package org.jetbrains.dokka

import com.intellij.core.CoreApplicationEnvironment
import com.intellij.core.CoreModuleManager
import com.intellij.mock.MockComponentManager
import com.intellij.openapi.Disposable
import com.intellij.openapi.extensions.Extensions
import com.intellij.openapi.module.Module
import com.intellij.openapi.module.ModuleManager
import com.intellij.openapi.project.Project
import com.intellij.openapi.roots.OrderEnumerationHandler
import com.intellij.openapi.roots.ProjectFileIndex
import com.intellij.openapi.roots.ProjectRootManager
import com.intellij.openapi.util.Disposer
import com.intellij.openapi.vfs.StandardFileSystems
import com.intellij.psi.PsiElement
import com.intellij.psi.search.GlobalSearchScope
import com.intellij.util.io.URLUtil
import org.jetbrains.kotlin.analyzer.*
import org.jetbrains.kotlin.cli.common.CLIConfigurationKeys
import org.jetbrains.kotlin.cli.common.messages.MessageCollector
import org.jetbrains.kotlin.cli.jvm.compiler.EnvironmentConfigFiles
import org.jetbrains.kotlin.cli.jvm.compiler.JvmPackagePartProvider
import org.jetbrains.kotlin.cli.jvm.compiler.KotlinCoreEnvironment
import org.jetbrains.kotlin.cli.jvm.compiler.TopDownAnalyzerFacadeForJVM
import org.jetbrains.kotlin.cli.jvm.config.*
import org.jetbrains.kotlin.cli.jvm.index.JavaRoot
import org.jetbrains.kotlin.config.*
import org.jetbrains.kotlin.container.getService
import org.jetbrains.kotlin.context.ProjectContext
import org.jetbrains.kotlin.descriptors.DeclarationDescriptor
import org.jetbrains.kotlin.descriptors.ModuleDescriptor
import org.jetbrains.kotlin.idea.resolve.ResolutionFacade
import org.jetbrains.kotlin.load.java.structure.impl.JavaClassImpl
import org.jetbrains.kotlin.name.Name
import org.jetbrains.kotlin.platform.JvmBuiltIns
import org.jetbrains.kotlin.psi.KtDeclaration
import org.jetbrains.kotlin.psi.KtElement
import org.jetbrains.kotlin.psi.KtFile
import org.jetbrains.kotlin.resolve.BindingContext
import org.jetbrains.kotlin.resolve.CompilerEnvironment
import org.jetbrains.kotlin.resolve.jvm.JvmAnalyzerFacade
import org.jetbrains.kotlin.resolve.jvm.JvmPlatformParameters
import org.jetbrains.kotlin.resolve.jvm.platform.JvmPlatform
import org.jetbrains.kotlin.resolve.lazy.BodyResolveMode
import org.jetbrains.kotlin.resolve.lazy.ResolveSession
import java.io.File

/**
 * Kotlin as a service entry point
 *
 * Configures environment, analyses files and provides facilities to perform code processing without emitting bytecode
 *
 * $messageCollector: required by compiler infrastructure and will receive all compiler messages
 * $body: optional and can be used to configure environment without creating local variable
 */
class AnalysisEnvironment(val messageCollector: MessageCollector) : Disposable {
    val configuration = CompilerConfiguration()

    init {
        configuration.put(CLIConfigurationKeys.MESSAGE_COLLECTOR_KEY, messageCollector)
    }

    fun createCoreEnvironment(): KotlinCoreEnvironment {
        System.setProperty("idea.io.use.fallback", "true")
        val environment = KotlinCoreEnvironment.createForProduction(this, configuration, EnvironmentConfigFiles.JVM_CONFIG_FILES)
        val projectComponentManager = environment.project as MockComponentManager

        val projectFileIndex = CoreProjectFileIndex(environment.project,
                environment.configuration.getList(JVMConfigurationKeys.CONTENT_ROOTS))

        val moduleManager = object : CoreModuleManager(environment.project, this) {
            override fun getModules(): Array<out Module> = arrayOf(projectFileIndex.module)
        }

        CoreApplicationEnvironment.registerComponentInstance(projectComponentManager.picoContainer,
                ModuleManager::class.java, moduleManager)

        Extensions.registerAreaClass("IDEA_MODULE", null)
        CoreApplicationEnvironment.registerExtensionPoint(Extensions.getRootArea(),
                OrderEnumerationHandler.EP_NAME, OrderEnumerationHandler.Factory::class.java)

        projectComponentManager.registerService(ProjectFileIndex::class.java,
                projectFileIndex)
        projectComponentManager.registerService(ProjectRootManager::class.java,
                CoreProjectRootManager(projectFileIndex))
        return environment
    }

    fun createSourceModuleSearchScope(project: Project, sourceFiles: List<KtFile>): GlobalSearchScope {
        // TODO: Fix when going to implement dokka for JS
        return TopDownAnalyzerFacadeForJVM.newModuleSearchScope(project, sourceFiles)
    }


    fun createResolutionFacade(environment: KotlinCoreEnvironment): DokkaResolutionFacade {

        val projectContext = ProjectContext(environment.project)
        val sourceFiles = environment.getSourceFiles()


        val library = object : ModuleInfo {
            override val name: Name = Name.special("<library>")
            override fun dependencies(): List<ModuleInfo> = listOf(this)
        }
        val module = object : ModuleInfo {
            override val name: Name = Name.special("<module>")
            override fun dependencies(): List<ModuleInfo> = listOf(this, library)
        }

        val sourcesScope = createSourceModuleSearchScope(environment.project, sourceFiles)

        val builtIns = JvmBuiltIns(projectContext.storageManager)


        val javaRoots = classpath
                .mapNotNull {
                    val rootFile = when {
                        it.extension == "jar" ->
                            StandardFileSystems.jar().findFileByPath("${it.absolutePath}${URLUtil.JAR_SEPARATOR}")
                        else ->
                            StandardFileSystems.local().findFileByPath(it.absolutePath)
                    }

                    rootFile?.let { JavaRoot(it, JavaRoot.RootType.BINARY) }
                }

        val resolverForProject = ResolverForProjectImpl(
                "Dokka",
                projectContext,
                listOf(library, module),
                { JvmAnalyzerFacade },
                {
                    when (it) {
                        library -> ModuleContent(emptyList(), GlobalSearchScope.notScope(sourcesScope))
                        module -> ModuleContent(sourceFiles, sourcesScope)
                        else -> throw IllegalArgumentException("Unexpected module info")
                    }
                },
                JvmPlatformParameters {
                    val file = (it as JavaClassImpl).psi.containingFile.virtualFile
                    if (file in sourcesScope)
                        module
                    else
                        library
                },
                CompilerEnvironment,
                packagePartProviderFactory = { info, content ->
                    JvmPackagePartProvider(configuration.languageVersionSettings, content.moduleContentScope).apply {
                        addRoots(javaRoots)
                    }
                },
                builtIns = builtIns,
                modulePlatforms = { JvmPlatform.multiTargetPlatform }
        )

        resolverForProject.resolverForModule(library) // Required before module to initialize library properly
        val resolverForModule = resolverForProject.resolverForModule(module)
        val moduleDescriptor = resolverForProject.descriptorForModule(module)
        builtIns.initialize(moduleDescriptor, true)
        return DokkaResolutionFacade(environment.project, moduleDescriptor, resolverForModule)
    }

    fun loadLanguageVersionSettings(languageVersionString: String?, apiVersionString: String?) {
        val languageVersion = LanguageVersion.fromVersionString(languageVersionString) ?: LanguageVersion.LATEST_STABLE
        val apiVersion = apiVersionString?.let { ApiVersion.parse(it) } ?: ApiVersion.createByLanguageVersion(languageVersion)
        configuration.languageVersionSettings = LanguageVersionSettingsImpl(languageVersion, apiVersion)
    }

    /**
     * Classpath for this environment.
     */
    val classpath: List<File>
        get() = configuration.jvmClasspathRoots

    /**
     * Adds list of paths to classpath.
     * $paths: collection of files to add
     */
    fun addClasspath(paths: List<File>) {
        configuration.addJvmClasspathRoots(paths)
    }

    /**
     * Adds path to classpath.
     * $path: path to add
     */
    fun addClasspath(path: File) {
        configuration.addJvmClasspathRoot(path)
    }

    /**
     * List of source roots for this environment.
     */
    val sources: List<String>
        get() = configuration.get(JVMConfigurationKeys.CONTENT_ROOTS)
                ?.filterIsInstance<KotlinSourceRoot>()
                ?.map { it.path } ?: emptyList()

    /**
     * Adds list of paths to source roots.
     * $list: collection of files to add
     */
    fun addSources(list: List<String>) {
        list.forEach {
            configuration.addKotlinSourceRoot(it)
            val file = File(it)
            if (file.isDirectory || file.extension == ".java") {
                configuration.addJavaSourceRoot(file)
            }
        }
    }

    fun addRoots(list: List<ContentRoot>) {
        configuration.addAll(JVMConfigurationKeys.CONTENT_ROOTS, list)
    }

    /**
     * Disposes the environment and frees all associated resources.
     */
    override fun dispose() {
        Disposer.dispose(this)
    }
}

fun contentRootFromPath(path: String): ContentRoot {
    val file = File(path)
    return if (file.extension == "java") JavaSourceRoot(file, null) else KotlinSourceRoot(path)
}


class DokkaResolutionFacade(override val project: Project,
                            override val moduleDescriptor: ModuleDescriptor,
                            val resolverForModule: ResolverForModule) : ResolutionFacade {
    override fun <T : Any> tryGetFrontendService(element: PsiElement, serviceClass: Class<T>): T? {
        return null
    }

    override fun resolveToDescriptor(declaration: KtDeclaration, bodyResolveMode: BodyResolveMode): DeclarationDescriptor {
        return resolveSession.resolveToDescriptor(declaration)
    }

    override fun analyze(elements: Collection<KtElement>, bodyResolveMode: BodyResolveMode): BindingContext {
        throw UnsupportedOperationException()
    }

    val resolveSession: ResolveSession get() = getFrontendService(ResolveSession::class.java)

    override fun analyze(element: KtElement, bodyResolveMode: BodyResolveMode): BindingContext {
        throw UnsupportedOperationException()
    }

    override fun analyzeFullyAndGetResult(elements: Collection<KtElement>): AnalysisResult {
        throw UnsupportedOperationException()
    }

    override fun <T : Any> getFrontendService(element: PsiElement, serviceClass: Class<T>): T {
        throw UnsupportedOperationException()
    }

    override fun <T : Any> getFrontendService(serviceClass: Class<T>): T {
        return resolverForModule.componentProvider.getService(serviceClass)
    }

    override fun <T : Any> getFrontendService(moduleDescriptor: ModuleDescriptor, serviceClass: Class<T>): T {
        return resolverForModule.componentProvider.getService(serviceClass)
    }

    override fun <T : Any> getIdeService(serviceClass: Class<T>): T {
        throw UnsupportedOperationException()
    }

}