"""
This subfile to Grail handles window settings and calculations.
-> Only works on MS Windows!
"""

__author__ = "Lukas Mahler"
__copyright__ = "Copyright 2018-2021"
__version__ = "1.0.0"
__date__ = "25.11.2020"
__email__ = "lm@ankerlab.de"
__status__ = "Development"


import win32api
import win32gui


def getCursorPos():
    flags, hcursor, (x, y) = win32gui.GetCursorInfo()
    return {"x": x, "y": y}


def getMonitors():
    monitors = []
    for hMonitor, hdcMonitor, pyRect in win32api.EnumDisplayMonitors():
        monitors.append(pyRect)
    #print(monitors)
    return monitors


def getResolution(monitors):
    resolutions = {}
    index = 0
    for monitor in monitors:
        x_from	= monitor[0]
        x_to	= monitor[2]
        y_from	= monitor[1]
        y_to	= monitor[3]
        res_x = x_to - x_from
        res_y = y_to - y_from
        res = (res_x, res_y)
        resolutions['Monitor'+str(index)] = res
        index += 1

    return resolutions


def getScreenInfo():
    return {"x": win32api.GetSystemMetrics(0), "y": win32api.GetSystemMetrics(1)}


def getStartingpoint():
    return getCursorPos()


def getEndpoint():
    return getCursorPos()


def getRectangle():

    # Source: https://stackoverflow.com/a/41930485/5593051
    state_left = win32api.GetKeyState(0x01)  # Left button down = 0 or 1. Button up = -127 or -128
    state_right = win32api.GetKeyState(0x02)  # Right button down = 0 or 1. Button up = -127 or -128

    while True:
        a = win32api.GetKeyState(0x01)
        b = win32api.GetKeyState(0x02)

        if a != state_left:  # Button state changed
            state_left = a
            if a < 0:
                print('Left Button Pressed')
                pos_start = getStartingpoint()
            else:
                print('Left Button Released')
                pos_end = getEndpoint()
                break

    print(pos_start)
    print(pos_end)

    calcScreenshotFrame(pos_start, pos_end)


def calcScreenshotFrame(pos_start, pos_end):
    # If dragging began from top
    if pos_start['x'] < pos_end['x']:
        left = pos_start['x']
        right = pos_end['x']
        top = pos_start['y']
        bottom = pos_end['y']
    # If dragging began from bottom
    else:
        left = pos_end['x']
        right = pos_start['x']
        top = pos_end['y']
        bottom = pos_start['y']

    print("Screenshot needs to be taken from: x:", left, "->", right, "and y:", top, "->", bottom)


if __name__ == '__main__':
    print("This is a Subfile from grail, it can't be executed on its own.")
    exit()