REPL System

/**
 * Compiler interface specialized for REPL snippet compilation
 */
interface ReplCompiler<CompiledSnippetT : Any> {
    /**
     * Compile a REPL snippet
     * @param snippet Source code snippet to compile
     * @param configuration Compilation configuration for the snippet
     * @return Result containing compiled snippet or compilation errors
     */
    suspend fun compile(
        snippet: SourceCode,
        configuration: ScriptCompilationConfiguration
    ): ResultWithDiagnostics<CompiledSnippetT>
}

/**
 * Evaluator interface specialized for REPL snippet evaluation
 */
interface ReplEvaluator<CompiledSnippetT : Any, EvaluatedSnippetT : Any> {
    /**
     * Evaluate a compiled REPL snippet
     * @param snippet Compiled snippet to evaluate
     * @param configuration Evaluation configuration
     * @return Result containing evaluated snippet or evaluation errors
     */
    suspend fun eval(
        snippet: CompiledSnippetT,
        configuration: ScriptEvaluationConfiguration
    ): ResultWithDiagnostics<EvaluatedSnippetT>
}

/**
 * Represents an evaluated REPL snippet
 */
interface EvaluatedSnippet {
    /** The compiled snippet that was evaluated */
    val compiledSnippet: CompiledSnippet
    /** Configuration used during evaluation */
    val configuration: ScriptEvaluationConfiguration
    /** Result of the evaluation */
    val result: ResultValue
}

/**
 * Unique identifier for REPL snippets
 */
interface ReplSnippetId {
    /** Sequence number of the snippet */
    val no: Int
    /** Generation number for versioning */
    val generation: Int
}

/**
 * Implementation of REPL snippet identifier
 */
data class ReplSnippetIdImpl(
    override val no: Int,
    override val generation: Int
) : ReplSnippetId

/**
 * Constants for REPL snippet numbering
 */
const val REPL_SNIPPET_FIRST_NO = 1
const val REPL_SNIPPET_FIRST_GEN = 1

/**
 * Interface for analyzing REPL code
 */
interface ReplCodeAnalyzer {
    /**
     * Analyze REPL code snippet
     * @param snippet Code snippet to analyze
     * @param cursor Cursor position within the snippet
     * @param configuration Analysis configuration
     * @return Analysis results
     */
    suspend fun analyze(
        snippet: SourceCode,
        cursor: SourceCode.Position,
        configuration: ScriptCompilationConfiguration
    ): ResultWithDiagnostics<ReplAnalyzerResult>
}

/**
 * Interface for providing code completion in REPL
 */
interface ReplCompleter {
    /**
     * Get code completion suggestions
     * @param snippet Code snippet for completion
     * @param cursor Cursor position for completion
     * @param configuration Compilation configuration
     * @return Sequence of completion variants
     */
    suspend fun complete(
        snippet: SourceCode,
        cursor: SourceCode.Position,
        configuration: ScriptCompilationConfiguration
    ): ResultWithDiagnostics<ReplCompletionResult>
}

/**
 * Type alias for completion results
 */
typealias ReplCompletionResult = Sequence<SourceCodeCompletionVariant>

/**
 * Individual completion suggestion
 */
data class SourceCodeCompletionVariant(
    val text: String,
    val displayText: String,
    val tail: String = "",
    val icon: String = "",
    val deprecationLevel: DeprecationLevel? = null
)

/**
 * Configuration keys specific to REPL compilation
 */
interface ReplScriptCompilationConfigurationKeys {
    val makeSnippetIdentifier: PropertiesCollection.Key<MakeSnippetIdentifier>
    val snippetIdKey: PropertiesCollection.Key<String>
}

/**
 * Configuration keys for REPL scripting host
 */
interface ReplScriptingHostConfigurationKeys {
    val replCompiler: PropertiesCollection.Key<ReplCompiler<*>>
    val replEvaluator: PropertiesCollection.Key<ReplEvaluator<*, *>>
    val replCodeAnalyzer: PropertiesCollection.Key<ReplCodeAnalyzer>
    val replCompleter: PropertiesCollection.Key<ReplCompleter>
}

/**
 * Keys for REPL analyzer results
 */
interface ReplAnalyzerResultKeys {
    val isComplete: PropertiesCollection.Key<Boolean>
    val completions: PropertiesCollection.Key<ReplCompletionResult>
    val diagnostics: PropertiesCollection.Key<List<ScriptDiagnostic>>
}

/**
 * Type alias for compiled snippet (same as CompiledScript)
 */
typealias CompiledSnippet = CompiledScript

/**
 * Function type for creating snippet identifiers
 */
typealias MakeSnippetIdentifier = (ReplSnippetId) -> String

/**
 * Results of REPL code analysis
 */
class ReplAnalyzerResult : PropertiesCollection

import kotlin.script.experimental.api.*

// Basic REPL implementation example
class SimpleReplSystem {
    private val compiler: ReplCompiler<CompiledSnippet> = TODO("Implementation")
    private val evaluator: ReplEvaluator<CompiledSnippet, EvaluatedSnippet> = TODO("Implementation")
    private val completer: ReplCompleter = TODO("Implementation")
    
    private var snippetCounter = REPL_SNIPPET_FIRST_NO
    private val evaluatedSnippets = mutableListOf<EvaluatedSnippet>()
    
    suspend fun execute(code: String): ReplResult {
        // Create snippet source
        val snippet = code.toScriptSource("snippet_$snippetCounter")
        
        // Compile the snippet
        val compilationResult = compiler.compile(snippet, getCompilationConfig())
        if (compilationResult is ResultWithDiagnostics.Failure) {
            return ReplResult.CompilationError(compilationResult.reports)
        }
        
        val compiledSnippet = compilationResult.value
        
        // Evaluate the snippet
        val evaluationResult = evaluator.eval(compiledSnippet, getEvaluationConfig())
        if (evaluationResult is ResultWithDiagnostics.Failure) {
            return ReplResult.EvaluationError(evaluationResult.reports)
        }
        
        val evaluatedSnippet = evaluationResult.value
        evaluatedSnippets.add(evaluatedSnippet)
        snippetCounter++
        
        return ReplResult.Success(evaluatedSnippet.result)
    }
    
    suspend fun complete(code: String, cursorPos: Int): List<String> {
        val snippet = code.toScriptSource("completion")
        val cursor = SourceCode.Position(1, cursorPos)
        
        val completionResult = completer.complete(snippet, cursor, getCompilationConfig())
        return if (completionResult is ResultWithDiagnostics.Success) {
            completionResult.value.map { it.text }.toList()
        } else {
            emptyList()
        }
    }
}

sealed class ReplResult {
    data class Success(val value: ResultValue) : ReplResult()
    data class CompilationError(val diagnostics: List<ScriptDiagnostic>) : ReplResult()
    data class EvaluationError(val diagnostics: List<ScriptDiagnostic>) : ReplResult()
}

// Snippet identifier management
class SnippetIdManager {
    private var currentNo = REPL_SNIPPET_FIRST_NO
    private var currentGen = REPL_SNIPPET_FIRST_GEN
    
    fun nextSnippetId(): ReplSnippetId {
        return ReplSnippetIdImpl(currentNo++, currentGen)
    }
    
    fun resetGeneration() {
        currentGen++
        currentNo = REPL_SNIPPET_FIRST_NO
    }
}

// Custom snippet identifier function
val customMakeSnippetIdentifier: MakeSnippetIdentifier = { snippetId ->
    "Snippet_${snippetId.no}_Gen${snippetId.generation}"
}

// REPL compilation configuration
val replCompilationConfig = ScriptCompilationConfiguration {
    makeSnippetIdentifier(customMakeSnippetIdentifier)
    snippetIdKey("replSnippetId")
    
    // Standard compilation settings
    defaultImports("kotlin.math.*", "kotlin.collections.*")
    dependencies.append(JvmDependency("org.jetbrains.kotlinx:kotlinx-coroutines-core:1.6.4"))
}

// Custom completion provider
class CustomReplCompleter : ReplCompleter {
    override suspend fun complete(
        snippet: SourceCode,
        cursor: SourceCode.Position,
        configuration: ScriptCompilationConfiguration
    ): ResultWithDiagnostics<ReplCompletionResult> {
        
        val text = snippet.text
        val cursorPos = cursor.absolutePos ?: return emptySequence<SourceCodeCompletionVariant>().asSuccess()
        
        // Simple keyword completion example
        val completions = mutableListOf<SourceCodeCompletionVariant>()
        
        // Get word at cursor
        val wordStart = text.lastIndexOf(' ', cursorPos - 1) + 1
        val prefix = text.substring(wordStart, cursorPos)
        
        // Kotlin keywords that start with prefix
        val keywords = listOf("fun", "val", "var", "if", "else", "when", "for", "while", "class", "interface")
        keywords.filter { it.startsWith(prefix) }.forEach { keyword ->
            completions.add(SourceCodeCompletionVariant(
                text = keyword,
                displayText = keyword,
                tail = " (keyword)",
                icon = "keyword"
            ))
        }
        
        return completions.asSequence().asSuccess()
    }
}

// Example REPL session flow
class InteractiveReplSession {
    private val replSystem = SimpleReplSystem()
    
    suspend fun runSession() {
        println("Kotlin REPL - Enter ':quit' to exit")
        
        while (true) {
            print("kotlin> ")
            val input = readLine() ?: break
            
            when {
                input == ":quit" -> break
                input.startsWith(":complete ") -> {
                    val code = input.removePrefix(":complete ")
                    val completions = replSystem.complete(code, code.length)
                    println("Completions: ${completions.joinToString(", ")}")
                }
                else -> {
                    when (val result = replSystem.execute(input)) {
                        is ReplResult.Success -> {
                            when (val value = result.value) {
                                is ResultValue.Value -> println("res: ${value.value}")
                                is ResultValue.Unit -> println("kotlin> ")
                                is ResultValue.Error -> println("Error: ${value.error.message}")
                                is ResultValue.NotEvaluated -> println("Not evaluated")
                            }
                        }
                        is ReplResult.CompilationError -> {
                            result.diagnostics.forEach {
                                println("Compilation error: ${it.message}")
                            }
                        }
                        is ReplResult.EvaluationError -> {
                            result.diagnostics.forEach {
                                println("Evaluation error: ${it.message}")
                            }
                        }
                    }
                }
            }
        }
    }
}