import typing
import pymem
from pymem import pattern
from pymem.exception import ProcessNotFound, ProcessError, MemoryReadError, WinAPIError

from CommonClient import logger
from worlds.jakanddaxter.locs import CellLocations as Cells, ScoutLocations as Flies

# Some helpful constants.
next_cell_index_offset = 0    # Each of these is an uint64, so 8 bytes.
next_buzzer_index_offset = 8  # Each of these is an uint64, so 8 bytes.
cells_offset = 16
buzzers_offset = 420          # cells_offset + (sizeof uint32 * 101 cells) = 16 + (4 * 101)


# buzzers_offset
# + (sizeof uint32 * 112 flies)  <-- The buzzers themselves.
# + (sizeof uint8 * 116 tasks)   <-- A "cells-received" array for the game to handle new ownership logic.
# = 420 + (4 * 112) + (1 * 116)
end_marker_offset = 984


class JakAndDaxterMemoryReader:
    marker: typing.ByteString
    goal_address = None
    connected: bool = False
    initiated_connect: bool = False

    # The memory reader just needs the game running.
    gk_process: pymem.process = None

    location_outbox = []
    outbox_index = 0

    def __init__(self, marker: typing.ByteString = b'UnLiStEdStRaTs_JaK1\x00'):
        self.marker = marker
        self.connect()

    async def main_tick(self, location_callback: typing.Callable):
        if self.initiated_connect:
            await self.connect()
            self.initiated_connect = False

        if self.connected:
            try:
                self.gk_process.read_bool(self.gk_process.base_address)  # Ping to see if it's alive.
            except (ProcessError, MemoryReadError, WinAPIError):
                logger.error("The gk process has died. Restart the game and run \"/memr connect\" again.")
                self.connected = False
        else:
            return

        # Read the memory address to check the state of the game.
        self.read_memory()
        location_callback(self.location_outbox)  # TODO - I forgot why call this here when it's already down below...

        # Checked Locations in game. Handle the entire outbox every tick until we're up to speed.
        if len(self.location_outbox) > self.outbox_index:
            location_callback(self.location_outbox)
            self.outbox_index += 1

    async def connect(self):
        try:
            self.gk_process = pymem.Pymem("gk.exe")  # The GOAL Kernel
            logger.info("Found the gk process: " + str(self.gk_process.process_id))
        except ProcessNotFound:
            logger.error("Could not find the gk process.")
            self.connected = False
            return

        # If we don't find the marker in the first loaded module, we've failed.
        modules = list(self.gk_process.list_modules())
        marker_address = pattern.pattern_scan_module(self.gk_process.process_handle, modules[0], self.marker)
        if marker_address:
            # At this address is another address that contains the struct we're looking for: the game's state.
            # From here we need to add the length in bytes for the marker and 4 bytes of padding,
            # and the struct address is 8 bytes long (it's u64).
            goal_pointer = marker_address + len(self.marker) + 4
            self.goal_address = int.from_bytes(self.gk_process.read_bytes(goal_pointer, 8),
                                               byteorder="little",
                                               signed=False)
            logger.info("Found the archipelago memory address: " + str(self.goal_address))
            self.connected = True
        else:
            logger.error("Could not find the archipelago memory address.")
            self.connected = False

        if self.connected:
            logger.info("The Memory Reader is ready!")

    def print_status(self):
        logger.info("Memory Reader Status:")
        logger.info("   Game process ID: " + (str(self.gk_process.process_id) if self.gk_process else "None"))
        logger.info("   Game state memory address: " + str(self.goal_address))
        logger.info("   Last location checked: " + (str(self.location_outbox[self.outbox_index])
                                                    if self.outbox_index else "None"))

    def read_memory(self) -> typing.List[int]:
        try:
            next_cell_index = int.from_bytes(
                self.gk_process.read_bytes(self.goal_address, 8),
                byteorder="little",
                signed=False)
            next_buzzer_index = int.from_bytes(
                self.gk_process.read_bytes(self.goal_address + next_buzzer_index_offset, 8),
                byteorder="little",
                signed=False)

            for k in range(0, next_cell_index):
                next_cell = int.from_bytes(
                    self.gk_process.read_bytes(self.goal_address + cells_offset + (k * 4), 4),
                    byteorder="little",
                    signed=False)
                cell_ap_id = Cells.to_ap_id(next_cell)
                if cell_ap_id not in self.location_outbox:
                    self.location_outbox.append(cell_ap_id)
                    logger.info("Checked power cell: " + str(next_cell))

            for k in range(0, next_buzzer_index):
                next_buzzer = int.from_bytes(
                    self.gk_process.read_bytes(self.goal_address + buzzers_offset + (k * 4), 4),
                    byteorder="little",
                    signed=False)
                buzzer_ap_id = Flies.to_ap_id(next_buzzer)
                if buzzer_ap_id not in self.location_outbox:
                    self.location_outbox.append(buzzer_ap_id)
                    logger.info("Checked scout fly: " + str(next_buzzer))

        except (ProcessError, MemoryReadError, WinAPIError):
            logger.error("The gk process has died. Restart the game and run \"/memr connect\" again.")
            self.connected = False

        return self.location_outbox