// Copyright 2021 Code Intelligence GmbH
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//      http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

package com.code_intelligence.jazzer.instrumentor

import java.io.FileOutputStream

object PatchTestUtils {
    @JvmStatic
    fun classToBytecode(targetClass: Class<*>): ByteArray {
        return ClassLoader
            .getSystemClassLoader()
            .getResourceAsStream("${targetClass.name.replace('.', '/')}.class")!!
            .use {
                it.readBytes()
            }
    }

    @JvmStatic
    fun bytecodeToClass(name: String, bytecode: ByteArray): Class<*> {
        return BytecodeClassLoader(name, bytecode).loadClass(name)
    }

    @JvmStatic
    fun dumpBytecode(outDir: String, name: String, originalBytecode: ByteArray) {
        FileOutputStream("$outDir/$name.class").use { fos -> fos.write(originalBytecode) }
    }

    /**
     * A ClassLoader that dynamically loads a single specified class from byte code and delegates all other class loads to
     * its own ClassLoader.
     */
    class BytecodeClassLoader(val className: String, private val classBytecode: ByteArray) :
        ClassLoader(BytecodeClassLoader::class.java.classLoader) {
        override fun loadClass(name: String): Class<*> {
            if (name != className) {
                return super.loadClass(name)
            }
            return defineClass(className, classBytecode, 0, classBytecode.size)
        }
    }
}

fun assertSelfCheck(target: DynamicTestContract, shouldPass: Boolean = true) {
    val results = target.selfCheck()
    for ((test, passed) in results) {
        if (shouldPass) {
            assert(passed) { "$test should pass" }
        } else {
            assert(!passed) { "$test should not pass" }
        }
    }
}