org.ballerinalang.langserver.completions.providers.contextproviders.MatchStatementContextProvider.java Source code

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Here is the source code for org.ballerinalang.langserver.completions.providers.contextproviders.MatchStatementContextProvider.java

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/*
 *  Copyright (c) 2018, WSO2 Inc. (http://www.wso2.org) All Rights Reserved.
 *
 *  WSO2 Inc. licenses this file to you 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 org.ballerinalang.langserver.completions.providers.contextproviders;

import org.antlr.v4.runtime.CommonToken;
import org.antlr.v4.runtime.Token;
import org.ballerinalang.annotation.JavaSPIService;
import org.ballerinalang.langserver.common.UtilSymbolKeys;
import org.ballerinalang.langserver.common.utils.CommonUtil;
import org.ballerinalang.langserver.common.utils.FilterUtils;
import org.ballerinalang.langserver.compiler.LSContext;
import org.ballerinalang.langserver.completions.CompletionKeys;
import org.ballerinalang.langserver.completions.SymbolInfo;
import org.ballerinalang.langserver.completions.builder.BFunctionCompletionItemBuilder;
import org.ballerinalang.langserver.completions.builder.BTypeCompletionItemBuilder;
import org.ballerinalang.langserver.completions.builder.BVariableCompletionItemBuilder;
import org.ballerinalang.langserver.completions.spi.LSCompletionProvider;
import org.ballerinalang.langserver.completions.util.sorters.ItemSorters;
import org.ballerinalang.langserver.completions.util.sorters.MatchContextItemSorter;
import org.eclipse.lsp4j.CompletionItem;
import org.eclipse.lsp4j.InsertTextFormat;
import org.wso2.ballerinalang.compiler.parser.antlr4.BallerinaParser;
import org.wso2.ballerinalang.compiler.semantics.model.symbols.BInvokableSymbol;
import org.wso2.ballerinalang.compiler.semantics.model.symbols.BPackageSymbol;
import org.wso2.ballerinalang.compiler.semantics.model.symbols.BSymbol;
import org.wso2.ballerinalang.compiler.semantics.model.symbols.BVarSymbol;
import org.wso2.ballerinalang.compiler.semantics.model.types.BRecordType;
import org.wso2.ballerinalang.compiler.semantics.model.types.BTupleType;
import org.wso2.ballerinalang.compiler.semantics.model.types.BType;
import org.wso2.ballerinalang.util.Flags;

import java.util.ArrayList;
import java.util.List;
import java.util.stream.Collectors;

import static org.ballerinalang.langserver.common.utils.CommonUtil.LINE_SEPARATOR;
import static org.ballerinalang.langserver.completions.util.MatchStatementResolverUtil.generateMatchPattern;
import static org.ballerinalang.langserver.completions.util.MatchStatementResolverUtil.getStructuredFixedValueMatch;
import static org.ballerinalang.langserver.completions.util.MatchStatementResolverUtil.getVariableValueDestructurePattern;

/**
 * Completion Item provider for the match statement parser rule context.
 */
@JavaSPIService("org.ballerinalang.langserver.completions.spi.LSCompletionProvider")
public class MatchStatementContextProvider extends LSCompletionProvider {

    public MatchStatementContextProvider() {
        this.attachmentPoints.add(BallerinaParser.MatchStatementContext.class);
    }

    @Override
    public List<CompletionItem> getCompletions(LSContext ctx) {
        ArrayList<CompletionItem> completionItems = new ArrayList<>();
        List<CommonToken> lhsTokens = ctx.get(CompletionKeys.LHS_TOKENS_KEY).stream()
                .filter(commonToken -> commonToken.getChannel() == Token.DEFAULT_CHANNEL)
                .collect(Collectors.toList());
        List<SymbolInfo> symbolInfoList = ctx.get(CompletionKeys.VISIBLE_SYMBOLS_KEY);
        if (isInvocationOrInteractionOrFieldAccess(ctx)) {
            String delimiter = "";
            String variableName = "";
            for (int i = 0; i < lhsTokens.size(); i++) {
                if (lhsTokens.get(i).getType() == BallerinaParser.DOT
                        || lhsTokens.get(i).getType() == BallerinaParser.COLON
                        || lhsTokens.get(i).getType() == BallerinaParser.RARROW) {
                    delimiter = lhsTokens.get(i).getText();
                    variableName = lhsTokens.get(i - 1).getText();
                    break;
                }
            }
            List<SymbolInfo> filteredList = FilterUtils.getInvocationAndFieldSymbolsOnVar(ctx, variableName,
                    delimiter, ctx.get(CompletionKeys.VISIBLE_SYMBOLS_KEY), false);
            filteredList.removeIf(CommonUtil.invalidSymbolsPredicate());
            filteredList.forEach(symbolInfo -> {
                if (CommonUtil.isValidInvokableSymbol(symbolInfo.getScopeEntry().symbol)) {
                    BSymbol scopeEntrySymbol = symbolInfo.getScopeEntry().symbol;
                    completionItems.add(this.fillInvokableSymbolMatchSnippet((BInvokableSymbol) scopeEntrySymbol));
                }
            });
        } else {
            symbolInfoList.removeIf(CommonUtil.invalidSymbolsPredicate());
            symbolInfoList.forEach(symbolInfo -> {
                BSymbol bSymbol = symbolInfo.getScopeEntry().symbol;
                if (CommonUtil.isValidInvokableSymbol(symbolInfo.getScopeEntry().symbol)
                        && ((bSymbol.flags & Flags.ATTACHED) != Flags.ATTACHED)) {
                    completionItems.add(this.fillInvokableSymbolMatchSnippet((BInvokableSymbol) bSymbol));
                } else if (!(symbolInfo.getScopeEntry().symbol instanceof BInvokableSymbol)
                        && bSymbol instanceof BVarSymbol) {
                    fillVarSymbolMatchSnippet((BVarSymbol) bSymbol, completionItems);
                    String typeName = symbolInfo.getScopeEntry().symbol.type.toString();
                    completionItems.add(BVariableCompletionItemBuilder.build((BVarSymbol) bSymbol,
                            symbolInfo.getSymbolName(), typeName));
                } else if (bSymbol instanceof BPackageSymbol) {
                    completionItems.add(
                            BTypeCompletionItemBuilder.build((BPackageSymbol) bSymbol, symbolInfo.getSymbolName()));
                }
            });
        }
        ItemSorters.get(MatchContextItemSorter.class).sortItems(ctx, completionItems);

        return completionItems;
    }

    private CompletionItem getVariableCompletionItem(BVarSymbol varSymbol, String matchFieldSnippet, String label) {
        CompletionItem completionItem = BVariableCompletionItemBuilder.build(varSymbol, label,
                varSymbol.type.toString());
        completionItem.setInsertText(varSymbol.getName().getValue() + " " + matchFieldSnippet);
        completionItem.setInsertTextFormat(InsertTextFormat.Snippet);
        return completionItem;
    }

    private String getFunctionSignature(BInvokableSymbol func) {
        String[] nameComps = func.getName().getValue().split("\\.");
        StringBuilder signature = new StringBuilder(nameComps[nameComps.length - 1]);
        List<String> params = new ArrayList<>();
        signature.append(UtilSymbolKeys.OPEN_PARENTHESES_KEY);
        func.getParameters().forEach(bVarSymbol -> params.add(bVarSymbol.getName().getValue()));
        func.getDefaultableParameters().forEach(bVarSymbol -> params.add(bVarSymbol.getName().getValue()));
        signature.append(String.join(",", params)).append(")");

        return signature.toString();
    }

    private CompletionItem fillInvokableSymbolMatchSnippet(BInvokableSymbol func) {
        String functionSignature = getFunctionSignature(func);
        String variableValuePattern = getVariableValueDestructurePattern();
        String variableValueSnippet = this.generateMatchSnippet(variableValuePattern);

        return BFunctionCompletionItemBuilder.build(func, functionSignature,
                functionSignature + " " + variableValueSnippet);
    }

    private void fillVarSymbolMatchSnippet(BVarSymbol varSymbol, List<CompletionItem> completionItems) {
        BType symbolType = varSymbol.getType();
        String varName = varSymbol.getName().getValue();
        if (symbolType instanceof BTupleType || symbolType instanceof BRecordType) {
            String fixedValuePattern = "\t" + generateMatchPattern(getStructuredFixedValueMatch(symbolType));
            String fixedValueSnippet = this.generateMatchSnippet(fixedValuePattern);
            completionItems.add(this.getVariableCompletionItem(varSymbol, fixedValueSnippet, varName));
        } else {
            String variableValuePattern = "\t" + getVariableValueDestructurePattern();
            String variableValueSnippet = this.generateMatchSnippet(variableValuePattern);
            completionItems.add(this.getVariableCompletionItem(varSymbol, variableValueSnippet, varName));
        }
    }

    private String generateMatchSnippet(String patternClause) {
        return UtilSymbolKeys.OPEN_BRACE_KEY + LINE_SEPARATOR + patternClause + LINE_SEPARATOR
                + UtilSymbolKeys.CLOSE_BRACE_KEY;
    }
}