package dev.openrs2.util.io

import java.io.BufferedWriter
import java.io.OutputStream
import java.nio.channels.FileChannel
import java.nio.charset.Charset
import java.nio.file.CopyOption
import java.nio.file.FileVisitOption
import java.nio.file.Files
import java.nio.file.LinkOption
import java.nio.file.OpenOption
import java.nio.file.Path
import java.nio.file.StandardCopyOption
import java.nio.file.StandardOpenOption
import java.nio.file.attribute.FileAttribute

fun Path.fsync() {
    require(Files.isRegularFile(this) || Files.isDirectory(this))

    FileChannel.open(this, StandardOpenOption.READ).use { channel ->
        channel.force(true)
    }
}

fun Path.recursiveCopy(
    destination: Path,
    visitOptions: Array<FileVisitOption> = emptyArray(),
    copyOptions: Array<CopyOption> = emptyArray()
) {
    for (sourceFile in Files.walk(this, *visitOptions)) {
        val destinationFile = destination.resolve(this.relativize(sourceFile).toString())

        if (Files.isDirectory(sourceFile)) {
            Files.createDirectory(destinationFile)
        } else {
            Files.copy(sourceFile, destinationFile, *copyOptions)
        }
    }
}

fun Path.recursiveEquals(
    other: Path,
    linkOptions: Array<LinkOption> = emptyArray(),
    openOptions: Array<OpenOption> = emptyArray()
): Boolean {
    val list1 = Files.newDirectoryStream(this).use { stream ->
        stream.map { this.relativize(it).toString() }.sorted().toList()
    }

    val list2 = Files.newDirectoryStream(other).use { stream ->
        stream.map { other.relativize(it).toString() }.sorted().toList()
    }

    if (list1 != list2) {
        return false
    }

    for (file in list1) {
        val file1 = this.resolve(file)
        val file2 = other.resolve(file)

        if (Files.isDirectory(file1, *linkOptions)) {
            if (!Files.isDirectory(file2, *linkOptions)) {
                return false
            }
        } else {
            Files.newInputStream(file1, *openOptions).use { input1 ->
                Files.newInputStream(file2, *openOptions).use { input2 ->
                    if (!input1.contentEquals(input2)) {
                        return false
                    }
                }
            }
        }
    }

    return true
}

inline fun <T> useTempFile(
    prefix: String? = null,
    suffix: String? = null,
    vararg attributes: FileAttribute<*>,
    f: (Path) -> T
): T {
    val tempFile = Files.createTempFile(prefix, suffix, *attributes)
    try {
        return f(tempFile)
    } finally {
        Files.deleteIfExists(tempFile)
    }
}

inline fun <T> Path.useTempFile(
    prefix: String? = null,
    suffix: String? = null,
    vararg attributes: FileAttribute<*>,
    f: (Path) -> T
): T {
    val tempFile = Files.createTempFile(this, prefix, suffix, *attributes)
    try {
        return f(tempFile)
    } finally {
        Files.deleteIfExists(tempFile)
    }
}

inline fun <T> Path.atomicWrite(f: (Path) -> T): T {
    val tempFile = Files.createTempFile(parent, ".$fileName", ".tmp")
    try {
        val result = f(tempFile)
        Files.move(tempFile, this, StandardCopyOption.ATOMIC_MOVE, StandardCopyOption.REPLACE_EXISTING)
        return result
    } finally {
        Files.deleteIfExists(tempFile)
    }
}

inline fun <T> Path.useAtomicBufferedWriter(vararg options: OpenOption, f: (BufferedWriter) -> T): T {
    return atomicWrite { path ->
        Files.newBufferedWriter(path, *options).use { writer ->
            f(writer)
        }
    }
}

inline fun <T> Path.useAtomicBufferedWriter(cs: Charset, vararg options: OpenOption, f: (BufferedWriter) -> T): T {
    return atomicWrite { path ->
        Files.newBufferedWriter(path, cs, *options).use { writer ->
            f(writer)
        }
    }
}

inline fun <T> Path.useAtomicOutputStream(vararg options: OpenOption, f: (OutputStream) -> T): T {
    return atomicWrite { path ->
        Files.newOutputStream(path, *options).use { output ->
            f(output)
        }
    }
}