#
import pifacedigitalio
import pifacecommon.mcp23s17
import time
from subprocess import call
import sys

button_count = 2
longpress_delay = 0.6           # minimum time in s for a long press
inter_press_max_delay = 0.8     # maximum time in s between two presses
button_debounce_wait = 0.08     # time in s befor signal stabilizes

pin = {
    0: {
     'shortpress': {
         'count': 0,
         'last_unpress': 0
     },
     'last_unpress': 0,
     'last_press': 0,
   'sched_time': 0
    },
    1: {
     'shortpress': {
         'count': 0,
         'last_unpress': 0
     },
     'last_unpress': 0,
     'last_press': 0,
   'sched_time': 0
    }
}

# dirty workaround to disable reset of output pins
def init_board_no_power_off(self):
    ioconfig = (
        pifacecommon.mcp23s17.BANK_OFF |
        pifacecommon.mcp23s17.INT_MIRROR_OFF |
        pifacecommon.mcp23s17.SEQOP_OFF |
        pifacecommon.mcp23s17.DISSLW_OFF |
        pifacecommon.mcp23s17.HAEN_ON |
        pifacecommon.mcp23s17.ODR_OFF |
        pifacecommon.mcp23s17.INTPOL_LOW
    )
    self.iocon.value = ioconfig
    if self.iocon.value != ioconfig:
        raise pifacedigitalio.NoPiFaceDigitalDetectedError(
            "No PiFace Digital board detected (hardware_addr={h}, "
            "bus={b}, chip_select={c}).".format(
                h=self.hardware_addr, b=self.bus, c=self.chip_select))
    else:
        self.iodira.value = 0  # GPIOA as outputs
        self.iodirb.value = 0xFF  # GPIOB as inputs
        self.gppub.value = 0xFF  # input pullups on
        self.enable_interrupts()

setattr(pifacedigitalio.PiFaceDigital, 'init_board', init_board_no_power_off)

def chch_status_output(pfd):
    # update status file
    f = open("/tmp/status", 'w')
    status = "geschlossen"
    for i in range(button_count):
        if pfd.output_pins[i].value != 0:
            status = "geöffnet"
            break
    try:
        f.truncate(0)
        f.write(status)
    except OSError:
        sys.stderr.write("Can not write to status file\n")
    # start / stop lounge VM
    if pfd.output_pins[0].value != 0:
        try:
            call(["/home/automation/proxmox-api-bash/vm_control.sh","chch","lounge","pve","310","start"])
        except:
            sys.stderr.write("Could not start lounge VM\n")
    else:
        try:
            call(["/home/automation/proxmox-api-bash/vm_control.sh","chch","lounge","pve","310","shutdown"])
        except:
            sys.stderr.write("Could not start lounge VM\n")

def exec_chch_button_cmd(event):
    c_pin = pin[event.pin_num]
    print({'event':{'pin':event.pin_num,'at':c_pin['last_unpress'],'state':'executing'}})
    count = c_pin['shortpress']['count']
    # a longpress happend
    if c_pin['last_unpress'] > c_pin['shortpress']['last_unpress']:
        # '-' all off
        if count == 0:
            for i in range(button_count):
                event.chip.output_pins[i].turn_off()
        # '. -' all on
        elif count == 1:
            for i in range(button_count):
                event.chip.output_pins[i].turn_on()
        else:
            sys.stderr.write("No mode with " + str(count) +  " short press and a long press\n")
    else:
        # '.' room specific function
        if count == 1:
            if event.pin_num == 0:
                call(["/home/automation/chch-power/light.sh","1"])
            elif event.pin_num == 1:
                call(["/home/automation/chch-power/light.sh","2"])
            else:
                sys.stderr.write("No room specific function for room " + str(event.pin_num) + "\n")
        # '. .' toggle current room
        elif count == 2:
            event.chip.output_pins[event.pin_num].toggle()
        else:
            sys.stderr.write("No mode with " + str(count) + " short press at pin " + str(event.pin_num) + "\n")
    chch_status_output(event.chip)
    # cleanup
    c_pin['last_unpress'] = 0
    c_pin['last_press'] = 0
    c_pin['shortpress']['count'] = 0

# count the number of short press
def switch_shortpressed(event):
    c_pin = pin[event.pin_num]
    if c_pin['shortpress']['count'] == 0:
        c_pin['shortpress']['last_unpress'] = c_pin['last_unpress']
    # determine delay between last rise of the switch and current rise
    shortpress_delay = c_pin['last_unpress'] - c_pin['shortpress']['last_unpress']
    if shortpress_delay > inter_press_max_delay:
        c_pin['shortpress']['count'] = 1
    else:
        c_pin['shortpress']['count'] += 1
    c_pin['shortpress']['last_unpress'] = c_pin['last_unpress']
    print({'shortpress':{'delay':shortpress_delay,'count':c_pin['shortpress']['count']}})

def switch_pressed(event):
    event_time = time.time()
    c_pin = pin[event.pin_num]
    # debouncing
    c_pin['last_press'] = 0
    time.sleep(button_debounce_wait)
    if event.chip.input_pins[event.pin_num].value == 0:
        return
    # remove scheduled event
    c_pin['sched_time'] = 0
    c_pin['last_press'] = event_time

def switch_unpressed(event):
    event_time = time.time()
    c_pin = pin[event.pin_num]
    if c_pin['last_press'] == 0:
        return
    c_pin['last_unpress'] = event_time
    press_time = c_pin['last_unpress'] - c_pin['last_press']
    if press_time < longpress_delay:
        # parse data inter_press_max_delay seconds after no event
        c_pin['sched_time'] = c_pin['last_unpress'] + inter_press_max_delay
        print({'event':{'pin':event.pin_num,'at':c_pin['last_unpress'],'in':inter_press_max_delay,'state':'scheduled'}})
        switch_shortpressed(event)
    else:
        c_pin['sched_time'] = 0
        exec_chch_button_cmd(event)

if __name__ == "__main__":
    listener = pifacedigitalio.InputEventListener()
    for i in range(button_count):
        listener.register(i, pifacedigitalio.IODIR_ON, switch_pressed)
        listener.register(i, pifacedigitalio.IODIR_OFF, switch_unpressed)
    listener.activate()
    chch_status_output(listener.chip)
    while True:
        for i in range(button_count):
            c_pin = pin[i]
            if time.time() > c_pin['sched_time'] and c_pin['sched_time'] != 0:
                c_pin['sched_time'] = 0
                setattr(listener, 'pin_num', i)
                exec_chch_button_cmd(listener)
        time.sleep(0.01)