Add Table widget base implementation

src/widgets/table.rs

@@ -0,0 +1,104 @@
+use std::cmp::max;
+
+use unicode_width::UnicodeWidthStr;
+
+use buffer::Buffer;
+use widgets::{Widget, Block};
+use layout::Rect;
+use style::Color;
+
+pub struct Table<'a> {
+    block: Option<Block<'a>>,
+    titles: &'a [&'a str],
+    widths: &'a [u16],
+    rows: &'a [&'a [&'a str]],
+    column_spacing: u16,
+}
+
+impl<'a> Default for Table<'a> {
+    fn default() -> Table<'a> {
+        Table {
+            block: None,
+            titles: &[],
+            widths: &[],
+            rows: &[],
+            column_spacing: 1,
+        }
+    }
+}
+
+impl<'a> Table<'a> {
+    pub fn block(&'a mut self, block: Block<'a>) -> &mut Table<'a> {
+        self.block = Some(block);
+        self
+    }
+
+    pub fn titles(&mut self, titles: &'a [&'a str]) -> &mut Table<'a> {
+        self.titles = titles;
+        self
+    }
+
+    pub fn widths(&mut self, widths: &'a [u16]) -> &mut Table<'a> {
+        self.widths = widths;
+        self
+    }
+
+    pub fn rows(&mut self, rows: &'a [&'a [&'a str]]) -> &mut Table<'a> {
+        self.rows = rows;
+        self
+    }
+
+    pub fn column_spacing(&mut self, spacing: u16) -> &mut Table<'a> {
+        self.column_spacing = spacing;
+        self
+    }
+}
+
+impl<'a> Widget for Table<'a> {
+    fn buffer(&self, area: &Rect, buf: &mut Buffer) {
+        let table_area = match self.block {
+            Some(ref b) => {
+                b.buffer(area, buf);
+                b.inner(area)
+            }
+            None => *area,
+        };
+
+        let mut x = 0;
+        let mut widths = Vec::with_capacity(self.widths.len());
+        for (width, title) in self.widths.iter().zip(self.titles.iter()) {
+            let w = max(title.width() as u16, *width);
+            if x + w < table_area.width {
+                widths.push(w);
+            }
+            x += w;
+        }
+
+        let mut y = table_area.top();
+
+        if y < table_area.bottom() {
+            x = table_area.left();
+            for (w, t) in widths.iter().zip(self.titles.iter()) {
+                buf.set_string(x, y, t, Color::Reset, Color::Reset);
+                x += *w + self.column_spacing;
+            }
+        }
+        y += 2;
+
+        if y < table_area.bottom() {
+            let remaining = (table_area.bottom() - y) as usize;
+            for (i, row) in self.rows.iter().take(remaining).enumerate() {
+                x = table_area.left();
+                for (w, elt) in widths.iter().zip(row.iter()) {
+                    buf.set_stringn(x,
+                                    y + i as u16,
+                                    elt,
+                                    *w as usize,
+                                    Color::Reset,
+                                    Color::Reset);
+                    x += *w + self.column_spacing;
+                }
+            }
+        }
+    }
+}