/*
 
  This Source Code Form is subject to the terms of the Mozilla Public
  License, v. 2.0. If a copy of the MPL was not distributed with this
  file, You can obtain one at http://mozilla.org/MPL/2.0/.
 
  Copyright (C) 2009-2013 Michael Möller <mmoeller@openhardwaremonitor.org>
	
*/

using System;
using System.Collections.Generic;
using System.Globalization;
using System.Text;
using System.Threading;

namespace OpenHardwareMonitor.Hardware.LPC {
  internal class LPCIO {

    private readonly List<ISuperIO> superIOs = new List<ISuperIO>();
    private readonly StringBuilder report = new StringBuilder();

    // I/O Ports
    private readonly ushort[] REGISTER_PORTS = new ushort[] { 0x2E, 0x4E };
    private readonly ushort[] VALUE_PORTS = new ushort[] { 0x2F, 0x4F };

    private ushort registerPort;
    private ushort valuePort;

    // Registers
    private const byte CONFIGURATION_CONTROL_REGISTER = 0x02;
    private const byte DEVCIE_SELECT_REGISTER = 0x07;
    private const byte CHIP_ID_REGISTER = 0x20;
    private const byte CHIP_REVISION_REGISTER = 0x21;
    private const byte BASE_ADDRESS_REGISTER = 0x60;

    private byte ReadByte(byte register) {
      Ring0.WriteIoPort(registerPort, register);
      return Ring0.ReadIoPort(valuePort);
    }

    private void WriteByte(byte register, byte value) {
      Ring0.WriteIoPort(registerPort, register);
      Ring0.WriteIoPort(valuePort, value);
    }

    private ushort ReadWord(byte register) {
      return (ushort)((ReadByte(register) << 8) |
        ReadByte((byte)(register + 1)));
    }

    private void Select(byte logicalDeviceNumber) {
      Ring0.WriteIoPort(registerPort, DEVCIE_SELECT_REGISTER);
      Ring0.WriteIoPort(valuePort, logicalDeviceNumber);
    }

    private void ReportUnknownChip(string type, int chip) {
      report.Append("Chip ID: Unknown ");
      report.Append(type);
      report.Append(" with ID 0x");
      report.Append(chip.ToString("X", CultureInfo.InvariantCulture));
      report.Append(" at 0x");
      report.Append(registerPort.ToString("X", CultureInfo.InvariantCulture));
      report.Append("/0x");
      report.AppendLine(valuePort.ToString("X", CultureInfo.InvariantCulture));
      report.AppendLine();
    }

    #region Winbond, Nuvoton, Fintek

    private const byte FINTEK_VENDOR_ID_REGISTER = 0x23;
    private const ushort FINTEK_VENDOR_ID = 0x1934;

    private const byte WINBOND_NUVOTON_HARDWARE_MONITOR_LDN = 0x0B;

    private const byte F71858_HARDWARE_MONITOR_LDN = 0x02;
    private const byte FINTEK_HARDWARE_MONITOR_LDN = 0x04;

    private const byte NUVOTON_HARDWARE_MONITOR_IO_SPACE_LOCK = 0x28;

    private void WinbondNuvotonFintekEnter() {
      Ring0.WriteIoPort(registerPort, 0x87);
      Ring0.WriteIoPort(registerPort, 0x87);
    }

    private void WinbondNuvotonFintekExit() {
      Ring0.WriteIoPort(registerPort, 0xAA);
    }

    private bool DetectWinbondFintek() {
      WinbondNuvotonFintekEnter();

      byte logicalDeviceNumber = 0;
      byte id = ReadByte(CHIP_ID_REGISTER);
      byte revision = ReadByte(CHIP_REVISION_REGISTER);
      Chip chip = Chip.Unknown;
      switch (id) {
        case 0x05:
          switch (revision) {
            case 0x07:
              chip = Chip.F71858;
              logicalDeviceNumber = F71858_HARDWARE_MONITOR_LDN;
              break;
            case 0x41:
              chip = Chip.F71882;
              logicalDeviceNumber = FINTEK_HARDWARE_MONITOR_LDN;
              break;
          } break;
        case 0x06:
          switch (revision) {
            case 0x01:
              chip = Chip.F71862;
              logicalDeviceNumber = FINTEK_HARDWARE_MONITOR_LDN;
              break;
          } break;
        case 0x07:
          switch (revision) {
            case 0x23:
              chip = Chip.F71889F;
              logicalDeviceNumber = FINTEK_HARDWARE_MONITOR_LDN;
              break;
          } break;
        case 0x08:
          switch (revision) {
            case 0x14:
              chip = Chip.F71869;
              logicalDeviceNumber = FINTEK_HARDWARE_MONITOR_LDN;
              break;
          } break;
        case 0x09:
          switch (revision) {
            case 0x01:
              chip = Chip.F71808E;
              logicalDeviceNumber = FINTEK_HARDWARE_MONITOR_LDN;
              break;
            case 0x09:
              chip = Chip.F71889ED;
              logicalDeviceNumber = FINTEK_HARDWARE_MONITOR_LDN;
              break;
          } break;
        case 0x10:
          switch (revision) {
            case 0x05:
              chip = Chip.F71889AD;
              logicalDeviceNumber = FINTEK_HARDWARE_MONITOR_LDN;
              break;
            case 0x07:
              chip = Chip.F71869A;
              logicalDeviceNumber = FINTEK_HARDWARE_MONITOR_LDN;
              break;
          } break;
        case 0x52:
          switch (revision) {
            case 0x17:
            case 0x3A:
            case 0x41:
              chip = Chip.W83627HF;
              logicalDeviceNumber = WINBOND_NUVOTON_HARDWARE_MONITOR_LDN;
              break;
          } break;
        case 0x82:
          switch (revision & 0xF0) {
            case 0x80:
              chip = Chip.W83627THF;
              logicalDeviceNumber = WINBOND_NUVOTON_HARDWARE_MONITOR_LDN;
              break;
          } break;
        case 0x85:
          switch (revision) {
            case 0x41:
              chip = Chip.W83687THF;
              logicalDeviceNumber = WINBOND_NUVOTON_HARDWARE_MONITOR_LDN;
              break;
          } break;
        case 0x88:
          switch (revision & 0xF0) {
            case 0x50:
            case 0x60:
              chip = Chip.W83627EHF;
              logicalDeviceNumber = WINBOND_NUVOTON_HARDWARE_MONITOR_LDN;
              break;
          } break;
        case 0xA0:
          switch (revision & 0xF0) {
            case 0x20:
              chip = Chip.W83627DHG;
              logicalDeviceNumber = WINBOND_NUVOTON_HARDWARE_MONITOR_LDN;
              break;
          } break;
        case 0xA5:
          switch (revision & 0xF0) {
            case 0x10:
              chip = Chip.W83667HG;
              logicalDeviceNumber = WINBOND_NUVOTON_HARDWARE_MONITOR_LDN;
              break;
          } break;
        case 0xB0:
          switch (revision & 0xF0) {
            case 0x70:
              chip = Chip.W83627DHGP;
              logicalDeviceNumber = WINBOND_NUVOTON_HARDWARE_MONITOR_LDN;
              break;
          } break;
        case 0xB3:
          switch (revision & 0xF0) {
            case 0x50:
              chip = Chip.W83667HGB;
              logicalDeviceNumber = WINBOND_NUVOTON_HARDWARE_MONITOR_LDN;
              break;
          } break;
        case 0xB4:
          switch (revision & 0xF0) {
            case 0x70:
              chip = Chip.NCT6771F;
              logicalDeviceNumber = WINBOND_NUVOTON_HARDWARE_MONITOR_LDN;
              break;
          } break;
        case 0xC3:
          switch (revision & 0xF0) {
            case 0x30:
              chip = Chip.NCT6776F;
              logicalDeviceNumber = WINBOND_NUVOTON_HARDWARE_MONITOR_LDN;
              break;
          } break;
        case 0xC5:
          switch (revision & 0xF0) {
            case 0x60:
              chip = Chip.NCT6779D;
              logicalDeviceNumber = WINBOND_NUVOTON_HARDWARE_MONITOR_LDN;
              break;
          } break;
        case 0xC8:
          switch (revision) {
            case 0x03:
              chip = Chip.NCT6791D;
              logicalDeviceNumber = WINBOND_NUVOTON_HARDWARE_MONITOR_LDN;
              break;
          } break;
      }
      if (chip == Chip.Unknown) {
        if (id != 0 && id != 0xff) {
          WinbondNuvotonFintekExit();

          ReportUnknownChip("Winbond / Nuvoton / Fintek", 
            ((id << 8) | revision));
        }
      } else {

        Select(logicalDeviceNumber);
        ushort address = ReadWord(BASE_ADDRESS_REGISTER);
        Thread.Sleep(1);
        ushort verify = ReadWord(BASE_ADDRESS_REGISTER);

        ushort vendorID = ReadWord(FINTEK_VENDOR_ID_REGISTER);

        // disable the hardware monitor i/o space lock on NCT6791D chips
        if (address == verify && chip == Chip.NCT6791D) {
          byte options = ReadByte(NUVOTON_HARDWARE_MONITOR_IO_SPACE_LOCK);

          // if the i/o space lock is enabled
          if ((options & 0x10) > 0) {

            // disable the i/o space lock
            WriteByte(NUVOTON_HARDWARE_MONITOR_IO_SPACE_LOCK,
              (byte)(options & ~0x10));
          }
        }

        WinbondNuvotonFintekExit();

        if (address != verify) {
          report.Append("Chip ID: 0x");
          report.AppendLine(chip.ToString("X"));
          report.Append("Chip revision: 0x");
          report.AppendLine(revision.ToString("X",
            CultureInfo.InvariantCulture));
          report.AppendLine("Error: Address verification failed");
          report.AppendLine();
          return false;
        }

        // some Fintek chips have address register offset 0x05 added already
        if ((address & 0x07) == 0x05)
          address &= 0xFFF8;

        if (address < 0x100 || (address & 0xF007) != 0) {
          report.Append("Chip ID: 0x");
          report.AppendLine(chip.ToString("X"));
          report.Append("Chip revision: 0x");
          report.AppendLine(revision.ToString("X",
            CultureInfo.InvariantCulture));
          report.Append("Error: Invalid address 0x");
          report.AppendLine(address.ToString("X",
            CultureInfo.InvariantCulture));
          report.AppendLine();
          return false;
        }

        switch (chip) {
          case Chip.W83627DHG:
          case Chip.W83627DHGP:
          case Chip.W83627EHF:
          case Chip.W83627HF:
          case Chip.W83627THF:
          case Chip.W83667HG:
          case Chip.W83667HGB:
          case Chip.W83687THF:
            superIOs.Add(new W836XX(chip, revision, address));
            break;
          case Chip.NCT6771F:
          case Chip.NCT6776F:
          case Chip.NCT6779D:
          case Chip.NCT6791D:
            superIOs.Add(new NCT677X(chip, revision, address));
            break;
          case Chip.F71858:
          case Chip.F71862:
          case Chip.F71869:
          case Chip.F71869A:
          case Chip.F71882:
          case Chip.F71889AD:
          case Chip.F71889ED:
          case Chip.F71889F:
          case Chip.F71808E:
            if (vendorID != FINTEK_VENDOR_ID) {
              report.Append("Chip ID: 0x");
              report.AppendLine(chip.ToString("X"));
              report.Append("Chip revision: 0x");
              report.AppendLine(revision.ToString("X",
                CultureInfo.InvariantCulture));
              report.Append("Error: Invalid vendor ID 0x");
              report.AppendLine(vendorID.ToString("X",
                CultureInfo.InvariantCulture));
              report.AppendLine();
              return false;
            }
            superIOs.Add(new F718XX(chip, address));
            break;
          default: break;
        }

        return true;
      }

      return false;
    }

    #endregion

    #region ITE

    private const byte IT87_ENVIRONMENT_CONTROLLER_LDN = 0x04;
    private const byte IT8705_GPIO_LDN = 0x05;
    private const byte IT87XX_GPIO_LDN = 0x07;
    private const byte IT87_CHIP_VERSION_REGISTER = 0x22;

    private void IT87Enter() {
      Ring0.WriteIoPort(registerPort, 0x87);
      Ring0.WriteIoPort(registerPort, 0x01);
      Ring0.WriteIoPort(registerPort, 0x55);
      Ring0.WriteIoPort(registerPort, 0x55);
    }

    private void IT87Exit() {
      Ring0.WriteIoPort(registerPort, CONFIGURATION_CONTROL_REGISTER);
      Ring0.WriteIoPort(valuePort, 0x02);
    }

    private bool DetectIT87() {

      // IT87XX can enter only on port 0x2E
      if (registerPort != 0x2E)
        return false;

      IT87Enter();

      ushort chipID = ReadWord(CHIP_ID_REGISTER);
      Chip chip;
      switch (chipID) {
        case 0x8705: chip = Chip.IT8705F; break;
        case 0x8712: chip = Chip.IT8712F; break;
        case 0x8716: chip = Chip.IT8716F; break;
        case 0x8718: chip = Chip.IT8718F; break;
        case 0x8720: chip = Chip.IT8720F; break;
        case 0x8721: chip = Chip.IT8721F; break;
        case 0x8726: chip = Chip.IT8726F; break;
        case 0x8728: chip = Chip.IT8728F; break;
        case 0x8771: chip = Chip.IT8771E; break;
        case 0x8772: chip = Chip.IT8772E; break;
        default: chip = Chip.Unknown; break;
      }
      if (chip == Chip.Unknown) {
        if (chipID != 0 && chipID != 0xffff) {
          IT87Exit();

          ReportUnknownChip("ITE", chipID);
        }
      } else {
        Select(IT87_ENVIRONMENT_CONTROLLER_LDN);
        ushort address = ReadWord(BASE_ADDRESS_REGISTER);
        Thread.Sleep(1);
        ushort verify = ReadWord(BASE_ADDRESS_REGISTER);

        byte version = (byte)(ReadByte(IT87_CHIP_VERSION_REGISTER) & 0x0F);

        ushort gpioAddress;
        ushort gpioVerify;
        if (chip == Chip.IT8705F) {
          Select(IT8705_GPIO_LDN);
          gpioAddress = ReadWord(BASE_ADDRESS_REGISTER);
          Thread.Sleep(1);
          gpioVerify = ReadWord(BASE_ADDRESS_REGISTER);
        } else {
          Select(IT87XX_GPIO_LDN);
          gpioAddress = ReadWord(BASE_ADDRESS_REGISTER + 2);
          Thread.Sleep(1);
          gpioVerify = ReadWord(BASE_ADDRESS_REGISTER + 2);
        }
        
        IT87Exit();

        if (address != verify || address < 0x100 || (address & 0xF007) != 0) {
          report.Append("Chip ID: 0x");
          report.AppendLine(chip.ToString("X"));
          report.Append("Error: Invalid address 0x");
          report.AppendLine(address.ToString("X",
            CultureInfo.InvariantCulture));
          report.AppendLine();
          return false;
        }

        if (gpioAddress != gpioVerify || gpioAddress < 0x100 ||
          (gpioAddress & 0xF007) != 0) {
          report.Append("Chip ID: 0x");
          report.AppendLine(chip.ToString("X"));
          report.Append("Error: Invalid GPIO address 0x");
          report.AppendLine(gpioAddress.ToString("X",
            CultureInfo.InvariantCulture));
          report.AppendLine();
          return false;
        }

        superIOs.Add(new IT87XX(chip, address, gpioAddress, version));
        return true;
      }

      return false;
    }

    #endregion

    #region SMSC

    private void SMSCEnter() {
      Ring0.WriteIoPort(registerPort, 0x55);
    }

    private void SMSCExit() {
      Ring0.WriteIoPort(registerPort, 0xAA);
    }

    private bool DetectSMSC() {
      SMSCEnter();

      ushort chipID = ReadWord(CHIP_ID_REGISTER);
      Chip chip;
      switch (chipID) {
        default: chip = Chip.Unknown; break;
      }
      if (chip == Chip.Unknown) {
        if (chipID != 0 && chipID != 0xffff) {
          SMSCExit();

          ReportUnknownChip("SMSC", chipID);
        }
      } else {
        SMSCExit();
        return true;
      }

      return false;
    }

    #endregion

    private void Detect() {

      for (int i = 0; i < REGISTER_PORTS.Length; i++) {
        registerPort = REGISTER_PORTS[i];
        valuePort = VALUE_PORTS[i];

        if (DetectWinbondFintek()) continue;

        if (DetectIT87()) continue;

        if (DetectSMSC()) continue;
      }
    }

    public LPCIO() {
      if (!Ring0.IsOpen)
        return;

      if (!Ring0.WaitIsaBusMutex(100))
        return;

      Detect();

      Ring0.ReleaseIsaBusMutex();
    }

    public ISuperIO[] SuperIO {
      get {
        return superIOs.ToArray();
      }
    }

    public string GetReport() {
      if (report.Length > 0) {
        return "LPCIO" + Environment.NewLine + Environment.NewLine + report;
      } else
        return null;
    }
  }
}