Base theming for views

- Control is now aware of active theme name and resolver.
- Theme some settings in BoxView, ListView and MenuView.
- Overhaul scenario system to make it work with themes.
- Add new "background" StyleSetting.
- Relates spring-projects#824

Author: jvalkeal

spring-shell-core/src/main/java/org/springframework/shell/component/view/control/AbstractView.java

@@ -27,13 +27,14 @@
 
 import org.springframework.lang.Nullable;
 import org.springframework.messaging.Message;
+import org.springframework.shell.component.view.control.cell.AbstractControl;
 import org.springframework.shell.component.view.event.EventLoop;
 import org.springframework.shell.component.view.event.KeyBindingConsumer;
 import org.springframework.shell.component.view.event.KeyBindingConsumerArgs;
 import org.springframework.shell.component.view.event.KeyEvent;
 import org.springframework.shell.component.view.event.KeyHandler;
-import org.springframework.shell.component.view.event.MouseBindingConsumerArgs;
 import org.springframework.shell.component.view.event.MouseBindingConsumer;
+import org.springframework.shell.component.view.event.MouseBindingConsumerArgs;
 import org.springframework.shell.component.view.event.MouseEvent;
 import org.springframework.shell.component.view.event.MouseHandler;
 import org.springframework.shell.component.view.geom.Rectangle;
@@ -46,14 +47,10 @@
  *
  * @author Janne Valkealahti
  */
-public abstract class AbstractView implements View {
+public abstract class AbstractView extends AbstractControl implements View {
 
 	private final static Logger log = LoggerFactory.getLogger(AbstractView.class);
 	private final Disposable.Composite disposables = Disposables.composite();
-	private int x = 0;
-	private int y = 0;
-	private int width = 0;
-	private int height = 0;
 	private BiFunction<Screen, Rectangle, Rectangle> drawFunction;
 	private boolean hasFocus;
 	private int layer;
@@ -99,19 +96,6 @@ protected final void init() {
 	protected void initInternal() {
 	}
 
-	@Override
-	public void setRect(int x, int y, int width, int height) {
-		this.x = x;
-		this.y = y;
-		this.width = width;
-		this.height = height;
-	}
-
-	@Override
-	public Rectangle getRect() {
-		return new Rectangle(x, y, width, height);
-	}
-
 	@Override
 	public void setLayer(int index) {
 		this.layer = index;

spring-shell-core/src/main/java/org/springframework/shell/component/view/control/AppView.java

@@ -22,6 +22,7 @@
 import org.springframework.shell.component.view.geom.Rectangle;
 import org.springframework.shell.component.view.message.ShellMessageBuilder;
 import org.springframework.shell.component.view.screen.Screen;
+import org.springframework.shell.style.ThemeResolver;
 import org.springframework.util.Assert;
 
 /**
@@ -49,6 +50,22 @@ public AppView(View main, View menuBar, View statusBar) {
 		initLayout();
 	}
 
+	@Override
+	public void setThemeName(String themeName) {
+		super.setThemeName(themeName);
+		main.setThemeName(themeName);
+		menu.setThemeName(themeName);
+		status.setThemeName(themeName);
+	}
+
+	@Override
+	public void setThemeResolver(ThemeResolver themeResolver) {
+		super.setThemeResolver(themeResolver);
+		main.setThemeResolver(themeResolver);
+		menu.setThemeResolver(themeResolver);
+		status.setThemeResolver(themeResolver);
+	}
+
 	private void initLayout() {
 		grid = new GridView();
 		grid.setRowSize(1, 0, 1);

spring-shell-core/src/main/java/org/springframework/shell/component/view/control/BoxView.java

@@ -18,11 +18,11 @@
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
-import org.springframework.lang.Nullable;
 import org.springframework.shell.component.view.geom.HorizontalAlign;
 import org.springframework.shell.component.view.geom.Rectangle;
 import org.springframework.shell.component.view.geom.VerticalAlign;
 import org.springframework.shell.component.view.screen.Screen;
+import org.springframework.shell.style.StyleSettings;
 import org.springframework.util.StringUtils;
 
 /**
@@ -45,7 +45,8 @@ public class BoxView extends AbstractView {
 	private int paddingBottom;
 	private int paddingLeft;
 	private int paddingRight;
-	private Integer backgroundColor = -1;
+	private boolean transparent = true;
+	private int backgroundColor = -1;
 	private int titleColor = -1;
 	private int titleStyle = -1;
 	private int focusedTitleColor = -1;
@@ -110,7 +111,7 @@ public void setTitle(String title) {
 	 *
 	 * @param backgroundColor the background color
 	 */
-	public void setBackgroundColor(@Nullable Integer backgroundColor) {
+	public void setBackgroundColor(int backgroundColor) {
 		this.backgroundColor = backgroundColor;
 	}
 
@@ -161,6 +162,24 @@ public void setTitleAlign(HorizontalAlign titleAlign) {
 		this.titleAlign = titleAlign;
 	}
 
+	/**
+	 * Sets if box should be transparent, {@code true} by default.
+	 *
+	 * @param transparent a transparency flag
+	 */
+	public void setTransparent(boolean transparent) {
+		this.transparent = transparent;
+	}
+
+	/**
+	 * Is box transparent.
+	 *
+	 * @return box transparency
+	 */
+	protected boolean isTransparent() {
+		return transparent;
+	}
+
 	/**
 	 * Possibly draws a box around this view and title in a box top boundary. Also
 	 * calls a {@code draw function} if defined.
@@ -173,12 +192,14 @@ protected void drawInternal(Screen screen) {
 		if (rect.width() <= 0 || rect.height() <= 0) {
 			return;
 		}
-		if (backgroundColor == null) {
-			screen.writerBuilder().layer(getLayer()).build().background(rect, -1);
+		int bgColor;
+		if (isTransparent()) {
+			bgColor = backgroundColor > -1 ? backgroundColor : -1;
 		}
-		else if (backgroundColor > -1) {
-			screen.writerBuilder().layer(getLayer()).build().background(rect, backgroundColor);
+		else {
+			bgColor = resolveThemeBackground(StyleSettings.TAG_BACKGROUND, backgroundColor, -1);
 		}
+		screen.writerBuilder().layer(getLayer()).build().background(rect, bgColor);
 		if (showBorder && rect.width() >= 2 && rect.height() >= 2) {
 			screen.writerBuilder().layer(getLayer()).build().border(rect.x(), rect.y(), rect.width(), rect.height());
 			if (StringUtils.hasText(title)) {

spring-shell-core/src/main/java/org/springframework/shell/component/view/control/Control.java

@@ -15,8 +15,10 @@
  */
 package org.springframework.shell.component.view.control;
 
+import org.springframework.lang.Nullable;
 import org.springframework.shell.component.view.geom.Rectangle;
 import org.springframework.shell.component.view.screen.Screen;
+import org.springframework.shell.style.ThemeResolver;
 
 /**
  * Base interface for all controls. {@link Control} is able to define a
@@ -51,4 +53,19 @@ public interface Control {
 	 * @param height a height of a bounded box
 	 */
 	void setRect(int x, int y, int width, int height);
+
+	/**
+	 * Sets a {@link ThemeResolver}.
+	 *
+	 * @param themeResolver the theme resolver
+	 */
+	void setThemeResolver(@Nullable ThemeResolver themeResolver);
+
+	/**
+	 * Sets a theme name to use.
+	 *
+	 * @param themeName the theme name
+	 */
+	void setThemeName(@Nullable String themeName);
+
 }

spring-shell-core/src/main/java/org/springframework/shell/component/view/control/ListView.java

@@ -26,6 +26,7 @@
 import org.springframework.shell.component.view.message.ShellMessageBuilder;
 import org.springframework.shell.component.view.screen.Screen;
 import org.springframework.shell.component.view.screen.ScreenItem;
+import org.springframework.shell.style.StyleSettings;
 
 /**
  * {@link ListView} shows {@code list items} vertically.
@@ -51,12 +52,13 @@ protected void drawInternal(Screen screen) {
 		Rectangle rect = getInnerRect();
 		int y = rect.y();
 
+		int selectedStyle = resolveThemeStyle(StyleSettings.TAG_HIGHLIGHT, ScreenItem.STYLE_BOLD);
 		int i = 0;
 		for (ListCell<T> c : cells) {
 			c.setRect(rect.x(), y++, rect.width(), 1);
 			if (i == selected) {
 				c.updateSelected(true);
-				c.setStyle(ScreenItem.STYLE_BOLD);
+				c.setStyle(selectedStyle);
 			}
 			else {
 				c.updateSelected(false);

spring-shell-core/src/main/java/org/springframework/shell/component/view/control/MenuBarView.java

@@ -35,6 +35,7 @@
 import org.springframework.shell.component.view.geom.Rectangle;
 import org.springframework.shell.component.view.screen.Screen;
 import org.springframework.shell.component.view.screen.Screen.Writer;
+import org.springframework.shell.style.ThemeResolver;
 import org.springframework.shell.component.view.screen.ScreenItem;
 
 /**
@@ -201,6 +202,18 @@ private void select(MouseEvent event) {
 		checkMenuView();
 	}
 
+	@Override
+	public void setThemeName(String themeName) {
+		super.setThemeName(themeName);
+		menuViews.values().forEach(view -> view.setThemeName(themeName));
+	}
+
+	@Override
+	public void setThemeResolver(ThemeResolver themeResolver) {
+		super.setThemeResolver(themeResolver);
+		menuViews.values().forEach(view -> view.setThemeResolver(themeResolver));
+	}
+
 	private void checkMenuView() {
 		if (activeItemIndex < 0) {
 			closeCurrentMenuView();
@@ -218,8 +231,10 @@ private void closeCurrentMenuView() {
 	private MenuView buildMenuView(MenuBarItem item) {
 		MenuView menuView = new MenuView(item.getItems());
 		menuView.setEventLoop(getEventLoop());
+		menuView.setThemeResolver(getThemeResolver());
+		menuView.setThemeName(getThemeName());
 		menuView.setShowBorder(true);
-		menuView.setBackgroundColor(null);
+		menuView.setTransparent(false);
 		menuView.setLayer(1);
 		Rectangle rect = getInnerRect();
 		int x = positionAtIndex(activeItemIndex);

spring-shell-core/src/main/java/org/springframework/shell/component/view/control/MenuView.java

@@ -33,6 +33,7 @@
 import org.springframework.shell.component.view.message.ShellMessageBuilder;
 import org.springframework.shell.component.view.screen.Screen;
 import org.springframework.shell.component.view.screen.Screen.Writer;
+import org.springframework.shell.style.StyleSettings;
 import org.springframework.shell.component.view.screen.ScreenItem;
 import org.springframework.util.Assert;
 import org.springframework.util.StringUtils;
@@ -143,7 +144,8 @@ protected void drawInternal(Screen screen) {
 		Rectangle rect = getInnerRect();
 		int y = rect.y();
 		Writer writer = screen.writerBuilder().layer(getLayer()).build();
-		Writer writer2 = screen.writerBuilder().layer(getLayer()).style(ScreenItem.STYLE_BOLD).build();
+		int themeStyle = resolveThemeStyle(StyleSettings.TAG_HIGHLIGHT, ScreenItem.STYLE_BOLD);
+		Writer writer2 = screen.writerBuilder().layer(getLayer()).style(themeStyle).build();
 		int i = 0;
 		boolean hasCheck = false;
 		for (MenuItem item : items) {

spring-shell-core/src/main/java/org/springframework/shell/component/view/control/cell/AbstractControl.java

@@ -15,8 +15,15 @@
  */
 package org.springframework.shell.component.view.control.cell;
 
+import java.util.Optional;
+
+import org.jline.utils.AttributedStyle;
+
+import org.springframework.lang.Nullable;
 import org.springframework.shell.component.view.control.Control;
 import org.springframework.shell.component.view.geom.Rectangle;
+import org.springframework.shell.style.ThemeResolver;
+import org.springframework.shell.style.ThemeResolver.ResolvedValues;
 
 /**
  * Base implementation of a {@link Control}.
@@ -29,6 +36,8 @@ public abstract class AbstractControl implements Control {
 	private int y = 0;
 	private int width = 0;
 	private int height = 0;
+	private ThemeResolver themeResolver;
+	private String themeName;
 
 	@Override
 	public void setRect(int x, int y, int width, int height) {
@@ -43,4 +52,98 @@ public Rectangle getRect() {
 		return new Rectangle(x, y, width, height);
 	}
 
+	/**
+	 * Sets a {@link ThemeResolver}.
+	 *
+	 * @param themeResolver the theme resolver
+	 */
+	public void setThemeResolver(@Nullable ThemeResolver themeResolver) {
+		this.themeResolver = themeResolver;
+	}
+
+	/**
+	 * Gets a {@link ThemeResolver}.
+	 *
+	 * @return a theme resolver
+	 */
+	@Nullable
+	protected ThemeResolver getThemeResolver() {
+		return themeResolver;
+	}
+
+	/**
+	 * Sets a theme name to use.
+	 *
+	 * @param themeName the theme name
+	 */
+	public void setThemeName(@Nullable String themeName) {
+		this.themeName = themeName;
+	}
+
+	/**
+	 * Gets a theme name.
+	 *
+	 * @return a theme name
+	 */
+	@Nullable
+	protected String getThemeName() {
+		return themeName;
+	}
+
+	private Optional<ResolvedValues> getThemeResolvedValues(String tag) {
+		ThemeResolver themeResolver = getThemeResolver();
+		if (themeResolver != null) {
+			String styleTag = themeResolver.resolveStyleTag(tag, getThemeName());
+			AttributedStyle attributedStyle = themeResolver.resolveStyle(styleTag);
+			return Optional.of(themeResolver.resolveValues(attributedStyle));
+		}
+		return Optional.empty();
+	}
+
+	/**
+	 * Resolve style using existing {@link ThemeResolver} and {@code theme name}.
+	 * Use {@code defaultStyle} if resolving cannot happen.
+	 *
+	 * @param tag the style tag to use
+	 * @param defaultStyle the default style to use
+	 * @return resolved style
+	 */
+	protected int resolveThemeStyle(String tag, int defaultStyle) {
+		return getThemeResolvedValues(tag).map(ResolvedValues::style).orElse(defaultStyle);
+	}
+
+	/**
+	 * Resolve foreground color using existing {@link ThemeResolver} and {@code theme name}.
+	 * {@code defaultColor} is used if it's value is not negative. {@code fallbackColor} is
+	 * used if theme resolver cannot be used.
+	 *
+	 * @param tag the style tag to use
+	 * @param defaultColor the default foreground color to use
+	 * @param fallbackColor the fallback foreground color to use
+	 * @return resolved foreground color
+	 */
+	protected int resolveThemeForeground(String tag, int defaultColor, int fallbackColor) {
+		if (defaultColor > -1) {
+			return defaultColor;
+		}
+		return getThemeResolvedValues(tag).map(ResolvedValues::foreground).orElse(fallbackColor);
+	}
+
+	/**
+	 * Resolve background color using existing {@link ThemeResolver} and {@code theme name}.
+	 * {@code defaultColor} is used if it's value is not negative. {@code fallbackColor} is
+	 * used if theme resolver cannot be used.
+	 *
+	 * @param tag the style tag to use
+	 * @param defaultColor the default background color to use
+	 * @param fallbackColor the fallback background color to use
+	 * @return resolved background color
+	 */
+	protected int resolveThemeBackground(String tag, int defaultColor, int fallbackColor) {
+		if (defaultColor > -1) {
+			return defaultColor;
+		}
+		return getThemeResolvedValues(tag).map(ResolvedValues::background).orElse(fallbackColor);
+	}
+
 }