/** DGui project file.

Copyright: Trogu Antonio Davide 2011-2013

License: $(HTTP boost.org/LICENSE_1_0.txt, Boost License 1.0).

Authors: Trogu Antonio Davide
*/
module dguihub.registry;

pragma(lib, "advapi32.lib");

private import std.utf : toUTFz, toUTF8;

private import std..string : format;

private import std.conv;
import dguihub.core.winapi;
import dguihub.core.interfaces.idisposable;
import dguihub.core.exception;
import dguihub.core.handle;

enum RegistryValueType : uint {
   binary = REG_BINARY,
   dword = REG_DWORD,
   qword = REG_QWORD,
   string_ = REG_SZ,
}

interface IRegistryValue {
   public void write(RegistryKey owner, string name);
   public RegistryValueType valueType();
}

abstract class RegistryValue(T) : IRegistryValue {
   private T _value;

   public this(T val) {
      this._value = val;
   }

   @property public abstract RegistryValueType valueType();
}

final class RegistryValueBinary : RegistryValue!(ubyte[]) {
   public this(ubyte[] b) {
      super(b);
   }

   @property public override RegistryValueType valueType() {
      return RegistryValueType.binary;
   }

   public override string toString() {
      string s;

      foreach (ubyte b; this._value) {
         s ~= format("%02X", b);
      }

      return s;
   }

   public void write(RegistryKey owner, string name) {
      ulong res = RegSetValueExW(owner.handle, toUTFz!(wchar*)(name), 0,
            REG_BINARY, cast(ubyte*)this._value.ptr, this._value.length);

      if (res != ERROR_SUCCESS) {
         throwException!(RegistryException)("RegSetValueEx failed, Key '%s'", name);
      }
   }
}

final class RegistryValueString : RegistryValue!(string) {
   public this(string s) {
      super(s);
   }

   @property public override RegistryValueType valueType() {
      return RegistryValueType.string_;
   }

   public override string toString() {
      return this._value.idup;
   }

   public void write(RegistryKey owner, string name) {
      ulong res = RegSetValueExW(owner.handle, toUTFz!(wchar*)(name), 0,
            REG_SZ, cast(ubyte*)this._value.ptr, this._value.length);

      if (res != ERROR_SUCCESS) {
         throwException!(RegistryException)("RegSetValueEx failed, Key '%s'", name);
      }
   }
}

final class RegistryValueDword : RegistryValue!(uint) {
   public this(uint i) {
      super(i);
   }

   @property public override RegistryValueType valueType() {
      return RegistryValueType.dword;
   }

   public override string toString() {
      return to!(string)(this._value);
   }

   public void write(RegistryKey owner, string name) {
      ulong res = RegSetValueExW(owner.handle, toUTFz!(wchar*)(name), 0,
            REG_DWORD, cast(ubyte*)&this._value, uint.sizeof);

      if (res != ERROR_SUCCESS) {
         throwException!(RegistryException)("RegSetValueEx failed, Key '%s'", name);
      }
   }
}

final class RegistryValueQword : RegistryValue!(ulong) {
   public this(ulong l) {
      super(l);
   }

   @property public override RegistryValueType valueType() {
      return RegistryValueType.qword;
   }

   public override string toString() {
      return to!(string)(this._value);
   }

   public void write(RegistryKey owner, string name) {
      ulong res = RegSetValueExW(owner.handle, toUTFz!(wchar*)(name), 0,
            REG_QWORD, cast(ubyte*)&this._value, ulong.sizeof);

      if (res != ERROR_SUCCESS) {
         throwException!(RegistryException)("RegSetValueEx failed, Key '%s'", name);
      }
   }
}

final class RegistryKey : Handle!(HKEY), IDisposable {
   private bool _owned;

   package this(HKEY hKey, bool owned = true) {
      this._handle = hKey;
      this._owned = owned;
   }

   public ~this() {
      this.dispose();
   }

   public void dispose() {
      if (this._owned) {
         RegCloseKey(this._handle);
         this._handle = null;
      }
   }

   private void doDeleteSubKey(HKEY hKey, string name) {
      const uint MAX_KEY_LENGTH = 0xFF;
      const uint MAX_VALUE_NAME = 0x3FFF;

      HKEY hDelKey;
      uint valuesCount, subKeysCount;
      wchar[] keyName = new wchar[MAX_KEY_LENGTH];
      wchar[] valName = new wchar[MAX_VALUE_NAME];

      if (RegOpenKeyExW(hKey, toUTFz!(wchar*)(name), 0, KEY_ALL_ACCESS,
            &hDelKey) != ERROR_SUCCESS) {
         throwException!(RegistryException)("Cannot open Key '%s'", to!(string)(name.ptr));
      }

      if (RegQueryInfoKeyW(hDelKey, null, null, null, &subKeysCount, null,
            null, &valuesCount, null, null, null, null) != ERROR_SUCCESS) {
         throwException!(RegistryException)("Cannot query Key '%s'", to!(string)(name.ptr));
      }

      for (int i = 0; i < subKeysCount; i++) {
         uint size = MAX_KEY_LENGTH;

         RegEnumKeyExW(hDelKey, 0, keyName.ptr, &size, null, null, null, null);
      }
      this.doDeleteSubKey(hDelKey, toUTF8(keyName));

      for (int i = 0; i < valuesCount; i++) {
         uint size = MAX_VALUE_NAME;

         if (RegEnumValueW(hDelKey, 0, valName.ptr, &size, null, null, null, null) != ERROR_SUCCESS) {
            throwException!(RegistryException)("Cannot enumerate values from key '%s'", name);
         }

         if (RegDeleteValueW(hDelKey, valName.ptr) != ERROR_SUCCESS) {
            throwException!(RegistryException)("Cannot delete Value '%s'", toUTF8(valName));
         }
      }

      RegCloseKey(hDelKey);

      if (RegDeleteKeyW(hKey, toUTFz!(wchar*)(name)) != ERROR_SUCCESS) {
         throwException!(RegistryException)("Cannot delete Key '%s'", to!(string)(name.ptr));
      }
   }

   public RegistryKey createSubKey(string name) {
      HKEY hKey;
      uint disp;

      int res = RegCreateKeyExW(this._handle, toUTFz!(wchar*)(name), 0, null,
            0, KEY_ALL_ACCESS, null, &hKey, &disp);

      switch (res) {
      case ERROR_SUCCESS:
         return new RegistryKey(hKey);

      default:
         throwException!(RegistryException)("Cannot create Key '%s'", name);
      }

      return null;
   }

   public void deleteSubKey(string name) {
      this.doDeleteSubKey(this._handle, name);
   }

   public RegistryKey getSubKey(string name) {
      HKEY hKey;

      int res = RegOpenKeyExW(this._handle, toUTFz!(wchar*)(name), 0, KEY_ALL_ACCESS, &hKey);

      switch (res) {
      case ERROR_SUCCESS:
         return new RegistryKey(hKey);

      default:
         throwException!(RegistryException)("Cannot retrieve Key '%s'", name);
      }

      return null;
   }

   public void setValue(string name, IRegistryValue val) {
      val.write(this, name);
   }

   public IRegistryValue getValue(string name) {
      uint len;
      uint type;
      IRegistryValue ival = null;

      int res = RegQueryValueExW(this._handle, toUTFz!(wchar*)(name), null, &type, null, &len);

      if (res != ERROR_SUCCESS) {
         return null;
      }

      switch (type) {
      case REG_BINARY:
         ubyte[] val = new ubyte[len];
         RegQueryValueExW(this._handle, toUTFz!(wchar*)(name), null, &type, val.ptr, &len);
         ival = new RegistryValueBinary(val);
         break;

      case REG_DWORD:
         uint val;
         RegQueryValueExW(this._handle, toUTFz!(wchar*)(name), null, &type,
               cast(ubyte*)&val, &len);
         ival = new RegistryValueDword(val);
         break;

      case REG_QWORD:
         ulong val;
         RegQueryValueExW(this._handle, toUTFz!(wchar*)(name), null, &type,
               cast(ubyte*)&val, &len);
         ival = new RegistryValueQword(val);
         break;

      case REG_SZ:
         wchar[] val = new wchar[len];
         RegQueryValueExW(this._handle, toUTFz!(wchar*)(name), null, &type,
               cast(ubyte*)val.ptr, &len);
         ival = new RegistryValueString(toUTF8(val));
         break;

      default:
         throwException!(RegistryException)("Unsupported Format");
      }

      return ival;
   }
}

final class Registry {
   private static RegistryKey _classesRoot;
   private static RegistryKey _currentConfig;
   private static RegistryKey _currentUser;
   private static RegistryKey _dynData;
   private static RegistryKey _localMachine;
   private static RegistryKey _performanceData;
   private static RegistryKey _users;

   private this() {

   }

   @property public static RegistryKey classesRoot() {
      if (!_classesRoot) {
         _classesRoot = new RegistryKey(HKEY_CLASSES_ROOT, false);
      }

      return _classesRoot;
   }

   @property public static RegistryKey currentConfig() {
      if (!_currentConfig) {
         _currentConfig = new RegistryKey(HKEY_CURRENT_CONFIG, false);
      }

      return _currentConfig;
   }

   @property public static RegistryKey currentUser() {
      if (!_currentUser) {
         _currentUser = new RegistryKey(HKEY_CURRENT_USER, false);
      }

      return _currentUser;
   }

   @property public static RegistryKey dynData() {
      if (!_dynData) {
         _dynData = new RegistryKey(HKEY_DYN_DATA, false);
      }

      return _dynData;
   }

   @property public static RegistryKey localMachine() {
      if (!_localMachine) {
         _localMachine = new RegistryKey(HKEY_LOCAL_MACHINE, false);
      }

      return _localMachine;
   }

   @property public static RegistryKey performanceData() {
      if (!_performanceData) {
         _performanceData = new RegistryKey(HKEY_PERFORMANCE_DATA, false);
      }

      return _performanceData;
   }

   @property public static RegistryKey users() {
      if (!_users) {
         _users = new RegistryKey(HKEY_USERS, false);
      }

      return _users;
   }
}