Host Integration

/**
 * Abstract base class for scripting hosts
 */
abstract class BasicScriptingHost {
    /**
     * Execute code within a coroutine context
     * @param body Suspend function to execute
     */
    open suspend fun runInCoroutineContext(body: suspend () -> Unit) = body()
    
    /**
     * Evaluate a script with compilation and evaluation configurations
     * @param script Source code to evaluate
     * @param compilationConfiguration Configuration for compilation
     * @param evaluationConfiguration Optional configuration for evaluation
     * @return Result of script evaluation
     */
    suspend fun eval(
        script: SourceCode,
        compilationConfiguration: ScriptCompilationConfiguration,
        evaluationConfiguration: ScriptEvaluationConfiguration? = null
    ): ResultWithDiagnostics<EvaluationResult>
}

/**
 * Configuration for scripting host
 */
class ScriptingHostConfiguration : PropertiesCollection {
    companion object {
        val Default = ScriptingHostConfiguration()
    }
}

/**
 * Complete definition of a script type with compilation and evaluation configurations
 */
data class ScriptDefinition(
    val compilationConfiguration: ScriptCompilationConfiguration,
    val evaluationConfiguration: ScriptEvaluationConfiguration
)

/**
 * Create script definition from annotated template class
 * @param template Class annotated with @KotlinScript
 * @param hostConfiguration Optional host configuration
 * @return Script definition with resolved configurations
 */
fun createScriptDefinitionFromTemplate(
    template: KClass<out Any>,
    hostConfiguration: ScriptingHostConfiguration = ScriptingHostConfiguration.Default
): ScriptDefinition

/**
 * Create compilation configuration from template class
 * @param template Class annotated with @KotlinScript
 * @param hostConfiguration Optional host configuration
 * @return Resolved compilation configuration
 */
fun createCompilationConfigurationFromTemplate(
    template: KClass<out Any>,
    hostConfiguration: ScriptingHostConfiguration = ScriptingHostConfiguration.Default
): ScriptCompilationConfiguration

/**
 * Create evaluation configuration from template class
 * @param template Class annotated with @KotlinScript
 * @param hostConfiguration Optional host configuration
 * @return Resolved evaluation configuration
 */
fun createEvaluationConfigurationFromTemplate(
    template: KClass<out Any>,
    hostConfiguration: ScriptingHostConfiguration = ScriptingHostConfiguration.Default
): ScriptEvaluationConfiguration

/**
 * Abstract base class for file-based script sources
 */
abstract class FileBasedScriptSource : ExternalSourceCode {
    /** The file containing the script source */
    abstract val file: File
    
    override val text: String get() = file.readText()
    override val name: String? get() = file.name
    override val locationId: String? get() = file.absolutePath
}

/**
 * Script source backed by a file
 */
class FileScriptSource(override val file: File) : FileBasedScriptSource() {
    override val externalLocation: String? get() = file.absolutePath
}

/**
 * Script source backed by a URL
 */
class UrlScriptSource(
    private val url: URL,
    override val text: String
) : ExternalSourceCode {
    override val name: String? get() = url.file.substringAfterLast('/')
    override val locationId: String? get() = url.toString()
    override val externalLocation: String? get() = url.toString()
}

/**
 * Script source backed by a string
 */
class StringScriptSource(
    override val text: String,
    override val name: String? = null
) : SourceCode {
    override val locationId: String? = name
}

/**
 * Configuration keys for scripting host
 */
interface ScriptingHostConfigurationKeys {
    val jvmTarget: PropertiesCollection.Key<String>
    val getScriptingClass: PropertiesCollection.Key<GetScriptingClass>
    val configurationDependencies: PropertiesCollection.Key<List<ScriptDependency>>
}

/**
 * Interface for loading classes in the scripting environment
 */
interface GetScriptingClass {
    /**
     * Load a class by name
     * @param className Fully qualified class name
     * @return Loaded class or null if not found
     */
    operator fun invoke(className: String): KClass<*>?
}

/**
 * Convert File to script source
 */
fun File.toScriptSource(): FileScriptSource

/**
 * Convert String to script source with optional name
 */
fun String.toScriptSource(name: String? = null): StringScriptSource

/**
 * Get scripting class loader from host configuration
 */
fun ScriptingHostConfiguration.getScriptingClass(): GetScriptingClass?

import kotlin.script.experimental.host.*
import kotlin.script.experimental.api.*

// Custom scripting host implementation
class MyScriptingHost : BasicScriptingHost() {
    private val compiler: ScriptCompiler = TODO("Implementation")
    private val evaluator: ScriptEvaluator = TODO("Implementation")
    
    override suspend fun runInCoroutineContext(body: suspend () -> Unit) {
        // Custom coroutine context setup
        withContext(Dispatchers.IO) {
            body()
        }
    }
    
    suspend fun executeScript(scriptFile: File): ResultWithDiagnostics<Any?> {
        val source = scriptFile.toScriptSource()
        val compilationConfig = ScriptCompilationConfiguration {
            defaultImports("kotlin.math.*")
        }
        val evaluationConfig = ScriptEvaluationConfiguration.Default
        
        return eval(source, compilationConfig, evaluationConfig).map { result ->
            when (val returnValue = result.returnValue) {
                is ResultValue.Value -> returnValue.value
                is ResultValue.Unit -> Unit
                is ResultValue.Error -> throw returnValue.error
                is ResultValue.NotEvaluated -> null
            }
        }
    }
}

// Using the custom host
val host = MyScriptingHost()
val scriptFile = File("script.kts")

runBlocking {
    when (val result = host.executeScript(scriptFile)) {
        is ResultWithDiagnostics.Success -> {
            println("Script result: ${result.value}")
        }
        is ResultWithDiagnostics.Failure -> {
            result.reports.forEach { diagnostic ->
                println("${diagnostic.severity}: ${diagnostic.message}")
            }
        }
    }
}

// Define a script template
@KotlinScript(
    displayName = "Data Processing Script",
    fileExtension = "data.kts",
    compilationConfiguration = DataScriptCompilationConfig::class,
    evaluationConfiguration = DataScriptEvaluationConfig::class
)
abstract class DataScript

class DataScriptCompilationConfig : ScriptCompilationConfiguration({
    defaultImports("kotlin.collections.*", "kotlin.io.*")
    dependencies.append(JvmDependency("org.apache.commons:commons-csv:1.9.0"))
})

class DataScriptEvaluationConfig : ScriptEvaluationConfiguration({
    contextVariables.put("dataDir", File("./data"))
})

// Create script definition from template
val scriptDefinition = createScriptDefinitionFromTemplate(DataScript::class)

// Use the definition
val host = MyScriptingHost()
val script = File("process-data.data.kts").toScriptSource()

val result = host.eval(
    script,
    scriptDefinition.compilationConfiguration,
    scriptDefinition.evaluationConfiguration
)

// Custom class loader for scripting
class CustomScriptingClassLoader : GetScriptingClass {
    private val additionalClassPath = mutableListOf<URL>()
    
    fun addToClassPath(url: URL) {
        additionalClassPath.add(url)
    }
    
    override fun invoke(className: String): KClass<*>? {
        return try {
            val classLoader = URLClassLoader(additionalClassPath.toTypedArray())
            Class.forName(className, false, classLoader).kotlin
        } catch (e: ClassNotFoundException) {
            null
        }
    }
}

// Host configuration with custom class loader
val customClassLoader = CustomScriptingClassLoader().apply {
    addToClassPath(File("lib/custom.jar").toURI().toURL())
}

val hostConfig = ScriptingHostConfiguration {
    getScriptingClass(customClassLoader)
    jvmTarget("1.8")
    configurationDependencies(listOf(
        JvmDependency("org.jetbrains.kotlin:kotlin-scripting-jvm:1.8.0")
    ))
}

// Create configurations with custom host config
val compilationConfig = createCompilationConfigurationFromTemplate(
    DataScript::class,
    hostConfig
)

val evaluationConfig = createEvaluationConfigurationFromTemplate(
    DataScript::class,
    hostConfig
)

// Various ways to create script sources
val fileSource = File("script.kts").toScriptSource()
val stringSource = "println(\"Hello World\")".toScriptSource("hello.kts")

// URL-based script source
val url = URL("https://example.com/script.kts")
val urlText = url.readText()
val urlSource = UrlScriptSource(url, urlText)

// Custom script source with caching
class CachedFileScriptSource(override val file: File) : FileBasedScriptSource() {
    private var cachedText: String? = null
    private var lastModified: Long = 0
    
    override val text: String
        get() {
            val currentModified = file.lastModified()
            if (cachedText == null || currentModified > lastModified) {
                cachedText = file.readText()
                lastModified = currentModified
            }
            return cachedText!!
        }
    
    override val externalLocation: String? get() = file.absolutePath
}

// Database-backed script source
class DatabaseScriptSource(
    private val scriptId: String,
    private val database: ScriptDatabase
) : ExternalSourceCode {
    override val text: String by lazy { database.getScriptContent(scriptId) }
    override val name: String? = "script_$scriptId"
    override val locationId: String? = "db:$scriptId"
    override val externalLocation: String? = "database://scripts/$scriptId"
}

// Plugin-based scripting system
class PluginScriptingHost : BasicScriptingHost() {
    private val plugins = mutableMapOf<String, ScriptPlugin>()
    
    fun registerPlugin(name: String, plugin: ScriptPlugin) {
        plugins[name] = plugin
    }
    
    suspend fun executeWithPlugins(script: SourceCode): ResultWithDiagnostics<Any?> {
        // Pre-execution plugin hooks
        plugins.values.forEach { it.beforeExecution(script) }
        
        val result = eval(script, getCompilationConfig(), getEvaluationConfig())
        
        // Post-execution plugin hooks
        plugins.values.forEach { it.afterExecution(script, result) }
        
        return result.map { evaluationResult ->
            when (val returnValue = evaluationResult.returnValue) {
                is ResultValue.Value -> returnValue.value
                else -> null
            }
        }
    }
}

interface ScriptPlugin {
    suspend fun beforeExecution(script: SourceCode)
    suspend fun afterExecution(script: SourceCode, result: ResultWithDiagnostics<EvaluationResult>)
}

// Service-based scripting host
class ServiceBasedScriptingHost(
    private val compiler: ScriptCompiler,
    private val evaluator: ScriptEvaluator,
    private val logger: Logger
) : BasicScriptingHost() {
    
    override suspend fun runInCoroutineContext(body: suspend () -> Unit) {
        logger.info("Starting script execution")
        try {
            withTimeout(30000) { // 30 second timeout
                body()
            }
        } catch (e: TimeoutCancellationException) {
            logger.error("Script execution timed out")
            throw e
        } finally {
            logger.info("Script execution completed")
        }
    }
}