import bin #this is at the end of the script in case any functions from bin
#depend on anything here
from circuitos.exceptions import *
from circuitos.apploader import get_app
import circuitos.apploader # apploader hack
import time
import usb_cdc

class App:
    def __init__(self, os, pid, name, *argv):
        self.os = os
        self.pid = pid
        self.name = name
        self.store = {}
        self.next_function = 'main'
        self.run_at = -1
        self.argv = (self,) + argv
        self.waiting_for = -1

    def iterate(self):
        if time.monotonic() >= self.run_at and not self.waiting_for in self.os.apps:
            getattr(self, f'F_{self.next_function}')()

    @property
    def console(self):
        if self.pid == self.os.controllers[-1]:
            return self.os.console
        else:
            raise NotConsoleController(self.os.controllers[-1])

    def transfer_console(self, recipient):
        if self.pid == self.os.controllers[-1]:
            self.os.controllers.append(recipient)
        else:
            raise NotConsoleController(self.os.controllers[-1])

    def jump(self, function):
        self.next_function = function

    def sleep(self, seconds):
        self.run_at = time.monotonic() + seconds

    def exec(self, command, *argv):
        self.os.apps[self.pid] = get_app(command)(self.os, self.pid, command, *argv)

    def wait(self, pid):
        self.waiting_for = pid

    def end_wait(self):
        self.waiting_for = -1

    def on_exit(self):
        pass

    def exit(self):
        del self.os.apps[self.pid]

apploader.App = App # apploader hack

class OS:
    def __init__(self):
        self.apps = {}
        self.next_new = 0
        self.controllers = [0]
        self.console = usb_cdc.console
        usb_cdc.console.timeout = 0
        self.next_pidi = 0
        self.launch('init')

    def iterate(self):
        pid = list(self.apps.keys())[self.next_pidi]
        function = self.apps[pid].iterate

        function()

        try:
            self.apps[pid]
            # If this succeds, the app did not exit and next_pidi should
            # be incremented
            self.next_pidi += 1
        except KeyError:
            # If self.apps[pid] failed, the app exited and next_pidi
            # should not be incremented
            pass
        self.next_pidi = self.next_pidi % len(self.apps)

        while not self.controllers[-1] in self.apps.keys():
            self.controllers.pop()

    def launch(self, app, *argv):
        self.apps[self.next_new] = get_app(app)(self, self.next_new, app, *argv)
        self.next_new += 1
        return self.next_new - 1

    def kill(self, pid):
        try:
            del self.apps[pid]
        except KeyError:
            raise(NoSuchProcess(pid))

def run():
    os = OS()
    while True:
        os.iterate()