/*
 * Copyright 2018 OpenAPI-Generator Contributors (https://openapi-generator.tech)
 * Copyright 2018 SmartBear Software
 *
 * 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.openapitools.codegen.languages;

import com.samskivert.mustache.Mustache;
import com.samskivert.mustache.Template;
import io.swagger.v3.oas.models.media.ArraySchema;
import io.swagger.v3.oas.models.media.Schema;
import org.apache.commons.lang3.StringUtils;
import org.openapitools.codegen.*;
import org.openapitools.codegen.meta.features.*;
import org.openapitools.codegen.utils.ModelUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.io.File;
import java.io.IOException;
import java.io.StringWriter;
import java.io.Writer;
import java.util.Arrays;
import java.util.EnumSet;
import java.util.HashMap;

import static org.openapitools.codegen.utils.CamelizeOption.LOWERCASE_FIRST_LETTER;
import static org.openapitools.codegen.utils.StringUtils.camelize;
import static org.openapitools.codegen.utils.StringUtils.underscore;

public class ScalazClientCodegen extends AbstractScalaCodegen implements CodegenConfig {
    private final Logger LOGGER = LoggerFactory.getLogger(ScalazClientCodegen.class);

    public ScalazClientCodegen() {
        super();

        modifyFeatureSet(features -> features
                .wireFormatFeatures(EnumSet.of(WireFormatFeature.JSON))
                .securityFeatures(EnumSet.noneOf(SecurityFeature.class))
                .excludeGlobalFeatures(
                        GlobalFeature.XMLStructureDefinitions,
                        GlobalFeature.Callbacks,
                        GlobalFeature.LinkObjects,
                        GlobalFeature.ParameterStyling
                )
                .excludeSchemaSupportFeatures(
                        SchemaSupportFeature.Polymorphism
                )
                .excludeParameterFeatures(
                        ParameterFeature.Cookie
                )
        );

        outputFolder = "generated-code/scalaz";
        embeddedTemplateDir = templateDir = "scalaz";
        apiPackage = "org.openapitools.client.api";
        modelPackage = "org.openapitools.client.api";

        modelTemplateFiles.put("model.mustache", ".scala");
        apiTemplateFiles.put("api.mustache", ".scala");

        setReservedWordsLowerCase(
                Arrays.asList(
                        // local variable names used in API methods (endpoints)
                        "path", "contentTypes", "contentType", "queryParams", "headerParams",
                        "formParams", "postBody", "mp", "basePath", "apiInvoker",

                        // scala reserved words
                        "abstract", "case", "catch", "class", "def", "do", "else", "extends",
                        "false", "final", "finally", "for", "forSome", "if", "implicit",
                        "import", "lazy", "match", "new", "null", "object", "override", "package",
                        "private", "protected", "return", "sealed", "super", "this", "throw",
                        "trait", "try", "true", "type", "val", "var", "while", "with", "yield")
        );

        additionalProperties.put("apiPackage", apiPackage);

        // Explicitly defining build.properties helps guarantee our sample remains compilable against the embedded target 2.11 scala
        supportingFiles.add(new SupportingFile("build.properties.mustache", "", "project/build.properties"));
        supportingFiles.add(new SupportingFile("build.sbt.mustache", "", "build.sbt"));
        supportingFiles.add(new SupportingFile("dateTimeCodecs.mustache", (sourceFolder + File.separator + apiPackage).replace(".", File.separator), "DateTimeCodecs.scala"));
        supportingFiles.add(new SupportingFile("HelperCodecs.mustache", (sourceFolder + File.separator + apiPackage).replace(".", File.separator), "HelperCodecs.scala"));
        supportingFiles.add(new SupportingFile("QueryParamTypeclass.mustache", (sourceFolder + File.separator + apiPackage).replace(".", File.separator), "QueryParamTypeclass.scala"));

        importMapping.remove("List");
        importMapping.remove("Set");
        importMapping.remove("Map");

        // Overrides defaults applied in DefaultCodegen which don't apply cleanly to Scala.
        importMapping.put("Date", "java.util.Date");
        importMapping.put("DateTime", "org.joda.time.DateTime");
        importMapping.put("LocalDateTime", "org.joda.time.LocalDateTime");
        importMapping.put("LocalDate", "org.joda.time.LocalDate");
        importMapping.put("LocalTime", "org.joda.time.LocalTime");

        typeMapping = new HashMap<String, String>();
        typeMapping.put("enum", "NSString");
        typeMapping.put("array", "List");
        typeMapping.put("set", "Set");
        typeMapping.put("boolean", "Boolean");
        typeMapping.put("string", "String");
        typeMapping.put("int", "Int");
        typeMapping.put("long", "Long");
        typeMapping.put("float", "Float");
        typeMapping.put("byte", "Byte");
        typeMapping.put("short", "Short");
        typeMapping.put("char", "Char");
        typeMapping.put("double", "Double");
        typeMapping.put("object", "Any");
        typeMapping.put("file", "File");
        typeMapping.put("binary", "File");
        typeMapping.put("number", "BigDecimal");
        typeMapping.put("decimal", "BigDecimal");
        typeMapping.put("date-time", "DateTime");
        typeMapping.put("date", "DateTime");

        instantiationTypes.put("array", "ListBuffer");
        instantiationTypes.put("map", "HashMap");

        additionalProperties.put("fnEnumEntry", new EnumEntryLambda());
    }

    @Override
    public void processOpts() {
        super.processOpts();
    }

    @Override
    public String toParamName(String name) {
        // should be the same as variable name
        return toVarName(name);
    }

    @Override
    public String toEnumName(CodegenProperty property) {
        return formatIdentifier(property.baseName, true);
    }

    public String getNameUsingModelPropertyNaming(String name) {
        switch (CodegenConstants.MODEL_PROPERTY_NAMING_TYPE.valueOf(getModelPropertyNaming())) {
            case original:
                return name;
            case camelCase:
                return camelize(name, LOWERCASE_FIRST_LETTER);
            case PascalCase:
                return camelize(name);
            case snake_case:
                return underscore(name);
            default:
                throw new IllegalArgumentException("Invalid model property naming '" +
                        name + "'. Must be 'original', 'camelCase', " +
                        "'PascalCase' or 'snake_case'");
        }

    }

    @Override
    public String toDefaultValue(Schema p) {
        if (p.getDefault() != null) {
            return p.getDefault().toString();
        }

        // comment out the following as the default value is no handled differently
        if (ModelUtils.isBooleanSchema(p)) {
            return null;
        } else if (ModelUtils.isDateSchema(p)) {
            return null;
        } else if (ModelUtils.isDateTimeSchema(p)) {
            return null;
        } else if (ModelUtils.isNumberSchema(p)) {
            return null;
        } else if (ModelUtils.isIntegerSchema(p)) {
            return null;
        } else if (ModelUtils.isMapSchema(p)) {
            String inner = getSchemaType(ModelUtils.getAdditionalProperties(p));

            return "Map.empty[String, " + inner + "] ";
        } else if (ModelUtils.isArraySchema(p)) {
            ArraySchema ap = (ArraySchema) p;
            String inner = getSchemaType(ap.getItems());
            String collectionType = ModelUtils.isSet(ap) ? typeMapping.get("set") : typeMapping.get("array");

            // We assume that users would map these collections to a monoid with an identity function
            // There's no reason to assume mutable structure here (which may make consumption more difficult)
            return collectionType + ".empty[" + inner + "] ";
        } else if (ModelUtils.isStringSchema(p)) {
            return null;
        } else {
            return null;
        }
    }

    @Override
    public CodegenType getTag() {
        return CodegenType.CLIENT;
    }

    @Override
    public String getName() {
        return "scalaz";
    }

    @Override
    public String getHelp() {
        return "Generates a Scalaz client library (beta) that uses http4s";
    }

    @Override
    public String toOperationId(String operationId) {
        // throw exception if method name is empty
        if (StringUtils.isEmpty(operationId)) {
            throw new RuntimeException("Empty method name (operationId) not allowed");
        }

        // method name cannot use reserved keyword, e.g. return
        if (isReservedWord(operationId)) {
            throw new RuntimeException(operationId + " (reserved word) cannot be used as method name");
        }

        return camelize(operationId, LOWERCASE_FIRST_LETTER);
    }

    private static abstract class CustomLambda implements Mustache.Lambda {
        @Override
        public void execute(Template.Fragment frag, Writer out) throws IOException {
            final StringWriter tempWriter = new StringWriter();
            frag.execute(tempWriter);
            out.write(formatFragment(tempWriter.toString()));
        }

        public abstract String formatFragment(String fragment);
    }

    private class EnumEntryLambda extends CustomLambda {
        @Override
        public String formatFragment(String fragment) {
            return formatIdentifier(fragment, true);
        }
    }
}
