/*
 * Copyright (C) 2014 Square, Inc.
 *
 * 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 okio

import okio.internal.commonClose
import okio.internal.commonExhausted
import okio.internal.commonIndexOf
import okio.internal.commonIndexOfElement
import okio.internal.commonPeek
import okio.internal.commonRangeEquals
import okio.internal.commonRead
import okio.internal.commonReadAll
import okio.internal.commonReadByte
import okio.internal.commonReadByteArray
import okio.internal.commonReadByteString
import okio.internal.commonReadDecimalLong
import okio.internal.commonReadFully
import okio.internal.commonReadHexadecimalUnsignedLong
import okio.internal.commonReadInt
import okio.internal.commonReadIntLe
import okio.internal.commonReadLong
import okio.internal.commonReadLongLe
import okio.internal.commonReadShort
import okio.internal.commonReadShortLe
import okio.internal.commonReadUtf8
import okio.internal.commonReadUtf8CodePoint
import okio.internal.commonReadUtf8Line
import okio.internal.commonReadUtf8LineStrict
import okio.internal.commonRequest
import okio.internal.commonRequire
import okio.internal.commonSelect
import okio.internal.commonSkip
import okio.internal.commonTimeout
import okio.internal.commonToString
import java.io.IOException
import java.io.InputStream
import java.nio.ByteBuffer
import java.nio.charset.Charset

internal actual class RealBufferedSource actual constructor(
  @JvmField actual val source: Source
) : BufferedSource {
  @JvmField val bufferField = Buffer()
  @JvmField actual var closed: Boolean = false

  @Suppress("OVERRIDE_BY_INLINE") // Prevent internal code from calling the getter.
  override val buffer: Buffer
    inline get() = bufferField

  override fun buffer() = bufferField

  override fun read(sink: Buffer, byteCount: Long): Long = commonRead(sink, byteCount)
  override fun exhausted(): Boolean = commonExhausted()
  override fun require(byteCount: Long): Unit = commonRequire(byteCount)
  override fun request(byteCount: Long): Boolean = commonRequest(byteCount)
  override fun readByte(): Byte = commonReadByte()
  override fun readByteString(): ByteString = commonReadByteString()
  override fun readByteString(byteCount: Long): ByteString = commonReadByteString(byteCount)
  override fun select(options: Options): Int = commonSelect(options)
  override fun readByteArray(): ByteArray = commonReadByteArray()
  override fun readByteArray(byteCount: Long): ByteArray = commonReadByteArray(byteCount)
  override fun read(sink: ByteArray): Int = read(sink, 0, sink.size)
  override fun readFully(sink: ByteArray): Unit = commonReadFully(sink)
  override fun read(sink: ByteArray, offset: Int, byteCount: Int): Int =
    commonRead(sink, offset, byteCount)

  override fun read(sink: ByteBuffer): Int {
    if (buffer.size == 0L) {
      val read = source.read(buffer, Segment.SIZE.toLong())
      if (read == -1L) return -1
    }

    return buffer.read(sink)
  }

  override fun readFully(sink: Buffer, byteCount: Long): Unit = commonReadFully(sink, byteCount)
  override fun readAll(sink: Sink): Long = commonReadAll(sink)
  override fun readUtf8(): String = commonReadUtf8()
  override fun readUtf8(byteCount: Long): String = commonReadUtf8(byteCount)

  override fun readString(charset: Charset): String {
    buffer.writeAll(source)
    return buffer.readString(charset)
  }

  override fun readString(byteCount: Long, charset: Charset): String {
    require(byteCount)
    return buffer.readString(byteCount, charset)
  }

  override fun readUtf8Line(): String? = commonReadUtf8Line()
  override fun readUtf8LineStrict() = readUtf8LineStrict(Long.MAX_VALUE)
  override fun readUtf8LineStrict(limit: Long): String = commonReadUtf8LineStrict(limit)
  override fun readUtf8CodePoint(): Int = commonReadUtf8CodePoint()
  override fun readShort(): Short = commonReadShort()
  override fun readShortLe(): Short = commonReadShortLe()
  override fun readInt(): Int = commonReadInt()
  override fun readIntLe(): Int = commonReadIntLe()
  override fun readLong(): Long = commonReadLong()
  override fun readLongLe(): Long = commonReadLongLe()
  override fun readDecimalLong(): Long = commonReadDecimalLong()
  override fun readHexadecimalUnsignedLong(): Long = commonReadHexadecimalUnsignedLong()
  override fun skip(byteCount: Long): Unit = commonSkip(byteCount)
  override fun indexOf(b: Byte): Long = indexOf(b, 0L, Long.MAX_VALUE)
  override fun indexOf(b: Byte, fromIndex: Long): Long = indexOf(b, fromIndex, Long.MAX_VALUE)
  override fun indexOf(b: Byte, fromIndex: Long, toIndex: Long): Long =
    commonIndexOf(b, fromIndex, toIndex)

  override fun indexOf(bytes: ByteString): Long = indexOf(bytes, 0L)
  override fun indexOf(bytes: ByteString, fromIndex: Long): Long = commonIndexOf(bytes, fromIndex)
  override fun indexOfElement(targetBytes: ByteString): Long = indexOfElement(targetBytes, 0L)
  override fun indexOfElement(targetBytes: ByteString, fromIndex: Long): Long =
    commonIndexOfElement(targetBytes, fromIndex)

  override fun rangeEquals(offset: Long, bytes: ByteString) = rangeEquals(
    offset, bytes, 0,
    bytes.size
  )

  override fun rangeEquals(
    offset: Long,
    bytes: ByteString,
    bytesOffset: Int,
    byteCount: Int
  ): Boolean = commonRangeEquals(offset, bytes, bytesOffset, byteCount)

  override fun peek(): BufferedSource = commonPeek()

  override fun inputStream(): InputStream {
    return object : InputStream() {
      override fun read(): Int {
        if (closed) throw IOException("closed")
        if (buffer.size == 0L) {
          val count = source.read(buffer, Segment.SIZE.toLong())
          if (count == -1L) return -1
        }
        return buffer.readByte() and 0xff
      }

      override fun read(data: ByteArray, offset: Int, byteCount: Int): Int {
        if (closed) throw IOException("closed")
        checkOffsetAndCount(data.size.toLong(), offset.toLong(), byteCount.toLong())

        if (buffer.size == 0L) {
          val count = source.read(buffer, Segment.SIZE.toLong())
          if (count == -1L) return -1
        }

        return buffer.read(data, offset, byteCount)
      }

      override fun available(): Int {
        if (closed) throw IOException("closed")
        return minOf(buffer.size, Integer.MAX_VALUE).toInt()
      }

      override fun close() = this@RealBufferedSource.close()

      override fun toString() = "${this@RealBufferedSource}.inputStream()"
    }
  }

  override fun isOpen() = !closed

  override fun close(): Unit = commonClose()
  override fun timeout(): Timeout = commonTimeout()
  override fun toString(): String = commonToString()
}