const (
    ShiftMask   = 1 << 0
    LockMask    = 1 << 1
    ControlMask = 1 << 2
    Mod1Mask    = 1 << 3
    Mod2Mask    = 1 << 4
    Mod3Mask    = 1 << 5
    Mod4Mask    = 1 << 6
    Mod5Mask    = 1 << 7
    Button1Mask = 1 << 8
    Button2Mask = 1 << 9
    Button3Mask = 1 << 10
    Button4Mask = 1 << 11
    Button5Mask = 1 << 12
)

var ASCIIKeycodes = [0x80]key.Code{
    'a': key.CodeA,
    'b': key.CodeB,
    'c': key.CodeC,
    'd': key.CodeD,
    'e': key.CodeE,
    'f': key.CodeF,
    'g': key.CodeG,
    'h': key.CodeH,
    'i': key.CodeI,
    'j': key.CodeJ,
    'k': key.CodeK,
    'l': key.CodeL,
    'm': key.CodeM,
    'n': key.CodeN,
    'o': key.CodeO,
    'p': key.CodeP,
    'q': key.CodeQ,
    'r': key.CodeR,
    's': key.CodeS,
    't': key.CodeT,
    'u': key.CodeU,
    'v': key.CodeV,
    'w': key.CodeW,
    'x': key.CodeX,
    'y': key.CodeY,
    'z': key.CodeZ,

    '1': key.Code1,
    '2': key.Code2,
    '3': key.Code3,
    '4': key.Code4,
    '5': key.Code5,
    '6': key.Code6,
    '7': key.Code7,
    '8': key.Code8,
    '9': key.Code9,
    '0': key.Code0,

    ' ':  key.CodeSpacebar,
    '-':  key.CodeHyphenMinus,
    '=':  key.CodeEqualSign,
    '[':  key.CodeLeftSquareBracket,
    ']':  key.CodeRightSquareBracket,
    '\\': key.CodeBackslash,
    ';':  key.CodeSemicolon,
    '\'': key.CodeApostrophe,
    '`':  key.CodeGraveAccent,
    ',':  key.CodeComma,
    '.':  key.CodeFullStop,
    '/':  key.CodeSlash,
}

var NonUnicodeKeycodes = map[rune]key.Code{
    xkISOLeftTab: key.CodeTab,
    xkBackSpace:  key.CodeDeleteBackspace,
    xkTab:        key.CodeTab,
    xkReturn:     key.CodeReturnEnter,
    xkEscape:     key.CodeEscape,
    xkHome:       key.CodeHome,
    xkLeft:       key.CodeLeftArrow,
    xkUp:         key.CodeUpArrow,
    xkRight:      key.CodeRightArrow,
    xkDown:       key.CodeDownArrow,
    xkPageUp:     key.CodePageUp,
    xkPageDown:   key.CodePageDown,
    xkEnd:        key.CodeEnd,
    xkInsert:     key.CodeInsert,
    xkMenu:       key.CodeRightGUI,

    xkF1:  key.CodeF1,
    xkF2:  key.CodeF2,
    xkF3:  key.CodeF3,
    xkF4:  key.CodeF4,
    xkF5:  key.CodeF5,
    xkF6:  key.CodeF6,
    xkF7:  key.CodeF7,
    xkF8:  key.CodeF8,
    xkF9:  key.CodeF9,
    xkF10: key.CodeF10,
    xkF11: key.CodeF11,
    xkF12: key.CodeF12,

    xkShiftL:   key.CodeLeftShift,
    xkShiftR:   key.CodeRightShift,
    xkControlL: key.CodeLeftControl,
    xkControlR: key.CodeRightControl,
    xkAltL:     key.CodeLeftAlt,
    xkAltR:     key.CodeRightAlt,
    xkSuperL:   key.CodeLeftGUI,
    xkSuperR:   key.CodeRightGUI,

    xkDelete: key.CodeDeleteForward,

    xf86xkAudioRaiseVolume: key.CodeVolumeUp,
    xf86xkAudioLowerVolume: key.CodeVolumeDown,
    xf86xkAudioMute:        key.CodeMute,
}