/*
 * Copyright (c) 2021 AtLarge Research
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in all
 * copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */

package org.opendc.harness.internal

import org.opendc.harness.api.Parameter
import org.opendc.harness.dsl.Experiment
import kotlin.properties.ReadOnlyProperty
import kotlin.reflect.KProperty

/**
 * A delegate for an experiment parameter.
 *
 * @property parameter The parameter descriptor of this delegate.
 */
internal class ParameterDelegate<T>(val parameter: Parameter<T>) : ReadOnlyProperty<Experiment, T> {
    /**
     * Obtain the value for the parameter.
     */
    override fun getValue(thisRef: Experiment, property: KProperty<*>): T {
        val scenario = thisRef.scenario ?: throw IllegalStateException("Cannot use parameters before activation")
        return scenario[parameter]
    }
}