move preview area into PreviewContext

 - move a bunch of methods out into functions

13 files changed, 151 insertions, 123 deletions

diff --git a/src/commands/bulk_rename.rs b/src/commands/bulk_rename.rs
index 9cc7f26..816ff5e 100644
--- a/src/commands/bulk_rename.rs
+++ b/src/commands/bulk_rename.rs
@@ -6,6 +6,7 @@ use std::process;
 
 use rand::Rng;
 
+use crate::context::remove_external_preview;
 use crate::context::AppContext;
 use crate::error::{AppError, AppErrorKind, AppResult};
 use crate::ui::AppBackend;
@@ -125,10 +126,10 @@ pub fn _bulk_rename(context: &mut AppContext) -> AppResult {
 }
 
 pub fn bulk_rename(context: &mut AppContext, backend: &mut AppBackend) -> AppResult {
-    context.remove_external_preview();
+    remove_external_preview(context);
     backend.terminal_drop();
     let res = _bulk_rename(context);
-    backend.terminal_restore(context.config_ref().mouse_support)?;
+    backend.terminal_restore()?;
     reload::soft_reload_curr_tab(context)?;
     res
 }
diff --git a/src/commands/custom_search.rs b/src/commands/custom_search.rs
index a9d4405..422143e 100644
--- a/src/commands/custom_search.rs
+++ b/src/commands/custom_search.rs
@@ -57,7 +57,7 @@ pub fn custom_search(
             .stdout(Stdio::piped())
             .spawn()?
             .wait_with_output()?;
-        backend.terminal_restore(context.config_ref().mouse_support)?;
+        backend.terminal_restore()?;
         cmd_result
     } else {
         cmd.output()?
diff --git a/src/commands/fzf.rs b/src/commands/fzf.rs
index 9c60c54..bc4667a 100644
--- a/src/commands/fzf.rs
+++ b/src/commands/fzf.rs
@@ -51,7 +51,7 @@ pub fn fzf_multi(
 }
 
 fn fzf_impl(
-    context: &mut AppContext,
+    _context: &mut AppContext,
     backend: &mut AppBackend,
     items: Vec<String>,
     args: Vec<String>,
@@ -68,7 +68,7 @@ fn fzf_impl(
     let mut fzf = match cmd.spawn() {
         Ok(child) => child,
         Err(e) => {
-            backend.terminal_restore(context.config_ref().mouse_support)?;
+            backend.terminal_restore()?;
             return Err(AppError::from(e));
         }
     };
@@ -82,7 +82,7 @@ fn fzf_impl(
     }
 
     let fzf_output = fzf.wait_with_output();
-    backend.terminal_restore(context.config_ref().mouse_support)?;
+    backend.terminal_restore()?;
 
     if let Ok(output) = fzf_output {
         if output.status.success() {
diff --git a/src/commands/open_file.rs b/src/commands/open_file.rs
index d206f35..0d248e9 100644
--- a/src/commands/open_file.rs
+++ b/src/commands/open_file.rs
@@ -60,7 +60,7 @@ where
     } else {
         backend.terminal_drop();
         let res = execute_and_wait(option, files);
-        backend.terminal_restore(context.config_ref().mouse_support)?;
+        backend.terminal_restore()?;
         res?;
     }
     Ok(())
@@ -79,7 +79,7 @@ fn _open_with_xdg(
         backend.terminal_drop();
         let handle = open::that_in_background(path);
         let result = handle.join();
-        backend.terminal_restore(context.config_ref().mouse_support)?;
+        backend.terminal_restore()?;
         if let Ok(result) = result {
             result?;
         }
@@ -136,7 +136,7 @@ where
                         let mut option = ProgramEntry::new(String::from(cmd));
                         option.args(args_iter);
                         let res = execute_and_wait(&option, files);
-                        backend.terminal_restore(context.config_ref().mouse_support)?;
+                        backend.terminal_restore()?;
                         res?
                     }
                 }
diff --git a/src/commands/show_help.rs b/src/commands/show_help.rs
index d77dd63..6c98f79 100644
--- a/src/commands/show_help.rs
+++ b/src/commands/show_help.rs
@@ -3,6 +3,7 @@ use std::cmp::Ordering;
 use termion::event::{Event, Key};
 
 use crate::config::clean::keymap::AppKeyMapping;
+use crate::context::remove_external_preview;
 use crate::context::AppContext;
 use crate::error::AppResult;
 use crate::event::process_event;
@@ -30,7 +31,7 @@ pub fn help_loop(
             widgets::get_keymap_table(&keymap_t.default_view, &search_query[1..], sort_by)
         };
 
-        context.remove_external_preview();
+        remove_external_preview(context);
         backend.render(TuiHelp::new(&keymap, &mut offset, &search_query));
 
         let event = match context.poll_event() {
diff --git a/src/commands/sub_process.rs b/src/commands/sub_process.rs
index e1a5262..2e5a1c8 100644
--- a/src/commands/sub_process.rs
+++ b/src/commands/sub_process.rs
@@ -126,7 +126,7 @@ pub fn sub_process(
             // shell command and restore it afterwards
             backend.terminal_drop();
             execute_sub_process(context, words, mode)?;
-            backend.terminal_restore(context.config_ref().mouse_support)?;
+            backend.terminal_restore()?;
             let _ = reload::soft_reload_curr_tab(context);
             context
                 .message_queue_mut()
diff --git a/src/commands/zoxide.rs b/src/commands/zoxide.rs
index a065117..222bb9d 100644
--- a/src/commands/zoxide.rs
+++ b/src/commands/zoxide.rs
@@ -49,7 +49,7 @@ pub fn zoxide_query_interactive(context: &mut AppContext, backend: &mut AppBacke
         .spawn()?;
     let zoxide_output = zoxide_process.wait_with_output()?;
 
-    backend.terminal_restore(context.config_ref().mouse_support)?;
+    backend.terminal_restore()?;
 
     if zoxide_output.status.success() {
         if let Ok(zoxide_str) = std::str::from_utf8(&zoxide_output.stdout) {
diff --git a/src/context/app_context.rs b/src/context/app_context.rs
index a524c6e..4b7f8b7 100644
--- a/src/context/app_context.rs
+++ b/src/context/app_context.rs
@@ -1,7 +1,5 @@
 use std::collections::HashSet;
-use std::process;
 use std::sync::mpsc;
-use std::thread;
 
 use crate::commands::quit::QuitAction;
 use crate::config::clean::app::AppConfig;
@@ -12,7 +10,7 @@ use crate::context::{
 };
 use crate::event::{AppEvent, Events};
 use crate::preview::preview_file::PreviewFileState;
-use crate::ui::{views, AppBackend, PreviewArea};
+use crate::ui::AppBackend;
 use crate::Args;
 use notify::{RecursiveMode, Watcher};
 use ratatui_image::picker::Picker;
@@ -37,7 +35,7 @@ pub struct AppContext {
     // context related to io workers
     worker_context: WorkerContext,
     // context related to previews
-    preview_context: PreviewContext,
+    pub preview_context: PreviewContext,
     // context related to command line
     commandline_context: CommandLineContext,
     // user interface context; data which is input to both, the UI rendering and the app state
@@ -46,9 +44,6 @@ pub struct AppContext {
     watcher: notify::RecommendedWatcher,
     // list of watched paths; seems not to be possible to get them from a notify::Watcher
     watched_paths: HashSet<path::PathBuf>,
-    // the last preview area (or None if now preview shown) to check if a preview hook script needs
-    // to be called
-    preview_area: Option<PreviewArea>,
     // the stdout of the last `shell` command
     pub last_stdout: Option<String>,
 }
@@ -97,6 +92,7 @@ impl AppContext {
         Self {
             quit: QuitAction::DoNot,
             events,
+            config,
             args,
             tab_context: TabContext::new(),
             local_state: None,
@@ -106,99 +102,12 @@ impl AppContext {
             preview_context: PreviewContext::new(picker, preview_script, event_tx),
             ui_context: UiContext { layout: vec![] },
             commandline_context,
-            config,
             watcher,
             watched_paths,
-            preview_area: None,
             last_stdout: None,
         }
     }
 
-    /// Calls the "preview shown hook script" if it's configured.
-    ///
-    /// This method takes the current preview area as argument to check for both, the path of the
-    /// currently previewed file and the geometry of the preview area.
-    fn call_preview_shown_hook(&self, preview_area: PreviewArea) {
-        let preview_options = self.config_ref().preview_options_ref();
-        let preview_shown_hook_script = preview_options.preview_shown_hook_script.as_ref();
-        if let Some(hook_script) = preview_shown_hook_script {
-            let hook_script = hook_script.to_path_buf();
-            let _ = thread::spawn(move || {
-                let _ = process::Command::new(hook_script.as_path())
-                    .arg(preview_area.file_preview_path.as_path())
-                    .arg(preview_area.preview_area.x.to_string())
-                    .arg(preview_area.preview_area.y.to_string())
-                    .arg(preview_area.preview_area.width.to_string())
-                    .arg(preview_area.preview_area.height.to_string())
-                    .status();
-            });
-        }
-    }
-
-    /// Calls the "preview removed hook script" if it's configured.
-    fn call_preview_removed_hook(&self) {
-        let preview_options = self.config_ref().preview_options_ref();
-        let preview_removed_hook_script = preview_options.preview_removed_hook_script.as_ref();
-        if let Some(hook_script) = preview_removed_hook_script {
-            let hook_script = hook_script.to_path_buf();
-            let _ = thread::spawn(|| {
-                let _ = process::Command::new(hook_script).status();
-            });
-        }
-    }
-
-    /// Updates the external preview to the current preview in Joshuto.
-    ///
-    /// The function checks if the current preview content is the same as the preview content which
-    /// has been last communicated to an external preview logic with the preview hook scripts.
-    /// If the preview content has changed, one of the hook scripts is called. Either the "preview
-    /// shown hook", if a preview is shown in Joshuto, or the "preview removed hook", if Joshuto has
-    /// changed from an entry with preview to an entry without a preview.
-    ///
-    /// This function shall be called each time a change of Joshuto's preview can be expected.
-    /// (As of now, it's called in each cycle of the main loop.)
-    pub fn update_external_preview(&mut self) {
-        let layout = &self.ui_context_ref().layout;
-        let new_preview_area = views::calculate_preview(self, layout[2]);
-        match new_preview_area.as_ref() {
-            Some(new) => {
-                let should_preview = if let Some(old) = &self.preview_area {
-                    new.file_preview_path != old.file_preview_path
-                        || new.preview_area != old.preview_area
-                } else {
-                    true
-                };
-                if should_preview {
-                    self.call_preview_shown_hook(new.clone())
-                }
-            }
-            None => {
-                if self.preview_area.is_some() {
-                    self.call_preview_removed_hook()
-                }
-            }
-        }
-        self.preview_area = new_preview_area
-    }
-
-    /// Remove the external preview, if any is present.
-    ///
-    /// If the last preview hook script called was the "preview shown hook", this function will
-    /// call the "preview removed hook" to remove any external preview.
-    /// Otherwise it won't do anything.
-    ///
-    /// To restore the external preview, `update_external_preview` is called which will detect the
-    /// difference and call the "preview shown hook" again for the current preview (if any).
-    ///
-    /// This function can be called if an external preview shall be temporarily removed, for example
-    /// when entering the help screen.
-    pub fn remove_external_preview(&mut self) {
-        if self.preview_area.is_some() {
-            self.call_preview_removed_hook();
-            self.preview_area = None;
-        }
-    }
-
     /// Updates the file system supervision with the currently shown directories.
     pub fn update_watcher(&mut self) {
         // collect the paths that shall be watched...
diff --git a/src/context/preview_context.rs b/src/context/preview_context.rs
index 57184a8..ad49cfc 100644
--- a/src/context/preview_context.rs
+++ b/src/context/preview_context.rs
@@ -1,7 +1,7 @@
 use std::collections::HashMap;
 use std::error::Error;
 use std::path::{self, PathBuf};
-use std::process::{Command, Stdio};
+use std::process::{self, Command, Stdio};
 use std::sync::mpsc::{self, Sender};
 use std::sync::Mutex;
 use std::{io, thread};
@@ -11,13 +11,16 @@ use ratatui_image::picker::Picker;
 use ratatui_image::protocol::Protocol;
 use ratatui_image::Resize;
 
+use crate::config::clean::app::preview::PreviewOption;
 use crate::config::clean::app::AppConfig;
 use crate::event::{AppEvent, PreviewData};
 use crate::lazy_static;
 use crate::preview::preview_file::{FilePreview, PreviewFileState};
-use crate::ui::{views, AppBackend};
+use crate::ui::{views, AppBackend, PreviewArea};
 use crate::AppContext;
 
+use super::{TabContext, UiContext};
+
 lazy_static! {
     static ref GUARD: Mutex<()> = Mutex::new(());
 }
@@ -25,10 +28,15 @@ lazy_static! {
 type FilePreviewMetadata = HashMap<path::PathBuf, PreviewFileState>;
 
 pub struct PreviewContext {
+    // the last preview area (or None if now preview shown) to check if a preview hook script needs
+    // to be called
+    pub preview_area: Option<PreviewArea>,
+    // hashmap of cached previews
     previews: FilePreviewMetadata,
     image_preview: Option<(PathBuf, Box<dyn Protocol>)>,
     sender_script: Sender<(PathBuf, Rect)>,
     sender_image: Option<Sender<(PathBuf, Rect)>>,
+    // for telling main thread when previews are ready
     event_ts: Sender<AppEvent>,
 }
 
@@ -88,6 +96,7 @@ impl PreviewContext {
         });
 
         PreviewContext {
+            preview_area: None,
             previews: HashMap::new(),
             image_preview: None,
             sender_script,
@@ -190,6 +199,21 @@ impl PreviewContext {
         }
     }
 
+    pub fn update_external_preview(&mut self, preview_area: Option<PreviewArea>) {
+        self.preview_area = preview_area;
+    }
+
+    /// Updates the external preview to the current preview in Joshuto.
+    ///
+    /// The function checks if the current preview content is the same as the preview content which
+    /// has been last communicated to an external preview logic with the preview hook scripts.
+    /// If the preview content has changed, one of the hook scripts is called. Either the "preview
+    /// shown hook", if a preview is shown in Joshuto, or the "preview removed hook", if Joshuto has
+    /// changed from an entry with preview to an entry without a preview.
+    ///
+    /// This function shall be called each time a change of Joshuto's preview can be expected.
+    /// (As of now, it's called in each cycle of the main loop.)
+
     fn backend_rect(config: &AppConfig, backend: &AppBackend) -> io::Result<Rect> {
         let area = backend.terminal_ref().size()?;
         let area = Rect {
@@ -213,3 +237,80 @@ impl PreviewContext {
         io::Error::new(io::ErrorKind::Other, format!("{err}"))
     }
 }
+
+/// Calls the "preview removed hook script" if it's configured.
+pub fn call_preview_removed_hook(preview_options: &PreviewOption) {
+    let preview_removed_hook_script = preview_options.preview_removed_hook_script.as_ref();
+    if let Some(hook_script) = preview_removed_hook_script {
+        let hook_script = hook_script.to_path_buf();
+        let _ = thread::spawn(|| {
+            let _ = process::Command::new(hook_script).status();
+        });
+    }
+}
+
+pub fn calculate_external_preview(
+    tab_context: &TabContext,
+    preview_context: &PreviewContext,
+    ui_context: &UiContext,
+    preview_options: &PreviewOption,
+) -> Option<PreviewArea> {
+    let layout = &ui_context.layout;
+    let preview_area = views::calculate_preview(tab_context, preview_context, layout[2]);
+    match preview_area.as_ref() {
+        Some(new_preview_area) => {
+            let should_preview = if let Some(old) = &preview_context.preview_area {
+                new_preview_area.file_preview_path != old.file_preview_path
+                    || new_preview_area.preview_area != old.preview_area
+            } else {
+                true
+            };
+            if should_preview {
+                call_preview_shown_hook(new_preview_area.clone(), preview_options)
+            }
+        }
+        None => {
+            if preview_context.preview_area.is_some() {
+                call_preview_removed_hook(preview_options)
+            }
+        }
+    }
+    preview_area
+}
+/// Calls the "preview shown hook script" if it's configured.
+///
+/// This method takes the current preview area as argument to check for both, the path of the
+/// currently previewed file and the geometry of the preview area.
+fn call_preview_shown_hook(preview_area: PreviewArea, preview_options: &PreviewOption) {
+    let preview_shown_hook_script = preview_options.preview_shown_hook_script.as_ref();
+    if let Some(hook_script) = preview_shown_hook_script {
+        let hook_script = hook_script.to_path_buf();
+        let _ = thread::spawn(move || {
+            let _ = process::Command::new(hook_script.as_path())
+                .arg(preview_area.file_preview_path.as_path())
+                .arg(preview_area.preview_area.x.to_string())
+                .arg(preview_area.preview_area.y.to_string())
+                .arg(preview_area.preview_area.width.to_string())
+                .arg(preview_area.preview_area.height.to_string())
+                .status();
+        });
+    }
+}
+
+/// Remove the external preview, if any is present.
+///
+/// If the last preview hook script called was the "preview shown hook", this function will
+/// call the "preview removed hook" to remove any external preview.
+/// Otherwise it won't do anything.
+///
+/// To restore the external preview, `update_external_preview` is called which will detect the
+/// difference and call the "preview shown hook" again for the current preview (if any).
+///
+/// This function can be called if an external preview shall be temporarily removed, for example
+/// when entering the help screen.
+pub fn remove_external_preview(context: &mut AppContext) {
+    if context.preview_context_mut().preview_area.take().is_some() {
+        let preview_options = context.config_ref().preview_options_ref();
+        call_preview_removed_hook(preview_options);
+    }
+}
diff --git a/src/main.rs b/src/main.rs
index 02ea567..cae9c55 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -157,6 +157,7 @@ fn run_main(args: Args) -> Result<i32, AppError> {
     // make sure all configs have been loaded before starting
     let config = AppConfig::get_config();
     let keymap = AppKeyMapping::get_config();
+
     lazy_static::initialize(&THEME_T);
     lazy_static::initialize(&MIMETYPE_T);
     lazy_static::initialize(&PREVIEW_T);
@@ -167,9 +168,10 @@ fn run_main(args: Args) -> Result<i32, AppError> {
     lazy_static::initialize(&USERNAME);
     lazy_static::initialize(&HOSTNAME);
 
+    let mouse_support = config.mouse_support;
     let mut context = AppContext::new(config, args.clone());
     {
-        let mut backend: ui::AppBackend = ui::AppBackend::new(context.config_ref().mouse_support)?;
+        let mut backend: ui::AppBackend = ui::AppBackend::new(mouse_support)?;
         run::run_loop(&mut backend, &mut context, keymap)?;
     }
     run_quit(&args, &context)?;
diff --git a/src/run.rs b/src/run.rs
index 958fe80..884564c 100644
--- a/src/run.rs
+++ b/src/run.rs
@@ -1,5 +1,6 @@
 use crate::commands::quit::QuitAction;
 use crate::config::clean::keymap::AppKeyMapping;
+use crate::context::calculate_external_preview;
 use crate::context::AppContext;
 use crate::event::process_event;
 use crate::event::AppEvent;
@@ -53,7 +54,17 @@ pub fn run_loop(
             backend.render(TuiView::new(context));
 
             // invoke preview hooks, if appropriate
-            context.update_external_preview();
+            {
+                let new_preview_area = calculate_external_preview(
+                    context.tab_context_ref(),
+                    context.preview_context_ref(),
+                    context.ui_context_ref(),
+                    context.config_ref().preview_options_ref(),
+                );
+                context
+                    .preview_context_mut()
+                    .update_external_preview(new_preview_area);
+            }
         }
 
         // wait for an event and pop it
diff --git a/src/ui/backend.rs b/src/ui/backend.rs
index 4b5b124..70c36ea 100644
--- a/src/ui/backend.rs
+++ b/src/ui/backend.rs
@@ -8,12 +8,6 @@ use termion::screen::IntoAlternateScreen;
 
 use termion::input::MouseTerminal;
 
-trait New {
-    fn new() -> io::Result<Self>
-    where
-        Self: Sized;
-}
-
 pub enum Screen {
     WithMouse(MouseTerminal<AlternateScreen<RawTerminal<std::io::Stdout>>>),
     WithoutMouse(AlternateScreen<RawTerminal<std::io::Stdout>>),
@@ -54,6 +48,7 @@ pub type TuiTerminal = ratatui::Terminal<TermionBackend<Screen>>;
 
 pub struct AppBackend {
     pub terminal: Option<TuiTerminal>,
+    pub mouse_support: bool,
 }
 
 impl AppBackend {
@@ -66,6 +61,7 @@ impl AppBackend {
         let mut terminal = ratatui::Terminal::new(backend)?;
         terminal.hide_cursor()?;
         Ok(Self {
+            mouse_support,
             terminal: Some(terminal),
         })
     }
@@ -93,8 +89,8 @@ impl AppBackend {
         let _ = stdout().flush();
     }
 
-    pub fn terminal_restore(&mut self, mouse_support: bool) -> io::Result<()> {
-        let mut new_backend = Self::new(mouse_support)?;
+    pub fn terminal_restore(&mut self) -> io::Result<()> {
+        let mut new_backend = Self::new(self.mouse_support)?;
         std::mem::swap(&mut self.terminal, &mut new_backend.terminal);
         Ok(())
     }
diff --git a/src/ui/views/tui_folder_view.rs b/src/ui/views/tui_folder_view.rs
index 2d9538c..4f49ab1 100644
--- a/src/ui/views/tui_folder_view.rs
+++ b/src/ui/views/tui_folder_view.rs
@@ -6,7 +6,7 @@ use ratatui::text::Span;
 use ratatui::widgets::{Block, Borders, Paragraph, Widget, Wrap};
 use ratatui_image::Image;
 
-use crate::context::AppContext;
+use crate::context::{AppContext, PreviewContext, TabContext};
 use crate::preview::preview_dir::PreviewDirState;
 use crate::preview::preview_file::PreviewFileState;
 use crate::ui;
@@ -208,7 +208,11 @@ impl<'a> Widget for TuiFolderView<'a> {
                     if let Some(PreviewFileState::Success(data)) =
                         preview_context.previews_ref().get(entry.file_path())
                     {
-                        let preview_area = calculate_preview(self.context, layout_rect[2]);
+                        let preview_area = calculate_preview(
+                            self.context.tab_context_ref(),
+                            self.context.preview_context_ref(),
+                            layout_rect[2],
+                        );
                         if let Some(preview_area) = preview_area {
                             let area = Rect {
                                 x: preview_area.preview_area.x,
@@ -324,9 +328,12 @@ pub fn calculate_layout_with_borders(area: Rect, constraints: &[Constraint; 3])
     vec![inner1, layout_rect[1], inner3]
 }
 
-pub fn calculate_preview(context: &AppContext, rect: Rect) -> Option<PreviewArea> {
-    let preview_context = context.preview_context_ref();
-    let curr_tab = context.tab_context_ref().curr_tab_ref();
+pub fn calculate_preview(
+    tab_context: &TabContext,
+    preview_context: &PreviewContext,
+    rect: Rect,
+) -> Option<PreviewArea> {
+    let curr_tab = tab_context.curr_tab_ref();
 
     let child_list = curr_tab.child_list_ref();