dev.steinerok.sealant.viewmodel.generator.ViewModelCreationGenerator.kt Maven / Gradle / Ivy

Go to download
Show more of this group Show more artifacts with this name
Show all versions of sealant-viewmodel-codegen Show documentation
Android injection using the Anvil and Dagger2.
The newest version!
/*
 * Copyright 2022 Ihor Kushnirenko
 *
 * 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 dev.steinerok.sealant.viewmodel.generator

import com.google.auto.service.AutoService
import com.squareup.anvil.compiler.api.CodeGenerator
import com.squareup.anvil.compiler.api.FileWithContent
import com.squareup.anvil.compiler.api.GeneratedFileWithSources
import com.squareup.anvil.compiler.api.createGeneratedFile
import com.squareup.anvil.compiler.internal.reference.ClassReference
import com.squareup.anvil.compiler.internal.reference.asClassName
import com.squareup.anvil.compiler.internal.reference.classAndInnerClassReferences
import com.squareup.anvil.compiler.internal.reference.generateClassName
import com.squareup.anvil.compiler.internal.safePackageString
import com.squareup.kotlinpoet.ClassName
import com.squareup.kotlinpoet.FileSpec
import com.squareup.kotlinpoet.KModifier
import dev.steinerok.sealant.core.AnnotationSpec
import dev.steinerok.sealant.core.ClassNames
import dev.steinerok.sealant.core.FqNames
import dev.steinerok.sealant.core.FunSpec
import dev.steinerok.sealant.core.InterfaceSpec
import dev.steinerok.sealant.core.ObjectSpec
import dev.steinerok.sealant.core.ParameterSpec
import dev.steinerok.sealant.core.SealantFeature
import dev.steinerok.sealant.core.addContributesTo
import dev.steinerok.sealant.core.buildFile
import dev.steinerok.sealant.core.buildVmScopeClassName
import dev.steinerok.sealant.core.generator.AlwaysApplicableCodeGenerator
import dev.steinerok.sealant.core.getScopeFrom
import dev.steinerok.sealant.core.hasSealantFeatureForScope
import dev.steinerok.sealant.core.isViewModel
import dev.steinerok.sealant.viewmodel.contributesViewModel
import dev.steinerok.sealant.viewmodel.javaClazzOutViewModel
import dev.steinerok.sealant.viewmodel.sealantViewModelMap
import dev.steinerok.sealant.viewmodel.sealantViewModelMapKeySet
import dev.steinerok.sealant.viewmodel.viewModelKey
import org.jetbrains.kotlin.descriptors.ModuleDescriptor
import org.jetbrains.kotlin.psi.KtFile
import java.io.File

/**
 * Source generator to support Sealant injection of ViewModels.
 *
 * Should generate:
 * ```
 * @Module
 * @ContributesTo(scope = ::class)
 * public object _KeyModule {
 *   @Provides
 *   @IntoSet
 *   @SealantViewModelMap.KeySet
 *   public fun provideKey(): Class = ::class.java
 * }
 *
 * @Module
 * @ContributesTo(scope = ViewModel_::class)
 * public interface _BindsModule {
 *   @Binds
 *   @IntoMap
 *   @ViewModelKey(::class)
 *   @SealantViewModelMap
 *   public fun bind(instance: ): ViewModel
 * }
 * ```
 *
 * related with Hilt codegen:
 * ```
 * public final class $_HiltModules {
 *   @Module
 *   @InstallIn(ViewModelComponent.class)
 *   public static abstract class BindsModule {
 *     @Binds
 *     @IntoMap
 *     @StringKey("pkg.$")
 *     @HiltViewModelMap
 *     public abstract ViewModel bind($ vm)
 *   }
 *
 *   @Module
 *   @InstallIn(ActivityRetainedComponent.class)
 *   public static final class KeyModule {
 *     @Provides
 *     @IntoSet
 *     @HiltViewModelMap.KeySet
 *     public static String provide() {
 *      return "pkg.$";
 *     }
 *   }
 * }
 * ```
 */
@AutoService(CodeGenerator::class)
public class ViewModelCreationGenerator : AlwaysApplicableCodeGenerator {

    override fun generateCode(
        codeGenDir: File,
        module: ModuleDescriptor,
        projectFiles: Collection
    ): Collection = projectFiles
        .classAndInnerClassReferences(module)
        .filter { clazz ->
            clazz.isAnnotatedWith(FqNames.contributesViewModel) &&
                    clazz.getScopeFrom(FqNames.contributesViewModel)
                        .hasSealantFeatureForScope(SealantFeature.ViewModel)
        }
        .onEach { clazz ->
            require(clazz.isViewModel()) {
                "The annotation `@SealantViewModel` can only be applied " +
                        "to classes which extend ${FqNames.androidxViewModel.asString()}"
            }
        }
        .flatMap { clazz ->
            listOfNotNull(generateCreation(codeGenDir, clazz))
        }
        .toList()

    private fun generateCreation(
        codeGenDir: File,
        clazz: ClassReference,
    ): GeneratedFileWithSources {
        val packageName = clazz.packageFqName.safePackageString(dotSuffix = false)
        val fileName = clazz.generateClassName().relativeClassName.asString() + "_Creation"
        //
        val content = FileSpec.buildFile(packageName, fileName) {
            val origClassName = clazz.asClassName()
            val origShortName = clazz.shortName
            val scopeFqName = clazz.getScopeFrom(FqNames.contributesViewModel)
            val scopeClassName = scopeFqName.asClassName()
            val vmScopeClassName = buildVmScopeClassName(scopeClassName)
            //
            val kmNameStr = "${origShortName}_KeyModule"
            val kmClassName = ClassName(packageName, kmNameStr)
            val kmObject = ObjectSpec(kmClassName) {
                addAnnotation(ClassNames.module)
                addContributesTo(scopeClassName)
                addFunction(
                    FunSpec("provide${origShortName}Key") {
                        addAnnotation(ClassNames.provides)
                        addAnnotation(ClassNames.intoSet)
                        addAnnotation(ClassNames.sealantViewModelMapKeySet)
                        returns(ClassNames.javaClazzOutViewModel)
                        addStatement("return·%T::class.java", origClassName)
                    }
                )
            }
            addType(kmObject)
            //
            val bmNameStr = "${origShortName}_BindsModule"
            val bmClassName = ClassName(packageName, bmNameStr)
            val bmInterface = InterfaceSpec(bmClassName) {
                addAnnotation(ClassNames.module)
                addContributesTo(vmScopeClassName)
                addFunction(
                    FunSpec("bind") {
                        addAnnotation(ClassNames.binds)
                        addAnnotation(ClassNames.intoMap)
                        addAnnotation(
                            AnnotationSpec(ClassNames.viewModelKey) {
                                addMember("%T::class", origClassName)
                            }
                        )
                        addAnnotation(ClassNames.sealantViewModelMap)
                        addModifiers(KModifier.ABSTRACT)
                        addParameter(ParameterSpec("instance", origClassName))
                        returns(ClassNames.androidxViewModel)
                    }
                )
            }
            addType(bmInterface)
        }
        return createGeneratedFile(
            codeGenDir = codeGenDir,
            packageName = packageName,
            fileName = fileName,
            content = content,
            sourceFile = clazz.containingFileAsJavaFile,
        )
    }
}