/*******************************************************************************
 * Copyright (c) 2012, 2016 NumberFour AG and others
 *
 * This program and the accompanying materials are made available under the
 * terms of the Eclipse Public License v. 2.0 which is available at
 * http://www.eclipse.org/legal/epl-2.0.
 * 
 * SPDX-License-Identifier: EPL-2.0
 *
 * Contributors:
 *     NumberFour AG - initial API and Implementation (Alex Panchenko)
 *******************************************************************************/
package org.eclipse.dltk.javascript.ui.tests.codeassist;

import static com.google.common.base.Preconditions.checkNotNull;

import java.util.List;

import org.eclipse.core.runtime.CoreException;
import org.eclipse.dltk.core.ISourceModule;
import org.eclipse.dltk.core.tests.ProjectSetup;
import org.eclipse.dltk.javascript.ast.Keywords;
import org.eclipse.dltk.javascript.ast.MultiLineComment;
import org.eclipse.dltk.javascript.typeinfo.ITypeNames;
import org.eclipse.dltk.javascript.ui.tests.AllTests;
import org.eclipse.dltk.ui.templates.ScriptTemplateProposal;
import org.eclipse.dltk.ui.tests.UICompletionUtil;
import org.eclipse.dltk.ui.tests.UITestUtils;
import org.eclipse.dltk.ui.text.completion.IScriptCompletionProposal;
import org.eclipse.jface.text.contentassist.ICompletionProposal;
import org.hamcrest.CoreMatchers;
import org.hamcrest.Matcher;
import org.junit.After;
import org.junit.Assert;
import org.junit.ClassRule;
import org.junit.Test;

import com.google.common.base.Predicate;
import com.google.common.base.Predicates;
import com.google.common.collect.FluentIterable;
import com.google.common.collect.Lists;

public class JSCodeAssistUITest extends Assert {

	@ClassRule
	public static final ProjectSetup PROJECT = new ProjectSetup(
			AllTests.WORKSPACE, "completion");

	@After
	public void closeAllEditors() {
		UITestUtils.closeAllEditors();
	}

	private static <T extends ICompletionProposal> List<T> filter(
			List<ICompletionProposal> proposals, Class<T> proposalClass,
			Predicate<T> predicate) {
		return FluentIterable.from(proposals).filter(proposalClass)
				.filter(predicate).toList();
	}

	private List<ScriptTemplateProposal> filterProposalsWithJSDoc(
			final List<ICompletionProposal> proposals) {
		return filter(proposals, ScriptTemplateProposal.class,
				input -> input.getAdditionalProposalInfo()
						.contains(MultiLineComment.JSDOC_PREFIX));
	}

	private static Matcher<String> stringHasValue() {
		return CoreMatchers.allOf(CoreMatchers.<String> notNullValue(String.class),
				CoreMatchers.not(""));
	}

	@Test
	public void functionDeclaration() throws CoreException {
		final ISourceModule module = checkNotNull(PROJECT.getSourceModule(
				"src", "function-declaration.js"));

		final UICompletionUtil util = UICompletionUtil.openEditor(module)
				.after("fu");

		final List<ICompletionProposal> proposals = util.invokeCompletion();
		assertEquals(4, proposals.size());

		// function keyword
		final List<IScriptCompletionProposal> keywords = filter(proposals,
				IScriptCompletionProposal.class,
				input -> Keywords.FUNCTION.equals(input.getDisplayString()));
		assertEquals(1, keywords.size());

		// 2 function declaration templates (with jsdoc and without it)
		final List<ScriptTemplateProposal> templates = filter(proposals,
				ScriptTemplateProposal.class,
				Predicates.<ScriptTemplateProposal> alwaysTrue());
		assertEquals(2, templates.size());

		// Function global
		final List<ICompletionProposal> globals = Lists.newArrayList(proposals);
		globals.removeAll(keywords);
		globals.removeAll(templates);
		assertEquals(1, globals.size());
		assertEquals(ITypeNames.FUNCTION, globals.get(0).getDisplayString());
	}

	@Test
	public void functionKeywordProposal() throws CoreException {
		final ISourceModule module = checkNotNull(PROJECT.getSourceModule(
				"src", "file1.js"));

		final UICompletionUtil util = UICompletionUtil.openEditor(module)
				.after("fu");

		final List<ICompletionProposal> proposals = util.invokeCompletion();
		assertFalse(proposals.isEmpty());

		final List<IScriptCompletionProposal> keywords = filter(proposals,
				IScriptCompletionProposal.class,
				input -> Keywords.FUNCTION.equals(input.getDisplayString()));
		assertEquals(1, keywords.size());
		util.apply(keywords.get(0));
		assertEquals(PROJECT.getFileContentsAsString("src/file1keyword.txt"),
				util.getText());
	}

	@Test
	public void functionWithJSDoc() throws CoreException {
		final ISourceModule module = checkNotNull(PROJECT.getSourceModule(
				"src", "file1.js"));
		final UICompletionUtil util = UICompletionUtil.openEditor(module)
				.after("fu");

		final List<ScriptTemplateProposal> templates = filterProposalsWithJSDoc(util
				.invokeCompletion());
		assertEquals(1, templates.size());

		util.apply(templates.get(0));
		assertEquals(PROJECT.getFileContentsAsString("src/file1.txt"),
				util.getText());
	}

	@Test
	public void secondFunctionWithJSDoc() throws CoreException {
		final ISourceModule module = checkNotNull(PROJECT.getSourceModule(
				"src", "file2.js"));
		final UICompletionUtil util = UICompletionUtil.openEditor(module)
				.afterLast("fu");

		final List<ScriptTemplateProposal> templates = filterProposalsWithJSDoc(util
				.invokeCompletion());
		assertEquals(1, templates.size());

		util.apply(templates.get(0));
		assertEquals(PROJECT.getFileContentsAsString("src/file2.txt"),
				util.getText());
	}

	@Test
	public void functionWithJSDocIfJSDocAlreadyExists() throws CoreException {
		final ISourceModule module = checkNotNull(PROJECT.getSourceModule(
				"src", "file3.js"));
		final UICompletionUtil util = UICompletionUtil.openEditor(module)
				.afterLast("fu");

		final List<ScriptTemplateProposal> templates = filterProposalsWithJSDoc(util
				.invokeCompletion());
		assertEquals(1, templates.size());

		util.apply(templates.get(0));
		assertEquals(PROJECT.getFileContentsAsString("src/file3.txt"),
				util.getText());
	}

	@Test
	public void additionalProposalInfoLengthProperty() throws CoreException {
		final ISourceModule module = checkNotNull(PROJECT.getSourceModule(
				"src", "additionalInfo.js"));
		final UICompletionUtil util = UICompletionUtil.openEditor(module)
				.afterLast("s.");

		final List<IScriptCompletionProposal> proposals = filter(
				util.invokeCompletion(), IScriptCompletionProposal.class,
				input -> input.getDisplayString().startsWith("length"));
		assertEquals(1, proposals.size());
		assertThat(proposals.get(0).getAdditionalProposalInfo(),
				stringHasValue());
	}

	@Test
	public void additionalProposalInfoToStringMethod() throws CoreException {
		final ISourceModule module = checkNotNull(PROJECT.getSourceModule(
				"src", "additionalInfo.js"));
		final UICompletionUtil util = UICompletionUtil.openEditor(module)
				.afterLast("s.");

		final List<IScriptCompletionProposal> proposals = filter(
				util.invokeCompletion(), IScriptCompletionProposal.class,
				input -> input.getDisplayString().startsWith("toString"));
		assertEquals(1, proposals.size());
		assertThat(proposals.get(0).getAdditionalProposalInfo(),
				stringHasValue());
	}

}