Vim like search (#279)

* add quick search within a list

* vim like search navigation

* close cmd line with esc

* format

* document changes in README

src/ui/listview.rs

@@ -1,4 +1,4 @@
-use std::cmp::{max, min};
+use std::cmp::{max, min, Ordering};
 use std::sync::{Arc, RwLock};
 
 use cursive::align::HAlign;
@@ -9,7 +9,7 @@ use cursive::view::ScrollBase;
 use cursive::{Cursive, Printer, Rect, Vec2};
 use unicode_width::UnicodeWidthStr;
 
-use crate::command::{Command, GotoMode, MoveAmount, MoveMode, TargetMode};
+use crate::command::{Command, GotoMode, JumpMode, MoveAmount, MoveMode, TargetMode};
 use crate::commands::CommandResult;
 use crate::library::Library;
 use crate::playable::Playable;
@@ -89,6 +89,8 @@ pub struct ListView<I: ListItem> {
     content: Arc<RwLock<Vec<I>>>,
     last_content_len: usize,
     selected: usize,
+    search_indexes: Vec<usize>,
+    search_selected_index: usize,
     last_size: Vec2,
     scrollbar: ScrollBase,
     queue: Arc<Queue>,
@@ -102,6 +104,8 @@ impl<I: ListItem> ListView<I> {
             content,
             last_content_len: 0,
             selected: 0,
+            search_indexes: Vec::new(),
+            search_selected_index: 0,
             last_size: Vec2::new(0, 0),
             scrollbar: ScrollBase::new(),
             queue,
@@ -132,6 +136,20 @@ impl<I: ListItem> ListView<I> {
         self.selected
     }
 
+    pub fn get_indexes_of(&self, query: &String) -> Vec<usize> {
+        let content = self.content.read().unwrap();
+        content
+            .iter()
+            .enumerate()
+            .filter(|(_, i)| {
+                i.display_left()
+                    .to_lowercase()
+                    .contains(&query[..].to_lowercase())
+            })
+            .map(|(i, _)| i)
+            .collect()
+    }
+
     pub fn move_focus_to(&mut self, target: usize) {
         let len = self.content.read().unwrap().len().saturating_sub(1);
         self.selected = min(target, len);
@@ -395,6 +413,47 @@ impl<I: ListItem + Clone> ViewExt for ListView<I> {
 
                 return Ok(CommandResult::Consumed(None));
             }
+            Command::Jump(mode) => match mode {
+                JumpMode::Query(query) => {
+                    self.search_indexes = self.get_indexes_of(query);
+                    self.search_selected_index = 0;
+                    match self.search_indexes.get(0) {
+                        Some(&index) => {
+                            self.move_focus_to(index);
+                            return Ok(CommandResult::Consumed(None));
+                        }
+                        None => return Ok(CommandResult::Ignored),
+                    }
+                }
+                JumpMode::Next => {
+                    let len = self.search_indexes.len();
+                    if len == 0 {
+                        return Ok(CommandResult::Ignored);
+                    }
+                    let index = self.search_selected_index;
+                    let next_index = match index.cmp(&(len - 1)) {
+                        Ordering::Equal => 0,
+                        _ => index + 1,
+                    };
+                    self.move_focus_to(self.search_indexes[next_index]);
+                    self.search_selected_index = next_index;
+                    return Ok(CommandResult::Consumed(None));
+                }
+                JumpMode::Previous => {
+                    let len = self.search_indexes.len();
+                    if len == 0 {
+                        return Ok(CommandResult::Ignored);
+                    }
+                    let index = self.search_selected_index;
+                    let prev_index = match index.cmp(&0) {
+                        Ordering::Equal => len - 1,
+                        _ => index - 1,
+                    };
+                    self.move_focus_to(self.search_indexes[prev_index]);
+                    self.search_selected_index = prev_index;
+                    return Ok(CommandResult::Consumed(None));
+                }
+            },
             Command::Move(mode, amount) => {
                 let last_idx = self.content.read().unwrap().len().saturating_sub(1);