.lock().await.data.extend(to_extend);
         }
     }
-    if handles.is_some() {
-        for handle in handles.unwrap() {
-            handle.await.unwrap();
-        }
-    } else {
-        eprintln!("Everything has already been downloaded");
+    {
+        mutex.lock().await.is_done = true;
+    }
+    for handle in handles {
+        handle.await.unwrap();
     }
 }
 
-async fn summon_handles(client: reqwest::Client, mutex: Arc<Mutex<Vec<(String, PathBuf, String)>>>) -> Vec<JoinHandle<()>> {
+async fn summon_handles(client: reqwest::Client, mutex: Arc<Mutex<DownloadData>>) -> Vec<JoinHandle<()>> {
     let mut handles = Vec::with_capacity(DOWNLOAD_WORKERS);
     for worker_id in 0..DOWNLOAD_WORKERS {
         let tcloned_mutex = Arc::clone(&mutex);
@@ -89,12 +86,17 @@ async fn summon_handles(client: reqwest::Client, mutex: Arc<Mutex<Vec<(String, P
             loop {
                 let cloned_mutex = Arc::clone(&tcloned_mutex);
                 let cloned_client = tcloned_client.clone();
-                let mut vec = cloned_mutex.lock().await;
-                if vec.is_empty() {
-                    break;
+                let mut download_data = cloned_mutex.lock().await;
+                if download_data.data.is_empty() {
+                    if download_data.is_done {
+                        break;
+                    }
+                    drop(download_data);
+                    sleep(Duration::from_millis(NO_ITEM_WAIT_TIME)).await;
+                    continue;
                 }
-                let (url, file_name, referer) = vec.remove(0);
-                drop(vec);
+                let (url, file_name, referer) = download_data.data.remove(0);
+                drop(download_data);
                 eprintln!("[DW{}] Downloading {} to {}", worker_id, &url, file_name.display());
                 loop {
                     if utils::download_file(cloned_client.clone(), &url, &file_name, &referer).await.unwrap() {
@@ -109,3 +111,8 @@ async fn summon_handles(client: reqwest::Client, mutex: Arc<Mutex<Vec<(String, P
     }
     handles
 }
+
+struct DownloadData {
+    pub data: Vec<(String, PathBuf, String)>,
+    pub is_done: bool
+}