#!/usr/bin/python2


# Python
import sys
import os
import subprocess
import time


def getOutputs():
    """
    For the first screen, get the names of the outputs and whether they're currently connected.

    Returns:
     (list)
     Each element is:
      (tuple)
      Tuple has elements:
       0:
        (str)
        Name of output
       1:
        (bool)
        Whether the output is currently connected.
    """
    # Run xrandr
    popen = subprocess.Popen(["xrandr", "--screen", "0", "--query"], stdout=subprocess.PIPE)
    popen.wait()
    (out, err) = popen.communicate()

    # Parse output
    lines = out.split("\n")
    if lines[0][:9] != "Screen 0:":
        raise RuntimeError("Unexpected preamble from xrandr --query")

    outputs = []
    for line in lines[1:]:
        print line
        if len(line) > 0 and line[1] != " ":
            lineFields = line.split(" ")
            outputs.append((lineFields[0], lineFields[1] == "connected"))

    return outputs

def generateTimings(i_timingCommand, i_width, i_height, i_fieldRate, i_interlaced=False):
    """
    Params:
     i_timingCommand:
      (str)
     i_width, i_height:
      Either (int)
      or (str)
       String representations of an integer.
     i_fieldRate:
      (str)
      String representations of a float.
     i_interlaced:
      (bool)
      True: Make an interlaced mode

    Returns:
     (list)
     eg. ['Modeline', '1920x1080i60.00', '86.5', '1920', '2048', '2248', '2576', '1080', '1083', '1088', '1120', '+hsync', '+vsync', 'Interlace']
    """
    # Run cvt or gtf
    popen = subprocess.Popen([i_timingCommand, str(i_width), str(i_height), i_fieldRate], stdout=subprocess.PIPE)
    popen.wait()
    (out, err) = popen.communicate()

    # Parse output
    lines = out.split("\n")
    modespec = None
    for line in lines:
        line = line.strip()
        if line.startswith("Modeline "):
            parts = line.split(" ")
            modespec = [p  for p in parts  if p != ""]
            break

    # Remove enclosing quotes in mode name
    modespec[1] = modespec[1].replace('"', '')

    # Modify mode name (which was generated by cvt/gtf)
    # to show whether progressive or interlaced,
    # and add actual interlacing options if desired
    if not i_interlaced:
        modespec[1] = modespec[1].replace('_', 'p')
    else:
        modespec[1] = modespec[1].replace('_', 'i')

        modespec.append("Interlace")
        modespec[2] = str(float(modespec[2]) / 2.0)

    #
    return modespec

def recreateMode(i_outputName, i_modespec, i_printXrandrCommands = False):
    """
    Params:
     i_outputName:
      (str)
     i_modespec:
      (list)
     i_printXrandrCommands:
      (bool)
    """
    #print "i_modespec: " + str(i_modespec)
    xrandrCommand = ["xrandr", "--delmode", i_outputName]
    xrandrCommand += [i_modespec[1]]
    if i_printXrandrCommands:
        print(subprocess.list2cmdline(xrandrCommand))
    subprocess.Popen(xrandrCommand)

    time.sleep(0.25)

    xrandrCommand = ["xrandr", "--rmmode"]
    xrandrCommand += [i_modespec[1]]
    if i_printXrandrCommands:
        print(subprocess.list2cmdline(xrandrCommand))
    subprocess.Popen(xrandrCommand)

    time.sleep(0.25)

    xrandrCommand = ["xrandr", "--newmode"]
    xrandrCommand += i_modespec[1:]
    if i_printXrandrCommands:
        print(subprocess.list2cmdline(xrandrCommand))
    subprocess.Popen(xrandrCommand)

    time.sleep(0.25)

    xrandrCommand = ["xrandr", "--addmode", i_outputName]
    xrandrCommand += [i_modespec[1]]
    if i_printXrandrCommands:
        print(subprocess.list2cmdline(xrandrCommand))
    subprocess.Popen(xrandrCommand)

def setMode(i_outputName, i_modespec, i_printXrandrCommands = False):
    """
    Params:
     i_outputName:
      (str)
     i_modespec:
      (list)
     i_printXrandrCommands:
      (bool)
    """
    xrandrCommand = ["xrandr", "--output", i_outputName]
    xrandrCommand += ["--mode", i_modespec[1]]
    if i_printXrandrCommands:
        print(subprocess.list2cmdline(xrandrCommand))
    subprocess.Popen(xrandrCommand)


if __name__ == "__main__":

    # + Parse command line {{{

    COMMAND_NAME = "easy_xrandr"

    def printUsage(i_outputStream):
        i_outputStream.write('''\
''' + COMMAND_NAME + ''' by Daniel Lopez, 04/12/2016
xrandr wrapper

Usage:
======
''' + COMMAND_NAME + ''' <action> <width> <height> <field rate> [options...]

Params:
 action:
  Either 'add'
   Just add the new mode to xrandr's list
  or 'set'
   Add the new mode and also switch to it now.
 width, height:
  Desired resolution width and height in integer pixels
  eg. 1024 and 768
 field rate:
  Desired field rate in floating point Hz
  eg. 60.1
  In non-interlaced modes, this is the same as the frame rate,
  and in interlaced modes, this is double the actual full frame rate.

Options:
 Output selection
  --output <name>
   Choose which output to control

 Interlace
  --interlace
   Create an interlaced mode.
   In this case the actual full frame rate will turn out to be half of
   the number given for the <field rate> parameter.

 Generating timings
  --cvt
   Use the 'cvt' command to generate the timings
   (This is the default).
  --gtf
   Use the 'gtf' command to generate the timings.
''')

    #
    param_action = None  # "add" or "set"
    param_width = None
    param_height = None
    param_fieldRate = None
    interlaced = False
    timingCommand = "cvt"
    outputName = "DVI-I-1"

    import sys
    argNo = 1
    while argNo < len(sys.argv):
        arg = sys.argv[argNo]
        argNo += 1

        if arg[0] == "-":

            if arg == "--help":
                printUsage(sys.stdout)
                sys.exit(0)

            if arg == "--cvt":
                timingCommand = "cvt"
            elif arg == "--gtf":
                timingCommand = "gtf"
            elif arg == "--interlace":
                interlaced = True
            elif arg == "--output":
                if argNo >= len(sys.argv):
                    print("--output requires an argument")
                    sys.exit(-1)

                arg = sys.argv[argNo]
                argNo += 1

                outputName = arg
            else:
                print("Unrecognised option: " + arg)
                sys.exit(-1)

        else:
            # Collect command-line arguments
            if param_action == None:
                param_action = arg
            elif param_width == None:
                param_width = arg
            elif param_height == None:
                param_height = arg
            elif param_fieldRate == None:
                param_fieldRate = arg
            else:
                print("Too many arguments.")
                sys.exit(-1)

    if param_fieldRate == None:
        print("Insufficient arguments.")
        sys.exit(-1)

    # + }}}

    # + Generate timings {{{

    print("Generating timings with " + timingCommand)
    modespec = generateTimings(timingCommand, param_width, param_height, param_fieldRate, interlaced)
    #print modespec
    if modespec == None:
        print("Failed to parse timings.")
        sys.exit(1)

    ##
    #modespec = modespec[:-2]
    #modespec.append("-hsync")
    #modespec.append("-vsync")

    #
    print modespec
    #sys.exit(0)

    # + }}}

    recreateMode(outputName, modespec, True)

    if param_action == "set":
        time.sleep(0.25)
        setMode(outputName, modespec)