window: add print method

Add a print method with multiple print options

Signed-off-by: Tim Culverhouse <tim@timculverhouse.com>

src/Window.zig

@@ -108,10 +108,57 @@ pub fn showCursor(self: Window, col: usize, row: usize) void {
     self.screen.cursor_col = col + self.x_off;
 }
 
-/// prints text in the window with simple word wrapping.
+/// Options to use when printing Segments to a window
-pub fn wrap(self: Window, segments: []Segment) !void {
+pub const PrintOptions = struct {
-    // pub fn wrap(self: Window, str: []const u8) !void {
+    /// vertical offset to start printing at
-    var row: usize = 0;
+    row_offset: usize = 0,
+
+    /// wrap behavior for printing
+    wrap: enum {
+        /// wrap at grapheme boundaries
+        grapheme,
+        /// wrap at word boundaries
+        word,
+        /// stop printing after one line
+        none,
+    } = .grapheme,
+};
+
+/// prints segments to the window. returns true if the text overflowed with the
+/// given wrap strategy and size.
+pub fn print(self: Window, segments: []Segment, opts: PrintOptions) !bool {
+    var row = opts.row_offset;
+    switch (opts.wrap) {
+        .grapheme => {
+            var col: usize = 0;
+            for (segments) |segment| {
+                var iter = GraphemeIterator.init(segment.text);
+                while (iter.next()) |grapheme| {
+                    if (col >= self.width) {
+                        row += 1;
+                        col = 0;
+                    }
+                    if (row >= self.height) return true;
+                    const s = grapheme.slice(segment.text);
+                    if (std.mem.eql(u8, s, "\n")) {
+                        row += 1;
+                        col = 0;
+                        continue;
+                    }
+                    const w = self.gwidth(s);
+                    self.writeCell(col, row, .{
+                        .char = .{
+                            .grapheme = s,
+                            .width = w,
+                        },
+                        .style = segment.style,
+                        .link = segment.link,
+                    });
+                    col += w;
+                }
+            }
+        },
+        .word => {
             var col: usize = 0;
             var wrapped: bool = false;
             for (segments) |segment| {
@@ -132,6 +179,7 @@ pub fn wrap(self: Window, segments: []Segment) !void {
                         col = 0;
                         wrapped = true;
                     }
+                    if (row >= self.height) return true;
                     // don't print whitespace in the first column, unless we had a hard
                     // break
                     if (col == 0 and std.mem.eql(u8, word.bytes, " ") and wrapped) continue;
@@ -156,6 +204,35 @@ pub fn wrap(self: Window, segments: []Segment) !void {
                     }
                 }
             }
+        },
+        .none => {
+            var col: usize = 0;
+            for (segments) |segment| {
+                var iter = GraphemeIterator.init(segment.text);
+                while (iter.next()) |grapheme| {
+                    if (col >= self.width) return true;
+                    const s = grapheme.slice(segment.text);
+                    if (std.mem.eql(u8, s, "\n")) return true;
+                    const w = self.gwidth(s);
+                    self.writeCell(col, row, .{
+                        .char = .{
+                            .grapheme = s,
+                            .width = w,
+                        },
+                        .style = segment.style,
+                        .link = segment.link,
+                    });
+                    col += w;
+                }
+            }
+        },
+    }
+    return false;
+}
+
+/// prints text in the window with simple word wrapping.
+pub fn wrap(self: Window, segments: []Segment) !void {
+    return self.print(segments, .{ .wrap = .word });
 }
 
 test "Window size set" {