import os
import platform
import random
import re
import subprocess
import threading
import uuid
import zipfile
from time import sleep

import psutil
import requests
from tqdm import tqdm

__version__ = "0.1.6"

MAX_RETRY_TIMES = 10
UBUNTU_ARM_URL = "https://huggingface.co/datasets/xlangai/ubuntu_arm/resolve/main/Ubuntu.zip"
UBUNTU_X86_URL = "https://huggingface.co/datasets/xlangai/ubuntu_x86/resolve/main/Ubuntu.zip"
REGISTRY_PATH = '.vms'
REGISTRY_IDX_PATH = ".vms_idx"
update_lock = threading.Lock()


class VirtualMachineManager:
    def __init__(self, registry_path=REGISTRY_PATH, registry_idx_path=REGISTRY_IDX_PATH):
        self.registry_path = registry_path
        self.registry_idx_path = registry_idx_path
        self.lock = threading.Lock()
        self.initialize_registry()

    def initialize_registry(self):
        with self.lock:  # Locking during initialization
            if not os.path.exists(self.registry_path):
                with open(self.registry_path, 'w') as file:
                    file.write('')
            if not os.path.exists(self.registry_idx_path):
                with open(self.registry_idx_path, 'w') as file:
                    file.write('0')

    def add_vm(self, vm_path):
        with self.lock:
            with open(self.registry_path, 'r') as file:
                lines = file.readlines()
                new_lines = lines + [f'{vm_path}|free\n']
            with open(self.registry_path, 'w') as file:
                file.writelines(new_lines)

    def occupy_vm(self, vm_path, pid):
        with self.lock:
            new_lines = []
            with open(self.registry_path, 'r') as file:
                lines = file.readlines()
                for line in lines:
                    registered_vm_path, _ = line.strip().split('|')
                    if registered_vm_path == vm_path:
                        new_lines.append(f'{registered_vm_path}|{pid}\n')
                    else:
                        new_lines.append(line)
            with open(self.registry_path, 'w') as file:
                file.writelines(new_lines)

    def release_vm(self, vm_path):
        with self.lock:  # Lock when modifying the registry
            new_lines = []
            with open(self.registry_path, 'r') as file:
                lines = file.readlines()
                for line in lines:
                    registered_vm_path, _ = line.strip().split('|')
                    if registered_vm_path != vm_path:
                        new_lines.append(line)
                    else:
                        new_lines.append(f'{registered_vm_path}|free\n')
            with open(self.registry_path, 'w') as file:
                file.writelines(new_lines)

    def check_and_clean(self):
        with self.lock:  # Lock when cleaning up the registry
            active_pids = {p.pid for p in psutil.process_iter()}
            new_lines = []
            with open(self.registry_path, 'r') as file:
                lines = file.readlines()
                for line in lines:
                    vm_path, pid_str = line.strip().split('|')
                    if pid_str == "free":
                        new_lines.append(line)
                        continue

                    if int(pid_str) in active_pids:
                        new_lines.append(line)
                    else:
                        new_lines.append(f'{vm_path}|free\n')
            with open(self.registry_path, 'w') as file:
                file.writelines(new_lines)

    def list_vms(self):
        with self.lock:  # Lock when reading the registry
            all_vms = []
            with open(self.registry_path, 'r') as file:
                lines = file.readlines()
                for line in lines:
                    vm_path, pid_str = line.strip().split('|')
                    all_vms.append((vm_path, pid_str))
            return all_vms

    def list_free_vms(self):
        with self.lock:  # Lock when reading the registry
            free_vms = []
            with open(self.registry_path, 'r') as file:
                lines = file.readlines()
                for line in lines:
                    vm_path, pid_str = line.strip().split('|')
                    if pid_str == "free":
                        free_vms.append((vm_path, pid_str))
            return free_vms

    def generate_new_vm_name(self):
        with self.lock:  # Lock when generating a new path
            with open(self.registry_idx_path, 'r') as file:
                idx = int(file.read())

            new_name = f"Ubuntu{idx}"

            with open(self.registry_idx_path, 'w') as file:
                file.write(str(idx + 1))

        return new_name


def _update_vm(vmx_path, target_vm_name):
    """Update the VMX file with the new VM name and other parameters, so that the VM can be started successfully without conflict with the original VM."""
    with update_lock:
        dir_path, vmx_file = os.path.split(vmx_path)

        def _generate_mac_address():
            # VMware MAC address range starts with 00:0c:29
            mac = [0x00, 0x0c, 0x29,
                   random.randint(0x00, 0x7f),
                   random.randint(0x00, 0xff),
                   random.randint(0x00, 0xff)]
            return ':'.join(map(lambda x: "%02x" % x, mac))

        # Backup the original file
        with open(vmx_path, 'r') as file:
            original_content = file.read()

        # Generate new values
        new_uuid_bios = str(uuid.uuid4())
        new_uuid_location = str(uuid.uuid4())
        new_mac_address = _generate_mac_address()
        new_vmci_id = str(random.randint(-2147483648, 2147483647))  # Random 32-bit integer

        # Update the content
        updated_content = re.sub(r'displayName = ".*?"', f'displayName = "{target_vm_name}"', original_content)
        updated_content = re.sub(r'uuid.bios = ".*?"', f'uuid.bios = "{new_uuid_bios}"', updated_content)
        updated_content = re.sub(r'uuid.location = ".*?"', f'uuid.location = "{new_uuid_location}"', updated_content)
        updated_content = re.sub(r'ethernet0.generatedAddress = ".*?"',
                                 f'ethernet0.generatedAddress = "{new_mac_address}"',
                                 updated_content)
        updated_content = re.sub(r'vmci0.id = ".*?"', f'vmci0.id = "{new_vmci_id}"', updated_content)

        # Write the updated content back to the file
        with open(vmx_path, 'w') as file:
            file.write(updated_content)

        print(".vmx file updated successfully.")

        vmx_file_base_name = os.path.splitext(vmx_file)[0]

        assert vmx_file == "Ubuntu.vmx", "The VMX file should be named 'Ubuntu.vmx'."
        files_to_rename = ['vmx', 'nvram', 'vmsd', 'vmxf']

        for ext in files_to_rename:
            original_file = os.path.join(dir_path, f"{vmx_file_base_name}.{ext}")
            target_file = os.path.join(dir_path, f"{target_vm_name}.{ext}")
            os.rename(original_file, target_file)

        # Update the dir_path to the target vm_name, only replace the last character
        # Split the path into parts up to the last folder
        path_parts = dir_path.rstrip(os.sep).split(os.sep)
        path_parts[-1] = target_vm_name
        target_dir_path = os.sep.join(path_parts)
        os.rename(dir_path, target_dir_path)

        print("VM files renamed successfully.")


def _install_virtual_machine(vm_name, working_dir="./vm_data", downloaded_file_name="Ubuntu.zip", original_vm_name="Ubuntu"):
    os.makedirs(working_dir, exist_ok=True)
    def __download_and_unzip_vm():
        # Determine the platform and CPU architecture to decide the correct VM image to download
        if platform.machine() == 'arm64':  # macOS with Apple Silicon
            url = UBUNTU_ARM_URL
        elif platform.machine().lower() in ['amd64', "x86_64"]:
            url = UBUNTU_X86_URL
        else:
            raise Exception("Unsupported platform or architecture")

        # Download the virtual machine image
        print("Downloading the virtual machine image...")
        downloaded_size = 0

        while True:
            downloaded_file_path = os.path.join(working_dir, downloaded_file_name)
            headers = {}
            if os.path.exists(downloaded_file_path):
                downloaded_size = os.path.getsize(downloaded_file_path)
                headers["Range"] = f"bytes={downloaded_size}-"

            with requests.get(url, headers=headers, stream=True) as response:
                if response.status_code == 416:
                    # This means the range was not satisfiable, possibly the file was fully downloaded
                    print("Fully downloaded or the file sized changed.")
                    break

                response.raise_for_status()
                total_size = int(response.headers.get('content-length', 0))

                with open(downloaded_file_path, "ab") as file, tqdm(
                        desc="Progress",
                        total=total_size,
                        unit='iB',
                        unit_scale=True,
                        unit_divisor=1024,
                        initial=downloaded_size,
                        ascii=True
                ) as progress_bar:
                    try:
                        for data in response.iter_content(chunk_size=1024):
                            size = file.write(data)
                            progress_bar.update(size)
                    except (requests.exceptions.RequestException, IOError) as e:
                        print(f"Download error: {e}")
                        sleep(1)  # Wait for 1 second before retrying
                        print("Retrying...")
                    else:
                        print("Download succeeds.")
                        break  # Download completed successfully

        # Unzip the downloaded file
        print("Unzipping the downloaded file...☕️")
        with zipfile.ZipFile(downloaded_file_path, 'r') as zip_ref:
            zip_ref.extractall(os.path.join(working_dir, vm_name))
        print("Files have been successfully extracted to the directory:", os.path.join(working_dir, vm_name))

    vm_path = os.path.join(working_dir, vm_name, vm_name, vm_name + ".vmx")

    # Execute the function to download and unzip the VM, and update the vm metadata
    if not os.path.exists(vm_path):
        __download_and_unzip_vm()
        _update_vm(os.path.join(working_dir, vm_name, original_vm_name, original_vm_name + ".vmx"), vm_name)
    else:
        print(f"Virtual machine exists: {vm_path}")

    # Determine the platform of the host machine and decide the parameter for vmrun
    def get_vmrun_type():
        if platform.system() == 'Windows' or platform.system() == 'Linux':
            return '-T ws'
        elif platform.system() == 'Darwin':  # Darwin is the system name for macOS
            return '-T fusion'
        else:
            raise Exception("Unsupported operating system")

    # Start the virtual machine
    subprocess.run(f'vmrun {get_vmrun_type()} start "{vm_path}" nogui', shell=True)
    print("Starting virtual machine...")

    # Get the IP address of the virtual machine
    for i in range(MAX_RETRY_TIMES):
        get_vm_ip = subprocess.run(f'vmrun {get_vmrun_type()} getGuestIPAddress "{vm_path}" -wait', shell=True,
                                   capture_output=True,
                                   text=True)
        if "Error" in get_vm_ip.stdout:
            print("Retry on getting IP")
            continue
        print("Virtual machine IP address:", get_vm_ip.stdout.strip())
        break

    vm_ip = get_vm_ip.stdout.strip()

    def is_url_accessible(url, timeout=1):
        try:
            response = requests.head(url, timeout=timeout)
            return response.status_code == 200
        except requests.exceptions.RequestException:
            return False

    url = f"http://{vm_ip}:5000/screenshot"
    check_url = is_url_accessible(url)

    # Function used to check whether the virtual machine is ready
    def download_screenshot(ip):
        url = f"http://{ip}:5000/screenshot"
        try:
            # max trey times 1, max timeout 1
            response = requests.get(url, timeout=(1, 1))
            if response.status_code == 200:
                return True
        except Exception as e:
            print(f"Error: {e}")
            print(f"Type: {type(e).__name__}")
            print(f"Error detail: {str(e)}")
            sleep(2)
        return False

    # Try downloading the screenshot until successful
    while not download_screenshot(vm_ip):
        print("Check whether the virtual machine is ready...")

    print("Virtual machine is ready. Start to make a snapshot on the virtual machine. It would take a while...")

    # Create a snapshot of the virtual machine
    subprocess.run(f'vmrun {get_vmrun_type()} snapshot "{vm_path}" "init_state"', shell=True)
    print("Snapshot created.")

    return vm_path


def _get_vm_path():
    vm_manager = VirtualMachineManager(REGISTRY_PATH)
    vm_manager.check_and_clean()
    free_vms_paths = vm_manager.list_free_vms()
    if len(free_vms_paths) == 0:
        # No free virtual machine available, generate a new one
        print("No free virtual machine available. Generating a new one, which would take a while...☕")
        new_vm_name = vm_manager.generate_new_vm_name()
        new_vm_path = _install_virtual_machine(new_vm_name)
        vm_manager.add_vm(new_vm_path)
        vm_manager.occupy_vm(new_vm_path, os.getpid())
        return new_vm_path
    else:
        # Choose the first free virtual machine
        chosen_vm_path = free_vms_paths[0][0]
        vm_manager.occupy_vm(chosen_vm_path, os.getpid())
        return chosen_vm_path