#!/usr/bin/env python3.7
# Copyright (c) 2011-2019 Eric Froemling
#
# Permission is hereby granted, free of charge, to any person obtaining a copy
# of this software and associated documentation files (the "Software"), to deal
# in the Software without restriction, including without limitation the rights
# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
# copies of the Software, and to permit persons to whom the Software is
# furnished to do so, subject to the following conditions:
#
# The above copyright notice and this permission notice shall be included in
# all copies or substantial portions of the Software.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
# SOFTWARE.
# -----------------------------------------------------------------------------
"""A tool for interacting with ballistica's cloud services.
This facilitates workflows such as creating asset-bundles, etc.
"""

from __future__ import annotations

import sys
import os
from enum import Enum
from pathlib import Path
from typing import TYPE_CHECKING
import urllib.request
import urllib.parse
import urllib.error
from dataclasses import dataclass
import json
import subprocess

if TYPE_CHECKING:
    from typing import Optional, Dict, Any

# Version is sent to the master-server with all commands. Can be incremented
# if we need to change behavior server-side to go along with client changes.
VERSION = 1

TOOL_NAME = 'cloudtool'

# Set CLOUDTOOL_LOCAL env var to 1 to test with a locally-run master-server.
MASTER_SERVER_ADDRESS = ('http://localhost:23524'
                         if os.environ.get('CLOUDTOOL_LOCAL') == '1' else
                         'https://bamaster.appspot.com')
USER_AGENT_STRING = 'cloudtool'
CACHE_DIR = Path('.cache/cloudtool')
CACHE_DATA_PATH = Path(CACHE_DIR, 'state')

CLRHDR = '\033[95m'  # Header.
CLRGRN = '\033[92m'  # Green.
CLRBLU = '\033[94m'  # Glue.
CLRRED = '\033[91m'  # Red.
CLREND = '\033[0m'  # End.

CMD_LOGIN = 'login'
CMD_LOGOUT = 'logout'
CMD_PUTASSET = 'putasset'
CMD_HELP = 'help'

ASSET_PATH_VALID_CHARS = 'abcdefghijklmnopqrstuvwxyz0123456789_'
ASSET_PATH_MAX_LENGTH = 128


@dataclass
class StateData:
    """Persistent state data stored to disk."""
    login_token: Optional[str] = None


@dataclass
class Response:
    """Response data from the master server for a command."""
    message: Optional[str]
    error: Optional[str]
    data: Any


class CleanError(Exception):
    """Exception resulting in a clean error string print and exit."""


class AssetType(Enum):
    """Types for asset files."""
    TEXTURE = 'texture'
    SOUND = 'sound'


class Asset:
    """Data for a single asset."""

    def __init__(self, assettype: AssetType) -> None:
        self.assettype = assettype
        print('INITING ASSET OF TYPE', assettype)


def validate_asset_path(path: str) -> None:
    """Throw an exception on an invalid asset path."""
    names = path.split('/')
    for name in names:
        if not name:
            raise CleanError(f'Found empty component in asset path "{path}".')
        for char in name:
            if char not in ASSET_PATH_VALID_CHARS:
                raise CleanError(
                    f'Found invalid char "{char}" in asset path "{path}".')


class AssetBundle:
    """Data for local or remote asset bundles."""

    def __init__(self) -> None:
        self.assets: Dict[str, Asset] = {}

    @classmethod
    def load_from_disk(cls, path: Path) -> AssetBundle:
        """Load an asset bundle from an existing one on disk."""
        import yaml
        indexfilename = 'assetbundle.yaml'
        bundle = AssetBundle()

        if not path.is_dir():
            raise CleanError(f'Directory not found: "{path}"')

        with open(Path(path, indexfilename)) as infile:
            index = yaml.safe_load(infile)
        if not isinstance(index, dict):
            raise CleanError(f'Root dict not found in {indexfilename}')
        assets = index.get('assets')
        if not isinstance(assets, dict):
            raise CleanError(f'No "assets" dict found in {indexfilename}')
        for assetpath, assetdata in assets.items():
            validate_asset_path(assetpath)
            if len(assetpath) > ASSET_PATH_MAX_LENGTH:
                raise CleanError(f'Asset path is too long: "{assetpath}"')
            if not isinstance(assetdata, dict):
                raise CleanError(
                    f'Invalid asset data for {assetpath} in {indexfilename}')
            assettypestr = assetdata.get('type')
            if not isinstance(assettypestr, str):
                raise CleanError(
                    f'Invalid asset type for {assetpath} in {indexfilename}')
            assettype = AssetType(assettypestr)

            print('looking at', assetpath, assetdata)
            bundle.assets[assetpath] = Asset(assettype)

        return bundle


class App:
    """Context for a run of the tool."""

    def __init__(self) -> None:
        self._state = StateData()

    def run(self) -> None:
        """Run the tool."""

        # Make reasonably sure we're being run from project root.
        if not os.path.exists(f'tools/{TOOL_NAME}'):
            raise CleanError(
                'This tool must be run from ballistica project root.')

        # Also run project prereqs checks so we can hopefully inform the user
        # of missing python modules/etc. instead of just failing cryptically.
        try:
            subprocess.run(['make', '--quiet', 'prereqs'], check=True)
        except subprocess.CalledProcessError:
            raise CleanError('"make prereqs" check failed. '
                             'Install missing requirements and try again.')

        self._load_cache()

        if len(sys.argv) < 2:
            raise CleanError(
                f'Invalid args. Run "cloudtool help" for usage info.')

        cmd = sys.argv[1]
        if cmd == CMD_LOGIN:
            self.do_login()
        elif cmd == CMD_LOGOUT:
            self.do_logout()
        elif cmd == CMD_PUTASSET:
            self.do_putasset()
        else:
            # For all other commands, simply pass them to the server verbatim.
            self.do_misc_command()

        self._save_cache()

    def _load_cache(self) -> None:
        if not os.path.exists(CACHE_DATA_PATH):
            return
        try:
            with open(CACHE_DATA_PATH, 'r') as infile:
                self._state = StateData(**json.loads(infile.read()))
        except Exception:
            print(CLRRED +
                  f'Error loading {TOOL_NAME} data; resetting to defaults.' +
                  CLREND)

    def _save_cache(self) -> None:
        if not CACHE_DIR.exists():
            CACHE_DIR.mkdir(parents=True, exist_ok=True)
        with open(CACHE_DATA_PATH, 'w') as outfile:
            outfile.write(json.dumps(self._state.__dict__))

    def _servercmd(self, cmd: str, data: Dict) -> Response:
        """Issue a command to the server and get a response."""

        # We do all communication through POST requests to the server.
        response_raw = urllib.request.urlopen(
            urllib.request.Request(
                (MASTER_SERVER_ADDRESS + '/cloudtoolcmd'),
                urllib.parse.urlencode({
                    'c': cmd,
                    'v': VERSION,
                    't': json.dumps(self._state.login_token),
                    'd': json.dumps(data)
                }).encode(), {'User-Agent': USER_AGENT_STRING}))
        output = json.loads(response_raw.read().decode())
        assert isinstance(output, dict)
        response = Response(message=output['m'],
                            data=output['d'],
                            error=output['e'])

        # Handle errors and messages which are common to all command types.
        if response.error is not None:
            raise CleanError(response.error)

        if response.message is not None:
            print(response.message)

        return response

    def do_login(self) -> None:
        """Run the login command."""

        if len(sys.argv) != 3:
            raise CleanError('Expected a login code.')

        login_code = sys.argv[2]
        response = self._servercmd('login', {'c': login_code})

        # If the command returned cleanly, we should have a token we can use
        # to log in.
        token = response.data['logintoken']
        assert isinstance(token, str)

        aname = response.data['accountname']
        assert isinstance(aname, str)

        print(f'{CLRGRN}Now logged in as {aname}.{CLREND}')
        self._state.login_token = token

    def do_logout(self) -> None:
        """Run the logout command."""
        self._state.login_token = None
        print(f'{CLRGRN}Cloudtool is now logged out.{CLREND}')

    def do_putasset(self) -> None:
        """Run a putasset command."""

        if len(sys.argv) != 3:
            raise CleanError('Expected a path to an assetpackage directory.')

        path = Path(sys.argv[2])
        _bundle = AssetBundle.load_from_disk(path)

    def do_misc_command(self) -> None:
        """Run a miscellaneous command."""

        # We don't do anything special with the response here; the normal
        # error-handling/message-printing is all that happens.
        self._servercmd('misc', {'a': sys.argv[1:]})


if __name__ == '__main__':
    try:
        App().run()
    except CleanError as exc:
        if str(exc):
            print(f'{CLRRED}{exc}{CLREND}')
        sys.exit(-1)