Prototype tab complete ui

src/completion.rs

@@ -0,0 +1,61 @@
+use std::{error::Error, io};
+use tui::{
+    layout::{Constraint, Corner, Direction, Layout},
+    style::{Color, Modifier, Style},
+    text::{Span, Spans},
+    widgets::{Block, Borders, List, ListItem, ListState},
+    Terminal,
+};
+
+pub struct CompletionList {
+    pub state: ListState,
+    pub items: Vec<String>,
+}
+
+impl CompletionList {
+    pub fn new() -> CompletionList {
+        CompletionList {
+            state: ListState::default(),
+            items: Vec::new(),
+        }
+    }
+
+    pub fn with_items(items: Vec<String>) -> CompletionList {
+        CompletionList {
+            state: ListState::default(),
+            items,
+        }
+    }
+
+    pub fn next(&mut self) {
+        let i = match self.state.selected() {
+            Some(i) => {
+                if i >= self.items.len() - 1 {
+                    0
+                } else {
+                    i + 1
+                }
+            }
+            None => 0,
+        };
+        self.state.select(Some(i));
+    }
+
+    pub fn previous(&mut self) {
+        let i = match self.state.selected() {
+            Some(i) => {
+                if i == 0 {
+                    self.items.len() - 1
+                } else {
+                    i - 1
+                }
+            }
+            None => 0,
+        };
+        self.state.select(Some(i));
+    }
+
+    pub fn unselect(&mut self) {
+        self.state.select(None);
+    }
+}