feat: adding number input type

Author: Nicola Di Falco

spring-shell-core/src/main/java/org/springframework/shell/component/NumberInput.java

@@ -0,0 +1,265 @@
+/*
+ * Copyright 2022 the original author or authors.
+ *
+ * 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
+ *
+ *      https://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 org.springframework.shell.component;
+
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+import java.util.Optional;
+import java.util.function.Function;
+
+import org.jline.keymap.BindingReader;
+import org.jline.keymap.KeyMap;
+import org.jline.terminal.Terminal;
+import org.jline.utils.AttributedString;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.shell.component.NumberInput.NumberInputContext;
+import org.springframework.shell.component.context.ComponentContext;
+import org.springframework.shell.component.support.AbstractTextComponent;
+import org.springframework.shell.component.support.AbstractTextComponent.TextComponentContext.MessageLevel;
+import org.springframework.util.NumberUtils;
+import org.springframework.util.StringUtils;
+
+/**
+ * Component for a number input.
+ *
+ * @author Nicola Di Falco
+ */
+public class NumberInput extends AbstractTextComponent<Number, NumberInputContext> {
+
+	private static final Logger log = LoggerFactory.getLogger(NumberInput.class);
+	private final Number defaultValue;
+	private Class<? extends Number> clazz;
+	private NumberInputContext currentContext;
+
+	public NumberInput(Terminal terminal) {
+		this(terminal, null);
+	}
+
+	public NumberInput(Terminal terminal, String name) {
+		this(terminal, name, null);
+	}
+
+	public NumberInput(Terminal terminal, String name, Number defaultValue) {
+		this(terminal, name, defaultValue, Integer.class, null);
+	}
+
+	public NumberInput(Terminal terminal, String name, Number defaultValue, Class<? extends Number> clazz) {
+		this(terminal, name, defaultValue, clazz, null);
+	}
+
+	public NumberInput(Terminal terminal, String name, Number defaultValue, Class<? extends Number> clazz,
+			Function<NumberInputContext, List<AttributedString>> renderer) {
+		super(terminal, name, null);
+		setRenderer(renderer != null ? renderer : new DefaultRenderer());
+		setTemplateLocation("classpath:org/springframework/shell/component/number-input-default.stg");
+		this.defaultValue = defaultValue;
+		this.clazz = clazz;
+	}
+
+	public void setNumberClass(Class<? extends Number>  clazz) {
+		this.clazz = clazz;
+	}
+
+	@Override
+	public NumberInputContext getThisContext(ComponentContext<?> context) {
+		if (context != null && currentContext == context) {
+			return currentContext;
+		}
+		currentContext = NumberInputContext.of(defaultValue, clazz);
+		currentContext.setName(getName());
+		Optional.ofNullable(context).map(ComponentContext::stream)
+				.ifPresent(entryStream -> entryStream.forEach(e -> currentContext.put(e.getKey(), e.getValue())));
+		return currentContext;
+	}
+
+	@Override
+	protected boolean read(BindingReader bindingReader, KeyMap<String> keyMap, NumberInputContext context) {
+		String operation = bindingReader.readBinding(keyMap);
+		log.debug("Binding read result {}", operation);
+		if (operation == null) {
+			return true;
+		}
+		String input;
+		switch (operation) {
+			case OPERATION_CHAR:
+				String lastBinding = bindingReader.getLastBinding();
+				input = context.getInput();
+				if (input == null) {
+					input = lastBinding;
+				} else {
+					input = input + lastBinding;
+				}
+				context.setInput(input);
+				checkInput(input, context);
+				break;
+			case OPERATION_BACKSPACE:
+				input = context.getInput();
+				if (StringUtils.hasLength(input)) {
+					input = input.length() > 1 ? input.substring(0, input.length() - 1) : null;
+				}
+				context.setInput(input);
+				checkInput(input, context);
+				break;
+			case OPERATION_EXIT:
+				if (StringUtils.hasText(context.getInput())) {
+					context.setResultValue(parseNumber(context.getInput()));
+				}
+				else if (context.getDefaultValue() != null) {
+					context.setResultValue(context.getDefaultValue());
+				}
+				return true;
+			default:
+				break;
+		}
+		return false;
+	}
+
+	private Number parseNumber(String input) {
+		if (!StringUtils.hasText(input)) {
+			return null;
+		}
+
+		try {
+			return NumberUtils.parseNumber(input, clazz);
+		} catch (NumberFormatException e) {
+			return null;
+		}
+	}
+
+	private void checkInput(String input, NumberInputContext context) {
+		if (!StringUtils.hasText(input)) {
+			context.setMessage(null);
+			return;
+		}
+		Number num =  parseNumber(input);
+		if (num == null) {
+			String msg = String.format("Sorry, your input is invalid: '%s', try again", input);
+			context.setMessage(msg, MessageLevel.ERROR);
+		}
+		else {
+			context.setMessage(null);
+		}
+	}
+
+	public interface NumberInputContext extends TextComponentContext<Number, NumberInputContext> {
+
+		/**
+		 * Gets a default value.
+		 *
+		 * @return a default value
+		 */
+		Number getDefaultValue();
+
+		/**
+		 * Sets a default value.
+		 *
+		 * @param defaultValue the default value
+		 */
+		void setDefaultValue(Number defaultValue);
+
+		/**
+		 * Gets a default number class.
+		 *
+		 * @return a default number class
+		 */
+		Class<? extends Number> getDefaultClass();
+
+		/**
+		 * Sets a default number class.
+		 *
+		 * @param defaultClass the default number class
+		 */
+		void setDefaultClass(Class<? extends Number> defaultClass);
+
+		/**
+		 * Gets an empty {@link NumberInputContext}.
+		 *
+		 * @return empty number input context
+		 */
+		public static NumberInputContext empty() {
+			return of(null);
+		}
+
+		/**
+		 * Gets an {@link NumberInputContext}.
+		 *
+		 * @return number input context
+		 */
+		public static NumberInputContext of(Number defaultValue) {
+			return new DefaultNumberInputContext(defaultValue, Integer.class);
+		}
+
+		/**
+		 * Gets an {@link NumberInputContext}.
+		 *
+		 * @return number input context
+		 */
+		public static NumberInputContext of(Number defaultValue, Class<? extends Number> defaultClass) {
+			return new DefaultNumberInputContext(defaultValue, defaultClass);
+		}
+	}
+
+	private static class DefaultNumberInputContext extends BaseTextComponentContext<Number, NumberInputContext> implements NumberInputContext {
+
+		private Number defaultValue;
+		private Class<? extends Number> defaultClass;
+
+		public DefaultNumberInputContext(Number defaultValue, Class<? extends Number> defaultClass) {
+			this.defaultValue = defaultValue;
+			this.defaultClass = defaultClass;
+		}
+
+		@Override
+		public Number getDefaultValue() {
+			return defaultValue;
+		}
+
+		@Override
+		public void setDefaultValue(Number defaultValue) {
+			this.defaultValue = defaultValue;
+		}
+
+		@Override
+		public Class<? extends Number> getDefaultClass() {
+			return defaultClass;
+		}
+
+		@Override
+		public void setDefaultClass(Class<? extends Number> defaultClass) {
+			this.defaultClass = defaultClass;
+		}
+
+		@Override
+		public Map<String, Object> toTemplateModel() {
+			Map<String, Object> attributes = super.toTemplateModel();
+			attributes.put("defaultValue", getDefaultValue() != null ? getDefaultValue() : null);
+			attributes.put("defaultClass", getDefaultClass().getSimpleName());
+			Map<String, Object> model = new HashMap<>();
+			model.put("model", attributes);
+			return model;
+		}
+	}
+
+	private class DefaultRenderer implements Function<NumberInputContext, List<AttributedString>> {
+
+		@Override
+		public List<AttributedString> apply(NumberInputContext context) {
+			return renderTemplateResource(context.toTemplateModel());
+		}
+	}
+}