#NoEnv
#SingleInstance Force
#Persistent

; Retrieve user-set resolutions or fall back on defaults

RegRead, ResolutionsString, HKEY_CURRENT_USER\Software\JohnAJ\DRM, Resolutions

if (ErrorLevel = 1)
{
  ResolutionsString = 1600x1200|1024x768|800x600|640x480 ; 4:3
  if (A_ScreenWidth/A_ScreenHeight = 1.6)
    ResolutionsString = 1920x1200|1680x1050|1440x900|1280x800 ; 16:10
  if (Round(A_ScreenWidth/A_ScreenHeight, 2) = 1.77)
    ResolutionsString = 1920x1080|1366x768|1280x720|854x480 ; 16:9
  RegWrite, REG_SZ, HKEY_CURRENT_USER\Software\JohnAJ\DRM, Resolutions, %ResolutionsString%
}

Resolutions := StrSplit(ResolutionsString, "|")

; Retrieve user-set exceptions

RegRead, IgnoreString, HKEY_CURRENT_USER\Software\JohnAJ\DRM, Ignore
IgnoreString := "|" IgnoreString ; leading pipe for easy string matching

if (ErrorLevel = 1)
{
  IgnoreString = ""
  RegWrite, REG_SZ, HKEY_CURRENT_USER\Software\JohnAJ\DRM, Ignore, % ""
}

RegRead, IgnoreSizeString, HKEY_CURRENT_USER\Software\JohnAJ\DRM, IgnoreSize
IgnoreSizeString := "|" IgnoreSizeString ; leading pipe for easy string matching

if (ErrorLevel = 1)
{
  IgnoreSizeString = ""
  RegWrite, REG_SZ, HKEY_CURRENT_USER\Software\JohnAJ\DRM, IgnoreSize, % ""
}

; Set up tray menu

Menu, Tray, NoStandard
Menu, Tray, Icon, shell32.dll, 95
Menu, Tray, Tip, Dynamic Resolution Manager
for k, res in Resolutions
  if (res = "")
    Menu, Tray, Add
  else
    Menu, Tray, Add, %res%, ButtonResolution
Menu, Tray, Add
Menu, Tray, Add, &Configure..., ButtonConfigure
Menu, Tray, Add, &Restart, ButtonRestart
Menu, Tray, Add, E&xit, ButtonExit
AddCheckmark()
OnMessage(0x404, "NotifyIcon")
return

ButtonExit:
ExitApp

ButtonRestart:
Reload
return

; Custom hotkeys

; Open configuration

ButtonConfigure()
{
  RegWrite, REG_SZ, HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Applets\Regedit, LastKey, HKEY_CURRENT_USER\Software\JohnAJ\DRM
  Run, %A_WinDir%\regedit.exe /m
}

; Select resolution from tray menu

ButtonResolution(ItemName, ItemPos, MenuName)
{
  w := 0
  h := 0
  r := 0
  for k, v in StrSplit(ItemName, " ")
  {
    if (k = 1)
    {
      a := StrSplit(v, "x")
      w := a[1]
      h := a[2]
    }
    else if ("Hz" = SubStr(v, StrLen(v) - 1))
      r := SubStr(v, 1, StrLen(v) - 2)
  }
  if (w = 0 or h = 0)
    MsgBox, Invalid width or height
  new := {width: w, height: h, rate: r, depth: 32}
  old := Get()
  SwitchResolution(new, old)
}

; Add checkmark to current resolution (if available)

AddCheckmark(res := 0)
{
  if (res = 0)
    res := Get()
  Menu, Tray, UseErrorLevel
  Menu, Tray, Check, % res.width "x" res.height " " res.rate "Hz"
  if (ErrorLevel = 1)
    Menu, Tray, Check, % res.width "x" res.height
  Menu, Tray, UseErrorLevel, Off
}

RemoveCheckmark(res := 0)
{
  if (res = 0)
    res := Get()
  Menu, Tray, UseErrorLevel
  Menu, Tray, Uncheck, % res.width "x" res.height " " res.rate "Hz"
  if (ErrorLevel = 1)
    Menu, Tray, Uncheck, % res.width "x" res.height
  Menu, Tray, UseErrorLevel, Off
}

; Save window positions, switch to given resolution, restore window positions

SwitchResolution(new, old)
{
  Positions := {}
  
  Save(Positions)
  Set(new)
  Sleep, 500
  Restore(Positions)
  RemoveCheckmark(old)
  AddCheckmark(new)
  
  TrayTip, Resolution changed, % "Press Escape within 3 seconds to revert."
  KeyWait, Esc, D T3
  TrayTip
  if (ErrorLevel = 1) ; user didn't press escape
    return
  
  Set(old)
  Sleep, 500
  Restore(Positions)
  RemoveCheckmark(new)
  AddCheckmark(old)
}

Save(ByRef Positions)
{
  global IgnoreString
  global IgnoreSizeString
  
  Positions := {}
  WinGet, id, list
  SysGet, WorkArea, MonitorWorkArea
  wa := { w: WorkAreaRight - WorkAreaLeft, h: WorkAreaBottom - WorkAreaTop }
  
  Loop, %id%
  {
    i := id%A_Index%
    p := {}
    DoIgnore := DoIgnoreSize := false
    
    WinReallyGetPos(i, x, y, w, h)
    WinGet, exe, ProcessName, ahk_id %i%
    WinGet, style, Style, ahk_id %i%
    SysGet, bx, 32 ; window border thickness (x)
    SysGet, by, 33 ; window border thickness (y)
    cw := w - bx * 2 ; client width
    ch := h - by * 2 ; client height
    
    ; Ignore size for windows that cannot be resized
    
    if (style & 0x40000 = 0) ; WS_SIZEBOX
      DoIgnoreSize := true
    
    ; Custom rules
    
    ; Example:
    ; if (exe = "mpc-hc.exe" and cw = 294)
    ;   DoIgnoreSize := true
    
    ; Ignore position and size (2)
    
    if (DoIgnore or InStr(IgnoreString, "|" exe))
      p := {x: x, y: y, w: w, h: h, ignore: 2, align: 0}
    
    ; Ignore size, but retain position (1)
    
    else if (DoIgnoreSize or InStr(IgnoreSizeString, "|" exe))
    {
      p.ignore := 1
      p.w := w
      p.h := h
      p.x := x / wa.w
      p.y := y / wa.h
      
      ; Re-calculate position relative to right/bottom if necessary
      
      p.align := 1 ; to align right, this should be divisible by 3; bottom, by 5
      if (x > wa.w - (x + w))
      {
        p.align := p.align * 3
        p.x := (wa.w - (x + w)) / wa.w
      }
      if (y > wa.h - (y + h))
      {
        p.align := p.align * 5
        p.y := (wa.h - (y + h)) / wa.h
      }
    }
    
    ; Retain position and size (0)
    
    else
      p := {x: x / wa.w, y: y / wa.h, w: w / wa.w, h: h / wa.h, ignore: 0, align: 0}
    
    Positions[i] := p
  }
}

Restore(Positions)
{
  SysGet, WorkArea, MonitorWorkArea
  wa := { w: WorkAreaRight - WorkAreaLeft, h: WorkAreaBottom - WorkAreaTop }
  for i, p in Positions
  {
    if (p.ignore = 2) ; ignore position and size
      WinReallyMove(i, p.x, p.y, p.w, p.h)
    else if (p.ignore = 1) ; ignore size, but retain position
    {
      x := p.x * wa.w
      y := p.y * wa.h
      if (Mod(p.align, 3) = 0) ; align right
        x := wa.w - x - p.w
      if (Mod(p.align, 5) = 0) ; align bottom
        y := wa.h - y - p.h
      WinReallyMove(i, x, y, p.w, p.h)
    }
    else ; retain position and size
      WinReallyMove(i, p.x * wa.w, p.y * wa.h, p.w * wa.w, p.h * wa.h)
  }
}

; Set screen resolution

Set(res)
{
  VarSetCapacity(DeviceMode, 156, 0)
  NumPut(156, DeviceMode, 36)
  DllCall("EnumDisplaySettingsA", UInt, 0, UInt, -1, UInt, &DeviceMode)
  NumPut(0x5c0000, DeviceMode, 40)
  NumPut(res.depth, DeviceMode, 104)
  NumPut(res.width, DeviceMode, 108)
  NumPut(res.height, DeviceMode, 112)
  if (res.rate > 0)
    NumPut(res.rate, DeviceMode, 120)
  DllCall("ChangeDisplaySettingsA", UInt, &DeviceMode, UInt, 0)
}

; Get screen resolution

Get()
{
  VarSetCapacity(DeviceMode, 156, 0)
  NumPut(156, DeviceMode, 36)
  DllCall("EnumDisplaySettingsA", UInt, 0, UInt, -1, UInt, &DeviceMode)
  w := NumGet(&DeviceMode, 108, "uint4")
  h := NumGet(&DeviceMode, 112, "uint4")
  d := NumGet(&DeviceMode, 104, "uint4")
  r := NumGet(&DeviceMode, 120, "uint4")
  return {width: w, height: h, depth: d, rate: r}
}

; Get position of any window, even a minimized one

WinReallyGetPos(hwnd, ByRef x, ByRef y, ByRef w="", ByRef h="")
{
    VarSetCapacity(wp, 44), NumPut(44, wp)
    DllCall("GetWindowPlacement", "uint", hwnd, "uint", &wp)
    x := NumGet(wp, 28, "int")
    y := NumGet(wp, 32, "int")
    w := NumGet(wp, 36, "int") - x
    h := NumGet(wp, 40, "int") - y
}

; Set position of any window, even a minimized one

WinReallyMove(hwnd, x, y, w, h)
{
    VarSetCapacity(wp, 44, 0), NumPut(44, wp, "uint")
    NumPut(5, wp, 8, "uint")
    NumPut(x, wp, 28, "int")
    NumPut(y, wp, 32, "int")
    NumPut(w + x, wp, 36, "int")
    NumPut(h + y, wp, 40, "int")
    DllCall("SetWindowPlacement", "ptr", hwnd, "ptr", &wp)
}