From b909cd45598c14b3685e20b4d0b0d6d3c20e2db5 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Maxime=20=E2=80=9Cpep=E2=80=9D=20Buquet?= <pep@bouah.net>
Date: Fri, 21 Apr 2023 12:46:57 +0200
Subject: [PATCH] WIP: InputMode::{Normal, Input}
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Content-Type: text/plain; charset=UTF-8
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Signed-off-by: Maxime “pep” Buquet <pep@bouah.net>
---
 src/input.rs | 43 ++++++++++++++++++++++++++++++++++++++++++-
 src/main.rs  |  1 +
 2 files changed, 43 insertions(+), 1 deletion(-)

diff --git a/src/input.rs b/src/input.rs
index b8cd089..78f798b 100644
--- a/src/input.rs
+++ b/src/input.rs
@@ -9,14 +9,26 @@ use unicode_width::{UnicodeWidthChar, UnicodeWidthStr};
 // TODO: add punctuation.
 const SEPARATORS: [char; 3] = [' ', '\t', '\n'];
 
+#[derive(Debug, PartialEq)]
+pub enum InputMode {
+    /// Insert mode. For inserting new text.
+    Insert,
+
+    /// Normal mode. For navigation and manipulation of text. Use Escape to come back to Normal
+    /// mode from any other mode.
+    Normal,
+}
+
 #[derive(Debug)]
 pub enum InputEvent {
     None,
     Exit,
     Text(String),
+    Mode(InputMode),
 }
 
 pub struct Input<W: Write> {
+    mode: InputMode,
     stdout: W,
     string: Vec<char>,
     clipboard: Vec<char>,
@@ -27,6 +39,7 @@ pub struct Input<W: Write> {
 impl<W: Write> Input<W> {
     pub fn new(stdout: W) -> Input<W> {
         Input {
+            mode: InputMode::Insert,
             stdout,
             string: Vec::new(),
             clipboard: Vec::new(),
@@ -35,10 +48,15 @@ impl<W: Write> Input<W> {
         }
     }
 
+    pub fn with_mode(&mut self, mode: InputMode) {
+        self.mode = mode
+    }
+
     #[cfg(test)]
     fn from(stdout: W, input: &str) -> Input<W> {
         let string: Vec<char> = input.chars().collect();
         Input {
+            mode: InputMode::Insert,
             stdout,
             cursor: string.len(),
             string,
@@ -73,8 +91,19 @@ impl<W: Write> Input<W> {
     }
 
     pub fn handle_key(&mut self, code: KeyCode, modifiers: KeyModifiers) -> Result<InputEvent> {
+        // Escape always changes input mode back to Normal.
+        if let KeyCode::Esc = code {
+            return Ok(InputEvent::Mode(InputMode::Normal));
+        }
+
+        match self.mode {
+            InputMode::Insert => self.handle_key_mode_input(code, modifiers),
+            _ => Ok(InputEvent::None)
+        }
+    }
+
+    pub fn handle_key_mode_input(&mut self, code: KeyCode, modifiers: KeyModifiers) -> Result<InputEvent> {
         match (code, modifiers) {
-            (KeyCode::Esc, _) => return Ok(InputEvent::Exit),
             (KeyCode::Char('d'), KeyModifiers::CONTROL) => return Ok(InputEvent::Exit),
             (KeyCode::Char('l'), KeyModifiers::CONTROL) => {
                 self.stdout
@@ -325,4 +354,16 @@ mod test {
         }
         Ok(())
     }
+
+    #[test]
+    fn mode_change_normal() -> Result<()> {
+        let mut stdout = Vec::new();
+        let mut input = Input::new(&mut stdout);
+        let event = input.handle_key(KeyCode::Esc, KeyModifiers::NONE)?;
+        match event {
+            InputEvent::Mode(mode) => assert_eq!(mode, InputMode::Normal),
+            evt => panic!("Wrong event: {evt:?}"),
+        }
+        Ok(())
+    }
 }
diff --git a/src/main.rs b/src/main.rs
index dba1a20..bced54b 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -149,6 +149,7 @@ impl<'a> ChatTab<'a> {
                     Event::Key(event) => {
                         match self.input.handle_key(event.code, event.modifiers) {
                             Ok(InputEvent::Exit) => break,
+                            Ok(InputEvent::Mode(mode)) => self.input.with_mode(mode),
                             Ok(InputEvent::Text(message)) => {
                                 /*
                                 let item = logger::Item::Message(logger::LogMessage {