Extending PromptMode (#74)

* Revamp Prompt states

The idea here is that what we want to display on the screen which can
impact the prompt should be available as part of the prompt's interface.

So here are the things that can impact what we show with our prompt
- The line-editor can either be in Emacs mode or VI mode (for now)
  [These are exclusive to one another]
- The line-editor can be either in editing a command or searching
  history mode [These two states are also exclusive]
- Lastly the command can be either single-line or multi-line.

Now all these variables can happen togeter (i.e. they for a cross
prodcut)
- example 1: You can be in vi-normal mode and be editing history search
  term and that particular term earlier resulted in a multi-line
  command. (So, we need to showcase all these three variations together)

one way to do this is using a struct. I found that it was making the
more frequent case (of being in edit mode) overly complex so I chose to
expose the functionality as separate methonds.

* Cleanup custom strings from engine

src/engine.rs

@@ -2,7 +2,7 @@ use crate::{
     clip_buffer::{get_default_clipboard, Clipboard},
     default_emacs_keybindings,
     keybindings::{default_vi_insert_keybindings, default_vi_normal_keybindings, Keybindings},
-    prompt::PromptMode,
+    prompt::{PromptEditMode, PromptHistorySearch, PromptHistorySearchStatus, PromptViMode},
     DefaultPrompt, Prompt,
 };
 use crate::{history::History, line_buffer::LineBuffer};
@@ -147,10 +147,11 @@ impl Reedline {
         self.edit_mode
     }
 
-    pub fn prompt_mode(&self) -> PromptMode {
+    pub fn prompt_edit_mode(&self) -> PromptEditMode {
         match self.edit_mode {
-            EditMode::ViInsert => PromptMode::ViInsert,
-            _ => PromptMode::Normal,
+            EditMode::ViInsert => PromptEditMode::Vi(PromptViMode::Insert),
+            EditMode::ViNormal => PromptEditMode::Vi(PromptViMode::Normal),
+            EditMode::Emacs => PromptEditMode::Emacs,
         }
     }
 
@@ -636,7 +637,7 @@ impl Reedline {
     /// Used at the beginning of each [`Reedline::read_line()`] call.
     fn queue_prompt(&mut self, screen_width: usize) -> Result<()> {
         // print our prompt
-        let prompt_mode = self.prompt_mode();
+        let prompt_mode = self.prompt_edit_mode();
 
         self.stdout
             .queue(MoveToColumn(0))?
@@ -654,7 +655,7 @@ impl Reedline {
     /// the prompt
     fn queue_prompt_indicator(&mut self) -> Result<()> {
         // print our prompt
-        let prompt_mode = self.prompt_mode();
+        let prompt_mode = self.prompt_edit_mode();
         self.stdout
             .queue(MoveToColumn(0))?
             .queue(SetForegroundColor(self.prompt.get_prompt_color()))?
@@ -724,19 +725,21 @@ impl Reedline {
             .expect("couldn't get history_search reference");
 
         let status = if search.result.is_none() && !search.search_string.is_empty() {
-            "failed "
+            PromptHistorySearchStatus::Failing
         } else {
-            ""
+            PromptHistorySearchStatus::Passing
         };
 
+        let prompt_history_search = PromptHistorySearch::new(status, search.search_string.clone());
+        let history_indicator = self
+            .prompt
+            .render_prompt_history_search_indicator(prompt_history_search);
+
         // print search prompt
         self.stdout
             .queue(MoveToColumn(0))?
             .queue(SetForegroundColor(Color::Blue))?
-            .queue(Print(format!(
-                "({}reverse-search)`{}':",
-                status, search.search_string
-            )))?
+            .queue(Print(history_indicator))?
             .queue(ResetColor)?;
 
         match search.result {

src/prompt.rs

@@ -5,13 +5,39 @@ use std::env;
 pub static DEFAULT_PROMPT_COLOR: Color = Color::Blue;
 pub static DEFAULT_PROMPT_INDICATOR: &str = "〉";
 pub static DEFAULT_VI_INSERT_PROMPT_INDICATOR: &str = ": ";
+pub static DEFAULT_VI_VISUAL_PROMPT_INDICATOR: &str = "v ";
 pub static DEFAULT_MULTILINE_INDICATOR: &str = "::: ";
 
-/// The type of prompt indicator to display
-pub enum PromptMode {
+pub enum PromptHistorySearchStatus {
+    Passing,
+    Failing,
+}
+
+pub struct PromptHistorySearch {
+    status: PromptHistorySearchStatus,
+    term: String,
+}
+
+impl PromptHistorySearch {
+    pub fn new(status: PromptHistorySearchStatus, search_term: String) -> Self {
+        PromptHistorySearch {
+            status,
+            term: search_term,
+        }
+    }
+}
+
+pub enum PromptEditMode {
+    Default,
+    Emacs,
+    Vi(PromptViMode),
+    Custom(String),
+}
+
+pub enum PromptViMode {
     Normal,
-    ViInsert,
-    Multiline,
+    Insert,
+    Visual,
 }
 
 /// API to provide a custom prompt.
@@ -22,7 +48,12 @@ pub trait Prompt {
     /// Provide content off the full prompt. May use a line above the entry buffer that fits into `screen_width`.
     fn render_prompt(&self, screen_width: usize) -> String;
     /// Render the default prompt indicator
-    fn render_prompt_indicator(&self, prompt_mode: PromptMode) -> String;
+    fn render_prompt_indicator(&self, prompt_mode: PromptEditMode) -> String;
+    /// Render the default prompt indicator
+    fn render_prompt_multiline_indicator(&self) -> String;
+    /// Render the default prompt indicator
+    fn render_prompt_history_search_indicator(&self, history_search: PromptHistorySearch)
+        -> String;
     /// Render the vi insert mode prompt indicator
     /// Get back the prompt color
     fn get_prompt_color(&self) -> Color {
@@ -35,13 +66,35 @@ impl Prompt for DefaultPrompt {
         DefaultPrompt::render_prompt(self, screen_width)
     }
 
-    fn render_prompt_indicator(&self, prompt_mode: PromptMode) -> String {
-        match prompt_mode {
-            PromptMode::Normal => DEFAULT_PROMPT_INDICATOR.into(),
-            PromptMode::ViInsert => DEFAULT_VI_INSERT_PROMPT_INDICATOR.into(),
-            PromptMode::Multiline => DEFAULT_MULTILINE_INDICATOR.into(),
+    fn render_prompt_indicator(&self, edit_mode: PromptEditMode) -> String {
+        match edit_mode {
+            PromptEditMode::Default => DEFAULT_PROMPT_INDICATOR.into(),
+            PromptEditMode::Emacs => DEFAULT_PROMPT_INDICATOR.into(),
+            PromptEditMode::Vi(vi_mode) => match vi_mode {
+                PromptViMode::Normal => DEFAULT_PROMPT_INDICATOR.into(),
+                PromptViMode::Insert => DEFAULT_VI_INSERT_PROMPT_INDICATOR.into(),
+                PromptViMode::Visual => DEFAULT_VI_VISUAL_PROMPT_INDICATOR.into(),
+            },
+            PromptEditMode::Custom(str) => self.default_wrapped_custom_string(str),
         }
     }
+
+    fn render_prompt_multiline_indicator(&self) -> String {
+        DEFAULT_MULTILINE_INDICATOR.into()
+    }
+
+    fn render_prompt_history_search_indicator(
+        &self,
+        history_search: PromptHistorySearch,
+    ) -> String {
+        let prefix = match history_search.status {
+            PromptHistorySearchStatus::Passing => "",
+            PromptHistorySearchStatus::Failing => "failing ",
+        };
+        // NOTE: magic strings, givent there is logic on how these compose I am not sure if it
+        // is worth extracting in to static constant
+        format!("({}reverse-search: {})", prefix, history_search.term)
+    }
 }
 
 impl Default for DefaultPrompt {
@@ -90,6 +143,10 @@ impl DefaultPrompt {
 
         prompt_str
     }
+
+    fn default_wrapped_custom_string(&self, str: String) -> String {
+        format!("({})", str)
+    }
 }
 
 fn get_working_dir() -> Result<String, std::io::Error> {