1 files changed, 175 insertions, 0 deletions
diff --git a/examples/go-dashboard/src/github.com/mum4k/termdash/container/draw.go b/examples/go-dashboard/src/github.com/mum4k/termdash/container/draw.go
new file mode 100644
index 000000000..d186b1272
--- /dev/null
+++ b/examples/go-dashboard/src/github.com/mum4k/termdash/container/draw.go
@@ -0,0 +1,175 @@
+// Copyright 2018 Google Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package container
+
+// draw.go contains logic to draw containers and the contained widgets.
+
+import (
+	"errors"
+	"fmt"
+	"image"
+
+	"github.com/mum4k/termdash/cell"
+	"github.com/mum4k/termdash/private/area"
+	"github.com/mum4k/termdash/private/canvas"
+	"github.com/mum4k/termdash/private/draw"
+	"github.com/mum4k/termdash/widgetapi"
+)
+
+// drawTree draws this container and all of its sub containers.
+func drawTree(c *Container) error {
+	var errStr string
+
+	root := rootCont(c)
+	size := root.term.Size()
+	ar, err := root.opts.margin.apply(image.Rect(0, 0, size.X, size.Y))
+	if err != nil {
+		return err
+	}
+	root.area = ar
+
+	preOrder(root, &errStr, visitFunc(func(c *Container) error {
+		first, second, err := c.split()
+		if err != nil {
+			return err
+		}
+		if c.first != nil {
+			ar, err := c.first.opts.margin.apply(first)
+			if err != nil {
+				return err
+			}
+			c.first.area = ar
+		}
+
+		if c.second != nil {
+			ar, err := c.second.opts.margin.apply(second)
+			if err != nil {
+				return err
+			}
+			c.second.area = ar
+		}
+		return drawCont(c)
+	}))
+	if errStr != "" {
+		return errors.New(errStr)
+	}
+	return nil
+}
+
+// drawBorder draws the border around the container if requested.
+func drawBorder(c *Container) error {
+	if !c.hasBorder() {
+		return nil
+	}
+
+	cvs, err := canvas.New(c.area)
+	if err != nil {
+		return err
+	}
+
+	ar, err := area.FromSize(cvs.Size())
+	if err != nil {
+		return err
+	}
+
+	var cOpts []cell.Option
+	if c.focusTracker.isActive(c) {
+		cOpts = append(cOpts, cell.FgColor(c.opts.inherited.focusedColor))
+	} else {
+		cOpts = append(cOpts, cell.FgColor(c.opts.inherited.borderColor))
+	}
+
+	if err := draw.Border(cvs, ar,
+		draw.BorderLineStyle(c.opts.border),
+		draw.BorderTitle(c.opts.borderTitle, draw.OverrunModeThreeDot, cOpts...),
+		draw.BorderTitleAlign(c.opts.borderTitleHAlign),
+		draw.BorderCellOpts(cOpts...),
+	); err != nil {
+		return err
+	}
+	return cvs.Apply(c.term)
+}
+
+// drawWidget requests the widget to draw on the canvas.
+func drawWidget(c *Container) error {
+	widgetArea, err := c.widgetArea()
+	if err != nil {
+		return err
+	}
+	if widgetArea == image.ZR {
+		return nil
+	}
+
+	if !c.hasWidget() {
+		return nil
+	}
+
+	needSize := image.Point{1, 1}
+	wOpts := c.opts.widget.Options()
+	if wOpts.MinimumSize.X > 0 && wOpts.MinimumSize.Y > 0 {
+		needSize = wOpts.MinimumSize
+	}
+
+	if widgetArea.Dx() < needSize.X || widgetArea.Dy() < needSize.Y {
+		return drawResize(c, c.usable())
+	}
+
+	cvs, err := canvas.New(widgetArea)
+	if err != nil {
+		return err
+	}
+
+	meta := &widgetapi.Meta{
+		Focused: c.focusTracker.isActive(c),
+	}
+
+	if err := c.opts.widget.Draw(cvs, meta); err != nil {
+		return err
+	}
+	return cvs.Apply(c.term)
+}
+
+// drawResize draws an unicode character indicating that the size is too small to draw this container.
+// Does nothing if the size is smaller than one cell, leaving no space for the character.
+func drawResize(c *Container, area image.Rectangle) error {
+	if area.Dx() < 1 || area.Dy() < 1 {
+		return nil
+	}
+
+	cvs, err := canvas.New(area)
+	if err != nil {
+		return err
+	}
+	if err := draw.ResizeNeeded(cvs); err != nil {
+		return err
+	}
+	return cvs.Apply(c.term)
+}
+
+// drawCont draws the container and its widget.
+func drawCont(c *Container) error {
+	if us := c.usable(); us.Dx() <= 0 || us.Dy() <= 0 {
+		return drawResize(c, c.area)
+	}
+
+	if err := drawBorder(c); err != nil {
+		return fmt.Errorf("unable to draw container border: %v", err)
+	}
+
+	if err := drawWidget(c); err != nil {
+		return fmt.Errorf("unable to draw widget %T: %v", c.opts.widget, err)
+	}
+	return nil
+}