file previews no longer continuously spawn threads for existing previews

 - file previews also honor max_preview_size option
 - removed unnecessary return from cursor_move
 - parent_cursor_move now works properly with preview loading
 - reloading now retain directory sizes

3 files changed, 64 insertions, 52 deletions

diff --git a/src/preview/preview_default.rs b/src/preview/preview_default.rs
index d2fd95e..0c5142c 100644
--- a/src/preview/preview_default.rs
+++ b/src/preview/preview_default.rs
@@ -1,15 +1,23 @@
 use std::path;
 
 use crate::context::AppContext;
+use crate::fs::JoshutoMetadata;
 use crate::preview::{preview_dir, preview_file};
 use crate::ui::TuiBackend;
 
-pub fn load_preview_path(context: &mut AppContext, backend: &mut TuiBackend, p: path::PathBuf) {
-    if p.is_dir() {
+pub fn load_preview_path(
+    context: &mut AppContext,
+    backend: &mut TuiBackend,
+    p: path::PathBuf,
+    metadata: JoshutoMetadata,
+) {
+    let preview_options = context.config_ref().preview_options_ref();
+
+    if metadata.is_dir() {
         let need_to_load = context
-            .tab_context_mut()
-            .curr_tab_mut()
-            .history_mut()
+            .tab_context_ref()
+            .curr_tab_ref()
+            .history_ref()
             .get(p.as_path())
             .map(|e| e.need_update())
             .unwrap_or(true);
@@ -17,7 +25,7 @@ pub fn load_preview_path(context: &mut AppContext, backend: &mut TuiBackend, p:
         if need_to_load {
             preview_dir::Background::load_preview(context, p);
         }
-    } else if p.is_file() {
+    } else if metadata.len() <= preview_options.max_preview_size {
         let need_to_load = context
             .preview_context_ref()
             .get_preview(p.as_path())
@@ -26,19 +34,29 @@ pub fn load_preview_path(context: &mut AppContext, backend: &mut TuiBackend, p:
         if need_to_load {
             preview_file::Background::preview_path_with_script(context, backend, p);
         }
+    } else {
     }
 }
 
 pub fn load_preview(context: &mut AppContext, backend: &mut TuiBackend) {
-    let mut p: Option<path::PathBuf> = None;
-    if let Some(curr_list) = context.tab_context_ref().curr_tab_ref().curr_list_ref() {
-        if let Some(index) = curr_list.index {
-            let entry = &curr_list.contents[index];
-            p = Some(entry.file_path().to_path_buf())
+    let mut load_list = Vec::with_capacity(2);
+
+    let curr_tab = context.tab_context_ref().curr_tab_ref();
+    match curr_tab.curr_list_ref() {
+        Some(curr_list) => {
+            if let Some(index) = curr_list.index {
+                let entry = &curr_list.contents[index];
+                load_list.push((entry.file_path().to_path_buf(), entry.metadata.clone()));
+            }
+        }
+        None => {
+            if let Ok(metadata) = JoshutoMetadata::from(curr_tab.cwd()) {
+                load_list.push((curr_tab.cwd().to_path_buf(), metadata));
+            }
         }
     }
 
-    if let Some(p) = p {
-        load_preview_path(context, backend, p);
+    for (path, metadata) in load_list {
+        load_preview_path(context, backend, path, metadata);
     }
 }
diff --git a/src/preview/preview_dir.rs b/src/preview/preview_dir.rs
index b25bd22..713ac0c 100644
--- a/src/preview/preview_dir.rs
+++ b/src/preview/preview_dir.rs
@@ -12,11 +12,13 @@ pub struct Foreground {}
 impl Foreground {
     pub fn load_preview(context: &mut AppContext, p: path::PathBuf) -> io::Result<()> {
         let options = context.config_ref().display_options_ref().clone();
-        context
-            .tab_context_mut()
-            .curr_tab_mut()
-            .history_mut()
-            .create_or_soft_update(p.as_path(), &options)?;
+        let history = context.tab_context_mut().curr_tab_mut().history_mut();
+        if history
+            .create_or_soft_update(p.as_path(), &options)
+            .is_err()
+        {
+            history.remove(p.as_path());
+        }
         Ok(())
     }
 }
@@ -25,31 +27,17 @@ pub struct Background {}
 
 impl Background {
     pub fn load_preview(context: &mut AppContext, p: path::PathBuf) -> thread::JoinHandle<()> {
-        let need_to_load = match context
-            .tab_context_mut()
-            .curr_tab_mut()
-            .history_mut()
-            .get(p.as_path())
-        {
-            Some(entry) => entry.need_update(),
-            None => true,
-        };
-        if need_to_load {
-            let event_tx = context.events.event_tx.clone();
-            let options = context.config_ref().display_options_ref().clone();
-            let handle = thread::spawn(move || {
-                match JoshutoDirList::new(p, &options) {
-                    Ok(dirlist) => {
-                        let _ = event_tx.send(AppEvent::PreviewDir(Ok(dirlist)));
-                    }
-                    Err(_) => {}
+        let event_tx = context.events.event_tx.clone();
+        let options = context.config_ref().display_options_ref().clone();
+        let handle = thread::spawn(move || {
+            match JoshutoDirList::from_path(p, &options) {
+                Ok(dirlist) => {
+                    let _ = event_tx.send(AppEvent::PreviewDir(Ok(dirlist)));
                 }
-                ()
-            });
-            handle
-        } else {
-            let handle = thread::spawn(|| ());
-            handle
-        }
+                Err(_) => {}
+            }
+            ()
+        });
+        handle
     }
 }
diff --git a/src/preview/preview_file.rs b/src/preview/preview_file.rs
index 4d454e7..cd8a6db 100644
--- a/src/preview/preview_file.rs
+++ b/src/preview/preview_file.rs
@@ -10,20 +10,24 @@ use crate::event::AppEvent;
 use crate::ui::{self, TuiBackend};
 
 #[derive(Clone, Debug)]
+pub enum PreviewState {
+    NoPreview,
+    SomePreview(FilePreview),
+}
+
+#[derive(Clone, Debug)]
 pub struct FilePreview {
-    pub _path: path::PathBuf,
     pub status: std::process::ExitStatus,
     pub output: String,
 }
 
-impl std::convert::From<(path::PathBuf, Output)> for FilePreview {
-    fn from((p, output): (path::PathBuf, Output)) -> Self {
+impl std::convert::From<Output> for FilePreview {
+    fn from(output: Output) -> Self {
         let s = String::from_utf8_lossy(&output.stdout).to_string();
         let s2 = s.replace('\t', "        ");
         let s = s2.to_string();
         let status = output.status;
         Self {
-            _path: p,
             status,
             output: s,
         }
@@ -93,7 +97,7 @@ impl Background {
     pub fn preview_path_with_script(
         context: &AppContext,
         backend: &mut TuiBackend,
-        p: path::PathBuf,
+        path: path::PathBuf,
     ) {
         let preview_options = context.config_ref().preview_options_ref();
         let config = context.config_ref();
@@ -113,7 +117,7 @@ impl Background {
             let script = script.clone();
             let event_tx = context.clone_event_tx();
             let _ = thread::spawn(move || {
-                let file_full_path = p.as_path();
+                let file_full_path = path.as_path();
 
                 let res = Command::new(script)
                     .arg(file_full_path)
@@ -124,10 +128,12 @@ impl Background {
                     .output();
                 match res {
                     Ok(output) => {
-                        let preview = FilePreview::from((p, output));
-                        let _ = event_tx.send(AppEvent::PreviewFile(preview));
+                        let preview = FilePreview::from(output);
+                        let _ = event_tx.send(AppEvent::PreviewFile(path, Ok(preview)));
+                    }
+                    Err(e) => {
+                        let _ = event_tx.send(AppEvent::PreviewFile(path, Err(e)));
                     }
-                    Err(_) => {}
                 }
             });
         }