/**
 * Copyright 2010 JogAmp Community. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without modification, are
 * permitted provided that the following conditions are met:
 *
 *    1. Redistributions of source code must retain the above copyright notice, this list of
 *       conditions and the following disclaimer.
 *
 *    2. Redistributions in binary form must reproduce the above copyright notice, this list
 *       of conditions and the following disclaimer in the documentation and/or other materials
 *       provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY JogAmp Community ``AS IS'' AND ANY EXPRESS OR IMPLIED
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
 * FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL JogAmp Community OR
 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
 * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 * The views and conclusions contained in the software and documentation are those of the
 * authors and should not be interpreted as representing official policies, either expressed
 * or implied, of JogAmp Community.
 */

package jogamp.common.os;

import com.jogamp.common.os.MachineDescription;
import com.jogamp.common.os.Platform;
import com.jogamp.common.os.MachineDescription.StaticConfig;

/**
 * Runtime MachineDescription
 */
public class MachineDescriptionRuntime {

  static volatile boolean smdHardQueried = false;
  static MachineDescription.StaticConfig smdHard = null;

  static volatile boolean smdSoftQueried = false;
  static MachineDescription.StaticConfig smdSoft = null;

  static volatile boolean smdHardEnabled = false;

  /* pp */ static void notifyPropsInitialized() { smdHardEnabled = true; }

  public static MachineDescription.StaticConfig getStatic() {
      if(!smdHardEnabled) {
          if(!smdSoftQueried) {
              synchronized(MachineDescription.class) { // volatile dbl-checked-locking OK
                  if(!smdSoftQueried) {
                      smdSoft = get(PlatformPropsImpl.OS_TYPE, PlatformPropsImpl.sCpuType, PlatformPropsImpl.LITTLE_ENDIAN);
                      smdSoftQueried=true;
                  }
              }
          }
          return smdSoft;
      } else {
          if(!smdHardQueried) {
              synchronized(MachineDescription.class) { // volatile dbl-checked-locking OK
                  if(!smdHardQueried) {
                      smdHard = get(PlatformPropsImpl.OS_TYPE, PlatformPropsImpl.CPU_ARCH, PlatformPropsImpl.LITTLE_ENDIAN);
                      smdHardQueried=true;
                  }
              }
          }
          return smdHard;
      }
  }

  private static boolean isCPUArch32Bit(final Platform.CPUType cpuType) throws RuntimeException {
    switch( cpuType ) {
        case X86_32:
        case ARM:
        case ARMv5:
        case ARMv6:
        case ARMv7:
        case SPARC_32:
        case PPC:
            return true;
        case X86_64:
        case IA64:
        case SPARCV9_64:
        case PA_RISC2_0:
            return false;
        default:
            throw new RuntimeException("Please port CPU detection (32/64 bit) to your platform (" + PlatformPropsImpl.OS_lower + "/" + PlatformPropsImpl.ARCH_lower + "("+PlatformPropsImpl.CPU_ARCH+"))");
    }
  }

  private static MachineDescription.StaticConfig get(final Platform.OSType osType, final Platform.CPUType cpuType, final boolean littleEndian) {
      if( isCPUArch32Bit(cpuType) ) {
          if( cpuType.getFamily() == Platform.CPUFamily.ARM && littleEndian) {
              return StaticConfig.ARMle_EABI;
          } else if( osType == Platform.OSType.WINDOWS ) {
              return StaticConfig.X86_32_WINDOWS;
          } else if( osType == Platform.OSType.MACOS ) {
              return StaticConfig.X86_32_MACOS;
          } else if ( osType == Platform.OSType.SUNOS ) {
              if ( cpuType == Platform.CPUType.SPARC_32 ) {
                  return StaticConfig.SPARC_32_SUNOS;
              }
              // TODO SPARCv9 description is missing
          }
          return StaticConfig.X86_32_UNIX;
      } else {
          if( osType == Platform.OSType.WINDOWS ) {
              return StaticConfig.X86_64_WINDOWS;
          }
          return StaticConfig.X86_64_UNIX;
      }
  }

  static volatile boolean rmdQueried = false;
  static MachineDescription rmd = null;

  public static MachineDescription getRuntime() {
        if(!rmdQueried) {
            synchronized(MachineDescription.class) { // volatile dbl-checked-locking OK
                if(!rmdQueried) {
                    rmd = getRuntimeImpl();
                    rmdQueried=true;
                }
            }
        }
        return rmd;
  }
  private static MachineDescription getRuntimeImpl() {
        try {
            Platform.initSingleton(); // loads native gluegen-rt library
        } catch (final UnsatisfiedLinkError err) {
            return null;
        }

        final int pointerSizeInBytes = getPointerSizeInBytesImpl();
        switch(pointerSizeInBytes) {
            case 4:
            case 8:
                break;
            default:
                throw new RuntimeException("Unsupported pointer size "+pointerSizeInBytes+"bytes, please implement.");
        }

        final long pageSizeL =  getPageSizeInBytesImpl();
        if(Integer.MAX_VALUE < pageSizeL) {
            throw new InternalError("PageSize exceeds integer value: " + pageSizeL);
        }

        // size:      int, long, float, double, pointer, pageSize
        // alignment: int8, int16, int32, int64, int, long, float, double, pointer
        return new MachineDescription(
            true /* runtime validated */, PlatformPropsImpl.LITTLE_ENDIAN,

            getSizeOfIntImpl(), getSizeOfLongImpl(),
            getSizeOfFloatImpl(), getSizeOfDoubleImpl(), getSizeOfLongDoubleImpl(),
            pointerSizeInBytes, (int)pageSizeL,

            getAlignmentInt8Impl(), getAlignmentInt16Impl(), getAlignmentInt32Impl(), getAlignmentInt64Impl(),
            getAlignmentIntImpl(), getAlignmentLongImpl(),
            getAlignmentFloatImpl(), getAlignmentDoubleImpl(), getAlignmentLongDoubleImpl(),
            getAlignmentPointerImpl());
    }

    private static native int getPointerSizeInBytesImpl();
    private static native long getPageSizeInBytesImpl();

    private static native int getAlignmentInt8Impl();
    private static native int getAlignmentInt16Impl();
    private static native int getAlignmentInt32Impl();
    private static native int getAlignmentInt64Impl();
    private static native int getAlignmentIntImpl();
    private static native int getAlignmentLongImpl();
    private static native int getAlignmentPointerImpl();
    private static native int getAlignmentFloatImpl();
    private static native int getAlignmentDoubleImpl();
    private static native int getAlignmentLongDoubleImpl();
    private static native int getSizeOfIntImpl();
    private static native int getSizeOfLongImpl();
    private static native int getSizeOfPointerImpl();
    private static native int getSizeOfFloatImpl();
    private static native int getSizeOfDoubleImpl();
    private static native int getSizeOfLongDoubleImpl();
}