feat: draw info on number of candidates

Draws the [filtered] / [total] candidate information in the query line. The counts are right-aligned and are hidden if the prompt extends past the beginning of the numbers. This commit also tidies up the drawing function with better organization and prevents the query line from wrapping.
natecraddock · Feb 27, 2022 · 6aa45e3 · 6aa45e3
1 parent ae0d598
commit 6aa45e3
Showing 1 changed file with 33 additions and 10 deletions.
diff --git a/src/ui.zig b/src/ui.zig
@@ -66,7 +66,7 @@ pub const Terminal = struct {
     }
 
     pub fn clearLine(self: *Terminal) void {
-        self.write(.{ 0, 'G' });
+        self.cursorCol(1);
         self.write(.{ 2, 'K' });
     }
 
@@ -85,6 +85,18 @@ pub const Terminal = struct {
         self.write(.{ num, 'B' });
     }
 
+    pub fn cursorRight(self: *Terminal, num: usize) void {
+        self.write(.{ num, 'C' });
+    }
+
+    pub fn cursorLeft(self: *Terminal, num: usize) void {
+        self.write(.{ num, 'D' });
+    }
+
+    pub fn cursorCol(self: *Terminal, col: usize) void {
+        self.write(.{ col, 'G' });
+    }
+
     pub fn sgr(self: *Terminal, code: Attribute) void {
         self.write(.{ @enumToInt(code), 'm' });
     }
@@ -190,7 +202,12 @@ inline fn drawCandidate(terminal: *Terminal, candidate: Candidate, width: usize,
     terminal.sgr(.RESET);
 }
 
-fn draw(terminal: *Terminal, state: *State, query: ArrayList(u8), candidates: []Candidate) !void {
+inline fn numDigits(number: usize) u16 {
+    if (number == 0) return 1;
+    return @intCast(u16, std.math.log10(number) + 1);
+}
+
+fn draw(terminal: *Terminal, state: *State, query: ArrayList(u8), candidates: []Candidate, total_candidates: usize) !void {
     const width = terminal.windowSize().?.x;
 
     // draw the candidates
@@ -205,14 +222,20 @@ fn draw(terminal: *Terminal, state: *State, query: ArrayList(u8), candidates: []
 
     // draw the prompt
     terminal.clearLine();
-    try terminal.writer.print("> {s}\r", .{query.items});
-
-    // move cursor by drawing chars
-    _ = try terminal.writer.write("> ");
-    for (query.items) |c, index| {
-        if (index == state.cursor) break;
-        _ = try terminal.writer.writeByte(c);
+    try terminal.writer.print("> {s}", .{query.items[0..std.math.min(width - 2, query.items.len)]});
+
+    // draw info if there is room
+    const prompt_width = 2;
+    const separator_width = 1;
+    const spacing = @intCast(i32, width) - @intCast(i32, prompt_width + query.items.len + numDigits(candidates.len) + numDigits(total_candidates) + separator_width);
+    if (spacing >= 1) {
+        terminal.cursorRight(@intCast(usize, spacing));
+        try terminal.writer.print("{}/{}", .{ candidates.len, total_candidates });
     }
+
+    // position the cursor at the edit location
+    terminal.cursorCol(1);
+    terminal.cursorRight(std.math.min(width - 1, state.cursor + 2));
 }
 
 const Action = union(enum) {
@@ -333,7 +356,7 @@ pub fn run(
         // did the selection move?
         if (redraw or state.cursor != old_state.cursor or state.selected != old_state.selected) {
             old_state = state;
-            try draw(terminal, &state, query, filtered);
+            try draw(terminal, &state, query, filtered, candidates.len);
             redraw = false;
         }