package com.infendro.cli.command.context

import com.infendro.cli.Dsl
import com.infendro.cli.command.Argument
import com.infendro.cli.command.Command
import com.infendro.cli.command.Option
import kotlin.reflect.KProperty

@Dsl
class Context internal constructor(
    val command: Command,
    val commands: List<Cmd>,
    val arguments: List<Arg>,
    val options: List<Opt>,
) {
    class Cmd(
        val name: String,
    )

    class Arg(
        val value: Any,
    )

    class Opt(
        val name: String,
        val value: Any,
    )

    internal fun execute() = (command.execute)()

    fun help() {
        command.help?.let { println(it) }
    }

    operator fun Command.Key.getValue(thisRef: Any?, property: KProperty<*>): String = commands[index].name

    private val <T : Any> Argument<T>.index: Int
        get() = command.arguments.takeWhile { it != this }.sumOf { it.count }

    @Suppress("UNCHECKED_CAST")
    private val <T : Any> Argument<T>.value: T?
        get() = arguments.getOrNull(index)?.value as? T

    @Suppress("UNCHECKED_CAST")
    private val <T : Any> Argument.Variable<T>.values: List<T>
        get() = arguments.drop(index).take(count).map { it.value as T }

    operator fun <T : Any> Argument.Required<T>.getValue(thisRef: Any?, property: KProperty<*>): T = value!!
    operator fun <T : Any> Argument.OrElse<T>.getValue(thisRef: Any?, property: KProperty<*>): T = value ?: other
    operator fun <T : Any> Argument.OrNull<T>.getValue(thisRef: Any?, property: KProperty<*>): T? = value
    operator fun <T : Any> Argument.Variable<T>.getValue(thisRef: Any?, property: KProperty<*>): List<T> = values

    @Suppress("UNCHECKED_CAST")
    private val <T : Any> Option<T>.value: T?
        get() = options.firstOrNull { it.name in names }?.value as? T

    @Suppress("UNCHECKED_CAST")
    private val <T : Any> Option.Variable<T>.values: List<T>
        get() = options.filter { it.name in names }.map { it.value as T }

    operator fun <T : Any> Option.Required<T>.getValue(thisRef: Any?, property: KProperty<*>): T = value!!
    operator fun <T : Any> Option.OrElse<T>.getValue(thisRef: Any?, property: KProperty<*>): T = value ?: other
    operator fun <T : Any> Option.OrNull<T>.getValue(thisRef: Any?, property: KProperty<*>): T? = value
    operator fun <T : Any> Option.Variable<T>.getValue(thisRef: Any?, property: KProperty<*>): List<T> = values
}