Command mode feature

* Add vim like command mode

* Colon now enters command mode
* Added a modal approach kept track of in Program struct
    Current modes: normal, command, exit
* Changed previous fn run -> fn run_normal_mode
* Add basis for future command mode commands

* Add cmd mode for infobar, cmd mode help and quit

* Modified infobar so that it takes a &str called msg in the case of
    command mode displays what the user is currently typing
* Add :help to print the help message and return to normal mode
* Add :quit to terminate the program from command mode

Command mode is any mode that requires user input

 * Moved command_mode related functions into its own file
 * Command Mode Features:
    * newglob (takes only one paramter). Properly handles ~/$HOME when
	provided by user. When the current path exists in the current vec of images
	and in the future one, remain at its index

    * sort (optionally one paramter). if called alone just performs the
	selected sort on the images, if provided with a second argument (a
	SortOrder) switch to that then sort. User is moved to new index
	of current image prior to sort

    * reverse, reverses the current set of images, keeping the index of
	the current image

    * destfolder, sets the destination folder

    * help, exits command mode and displays help info in normal mode

    * quit, terminates program

Increased performance, inside command_mode function get_command by not
rendering user input ever event, but only when it changes

* Add dependency shellexpand to properly handle ~/$HOME/env vars

* Add Mode, Error, to display error messages
* ui.rs Mode variants now take Strings if they need to display on infobar

* sdl2 text_input is used to handle keys like 'j','k', 'q', etc
* changed help to '?' instead of 'h'

* Updated README with Command mode options

* Now properly handles env vars and ~

* Entering command mode toggles bar on by default

* Paths::current_dir -> base_dir, better track of df

* Changes to dest_folder is now kept track for the case
of newglob to maintain the invariant that if the user hasn't set dest
folder, images should be moved to "./keep" by default unless specified
otherwise

Cargo.toml

@@ -9,6 +9,7 @@ clap = "2.33"
 glob = "0.3"
 fs_extra = "1.1"
 natord = "1.0.9"
+shellexpand = "1.0"
 
 [dependencies.sdl2]
 version = "0.32"

README.md

@@ -49,7 +49,7 @@ Set the maximum number of images to be displayed `m` or `--max` flag. 0 means in
 
 ```$ riv -m 0 **/*.png```
 
-### Controls
+### Normal Mode Controls
 
 
 | Key              | Action                                                 |
@@ -70,6 +70,19 @@ Set the maximum number of images to be displayed `m` or `--max` flag. 0 means in
 | z OR Left Click  | Toggle actual size vs scaled image                     |
 | . (period)       | Repeat last action                                     |
 
+### Command Mode Controls
+
+
+| Command                     | Action                                                   |
+|-----------------------------|----------------------------------------------------------|
+| ng OR newglob [glob]        | **Required argument** the new glob/directory/file        |
+| ? OR help                   | Toggle fullscreen mode                                   |
+| q OR quit                   | Quit                                                     |
+| sort (method)               | *Optional argument* the new method to sort by            |
+| df OR destfolder [path]     | **Required argument** new folder to move/copy images to  |
+| m OR max [positive integer] | **Required argument** new maximum number of files to view|
+
+
 ## Getting Started
 
 These instructions will get you a copy of the project up and running on your local machine for development and testing purposes.

src/cli.rs

@@ -124,7 +124,7 @@ pub fn cli() -> Result<Args, String> {
     })
 }
 
-fn push_image_path(v: &mut Vec<PathBuf>, p: PathBuf) {
+pub(crate) fn push_image_path(v: &mut Vec<PathBuf>, p: PathBuf) {
     if let Some(ext) = p.extension() {
         if let Some(ext_str) = ext.to_str() {
             let low = ext_str.to_string().to_lowercase();

src/infobar.rs

@@ -3,32 +3,52 @@
 //! Module InfoBar provides structures and functions for building and rendering an infobar
 
 use crate::paths::Paths;
+use crate::ui::Mode;
 
 /// Text contains the strings required to print the infobar.
 pub struct Text {
-    /// current image is the string of the current image path
-    pub current_image: String,
-    /// index is the string represention of the index.
-    pub index: String,
+    /// Either displays the name of the current image or the current command the user is typing in
+    /// command mode
+    pub information: String,
+    /// In normal mode this is the string represention of the index, in command mode this is
+    /// "Command"
+    pub mode: String,
 }
 
-impl From<&Paths> for Text {
-    fn from(p: &Paths) -> Self {
-        let current_image = match p.images.get(p.index) {
-            Some(path) => match path.to_str() {
-                Some(name) => name.to_string(),
-                None => "No file".to_string(),
-            },
-            None => "No file selected".to_string(),
+impl Text {
+    /// Updates the infobar based on the current mode of the applicaiton
+    /// Normal Mode:
+    ///     mode = index of current image
+    ///     information = path to current image
+    /// Command Mode:
+    ///     mode = "Command"
+    ///     information = curerntly entered user string
+    /// Error Mode:
+    ///     mode = "Error"
+    ///     information = error message to display
+    pub fn update(current_mode: &Mode, paths: &Paths) -> Self {
+        let (mode, information) = match current_mode {
+            Mode::Command(msg) => ("Command".to_string(), format!(":{}", msg)),
+            Mode::Normal => {
+                let information: String;
+                let mode: String;
+                information = match paths.images.get(paths.index) {
+                    Some(path) => match path.to_str() {
+                        Some(name) => name.to_string(),
+                        None => "No file".to_string(),
+                    },
+                    None => "No file selected".to_string(),
+                };
+                mode = if paths.images.is_empty() {
+                    "No files in path".to_string()
+                } else {
+                    format!("{} of {}", paths.index + 1, paths.max_viewable)
+                };
+                (mode, information)
+            }
+            Mode::Error(msg) => ("Error".to_string(), msg.to_string()),
+            _ => ("Exit".to_string(), "Exiting... Goodbye".to_string()),
         };
-        let index = if p.images.is_empty() {
-            "No files in path".to_string()
-        } else {
-            format!("{} of {}", p.index + 1, p.max_viewable)
-        };
-        Text {
-            current_image,
-            index,
-        }
+        Text { information, mode }
     }
 }

src/paths.rs

@@ -9,10 +9,14 @@ pub struct Paths {
     pub images: Vec<PathBuf>,
     /// dest_folder is the path of the destination folder for moving and copying images.
     pub dest_folder: PathBuf,
+    /// dest_folder was modified from the default keep through Command mode df or destfolder
+    pub changed_dest_folder: bool,
     /// current_dir is the path of the current directory where the program was launched from
-    pub current_dir: PathBuf,
+    pub base_dir: PathBuf,
     /// index is the index of the images vector of the current image to be displayed.
     pub index: usize,
     /// Artificial user facing length of images limited by max cli argument
     pub max_viewable: usize,
+    /// Actual length the user said was maximum for images
+    pub actual_max_viewable: usize,
 }