"""
This is the main file for the runtime client.
It is responsible for executing actions received from OpenHands backend and producing observations.

NOTE: this will be executed inside the docker sandbox.
"""

import argparse
import asyncio
import base64
import io
import mimetypes
import os
import shutil
import tempfile
import time
from contextlib import asynccontextmanager
from pathlib import Path
from zipfile import ZipFile

from fastapi import Depends, FastAPI, HTTPException, Request, UploadFile
from fastapi.exceptions import RequestValidationError
from fastapi.responses import JSONResponse, StreamingResponse
from fastapi.security import APIKeyHeader
from pydantic import BaseModel
from starlette.exceptions import HTTPException as StarletteHTTPException
from uvicorn import run

from openhands.core.logger import openhands_logger as logger
from openhands.events.action import (
    Action,
    BrowseInteractiveAction,
    BrowseURLAction,
    CmdRunAction,
    FileReadAction,
    FileWriteAction,
    IPythonRunCellAction,
)
from openhands.events.observation import (
    CmdOutputObservation,
    ErrorObservation,
    FileReadObservation,
    FileWriteObservation,
    IPythonRunCellObservation,
    Observation,
)
from openhands.events.serialization import event_from_dict, event_to_dict
from openhands.runtime.browser import browse
from openhands.runtime.browser.browser_env import BrowserEnv
from openhands.runtime.plugins import ALL_PLUGINS, JupyterPlugin, Plugin, VSCodePlugin
from openhands.runtime.utils.bash import BashSession
from openhands.runtime.utils.files import insert_lines, read_lines
from openhands.runtime.utils.runtime_init import init_user_and_working_directory
from openhands.runtime.utils.system import check_port_available
from openhands.utils.async_utils import call_sync_from_async, wait_all


class ActionRequest(BaseModel):
    action: dict


ROOT_GID = 0
INIT_COMMANDS = [
    'git config --global user.name "openhands" && git config --global user.email "openhands@all-hands.dev" && alias git="git --no-pager"',
]

SESSION_API_KEY = os.environ.get('SESSION_API_KEY')
api_key_header = APIKeyHeader(name='X-Session-API-Key', auto_error=False)


def verify_api_key(api_key: str = Depends(api_key_header)):
    if SESSION_API_KEY and api_key != SESSION_API_KEY:
        raise HTTPException(status_code=403, detail='Invalid API Key')
    return api_key


class ActionExecutor:
    """ActionExecutor is running inside docker sandbox.
    It is responsible for executing actions received from OpenHands backend and producing observations.
    """

    def __init__(
        self,
        plugins_to_load: list[Plugin],
        work_dir: str,
        username: str,
        user_id: int,
        browsergym_eval_env: str | None,
    ) -> None:
        self.plugins_to_load = plugins_to_load
        self._initial_pwd = work_dir
        self.username = username
        self.user_id = user_id
        _updated_user_id = init_user_and_working_directory(
            username=username, user_id=self.user_id, initial_pwd=work_dir
        )
        if _updated_user_id is not None:
            self.user_id = _updated_user_id

        self.bash_session = BashSession(
            work_dir=work_dir,
            username=username,
        )

        self.lock = asyncio.Lock()
        self.plugins: dict[str, Plugin] = {}
        self.browser = BrowserEnv(browsergym_eval_env)
        self.start_time = time.time()
        self.last_execution_time = self.start_time

    @property
    def initial_pwd(self):
        return self._initial_pwd

    async def ainit(self):
        await wait_all(
            (self._init_plugin(plugin) for plugin in self.plugins_to_load),
            timeout=30,
        )

        # This is a temporary workaround
        # TODO: refactor AgentSkills to be part of JupyterPlugin
        # AFTER ServerRuntime is deprecated
        if 'agent_skills' in self.plugins and 'jupyter' in self.plugins:
            obs = await self.run_ipython(
                IPythonRunCellAction(
                    code='from openhands.runtime.plugins.agent_skills.agentskills import *\n'
                )
            )
            logger.debug(f'AgentSkills initialized: {obs}')

        await self._init_bash_commands()
        logger.debug('Runtime client initialized.')

    async def _init_plugin(self, plugin: Plugin):
        await plugin.initialize(self.username)
        self.plugins[plugin.name] = plugin
        logger.debug(f'Initializing plugin: {plugin.name}')

        if isinstance(plugin, JupyterPlugin):
            await self.run_ipython(
                IPythonRunCellAction(
                    code=f'import os; os.chdir("{self.bash_session.pwd}")'
                )
            )

    async def _init_bash_commands(self):
        logger.debug(f'Initializing by running {len(INIT_COMMANDS)} bash commands...')
        for command in INIT_COMMANDS:
            action = CmdRunAction(command=command)
            action.timeout = 300
            logger.debug(f'Executing init command: {command}')
            obs = await self.run(action)
            assert isinstance(obs, CmdOutputObservation)
            logger.debug(
                f'Init command outputs (exit code: {obs.exit_code}): {obs.content}'
            )
            assert obs.exit_code == 0

        logger.debug('Bash init commands completed')

    async def run_action(self, action) -> Observation:
        async with self.lock:
            action_type = action.action
            logger.debug(f'Running action:\n{action}')
            observation = await getattr(self, action_type)(action)
            logger.debug(f'Action output:\n{observation}')
            return observation

    async def run(
        self, action: CmdRunAction
    ) -> CmdOutputObservation | ErrorObservation:
        obs = await call_sync_from_async(self.bash_session.run, action)
        return obs

    async def run_ipython(self, action: IPythonRunCellAction) -> Observation:
        if 'jupyter' in self.plugins:
            _jupyter_plugin: JupyterPlugin = self.plugins['jupyter']  # type: ignore
            # This is used to make AgentSkills in Jupyter aware of the
            # current working directory in Bash
            jupyter_pwd = getattr(self, '_jupyter_pwd', None)
            if self.bash_session.pwd != jupyter_pwd:
                logger.debug(
                    f'{self.bash_session.pwd} != {jupyter_pwd} -> reset Jupyter PWD'
                )
                reset_jupyter_pwd_code = (
                    f'import os; os.chdir("{self.bash_session.pwd}")'
                )
                _aux_action = IPythonRunCellAction(code=reset_jupyter_pwd_code)
                _reset_obs: IPythonRunCellObservation = await _jupyter_plugin.run(
                    _aux_action
                )
                logger.debug(
                    f'Changed working directory in IPython to: {self.bash_session.pwd}. Output: {_reset_obs}'
                )
                self._jupyter_pwd = self.bash_session.pwd

            obs: IPythonRunCellObservation = await _jupyter_plugin.run(action)
            obs.content = obs.content.rstrip()
            if action.include_extra:
                obs.content += (
                    f'\n[Jupyter current working directory: {self.bash_session.pwd}]'
                )
                obs.content += f'\n[Jupyter Python interpreter: {_jupyter_plugin.python_interpreter_path}]'
            return obs
        else:
            raise RuntimeError(
                'JupyterRequirement not found. Unable to run IPython action.'
            )

    def _resolve_path(self, path: str, working_dir: str) -> str:
        filepath = Path(path)
        if not filepath.is_absolute():
            return str(Path(working_dir) / filepath)
        return str(filepath)

    async def read(self, action: FileReadAction) -> Observation:
        # NOTE: the client code is running inside the sandbox,
        # so there's no need to check permission
        working_dir = self.bash_session.workdir
        filepath = self._resolve_path(action.path, working_dir)
        try:
            if filepath.lower().endswith(('.png', '.jpg', '.jpeg', '.bmp', '.gif')):
                with open(filepath, 'rb') as file:
                    image_data = file.read()
                    encoded_image = base64.b64encode(image_data).decode('utf-8')
                    mime_type, _ = mimetypes.guess_type(filepath)
                    if mime_type is None:
                        mime_type = 'image/png'  # default to PNG if mime type cannot be determined
                    encoded_image = f'data:{mime_type};base64,{encoded_image}'

                return FileReadObservation(path=filepath, content=encoded_image)
            elif filepath.lower().endswith('.pdf'):
                with open(filepath, 'rb') as file:
                    pdf_data = file.read()
                    encoded_pdf = base64.b64encode(pdf_data).decode('utf-8')
                    encoded_pdf = f'data:application/pdf;base64,{encoded_pdf}'
                return FileReadObservation(path=filepath, content=encoded_pdf)
            elif filepath.lower().endswith(('.mp4', '.webm', '.ogg')):
                with open(filepath, 'rb') as file:
                    video_data = file.read()
                    encoded_video = base64.b64encode(video_data).decode('utf-8')
                    mime_type, _ = mimetypes.guess_type(filepath)
                    if mime_type is None:
                        mime_type = 'video/mp4'  # default to MP4 if MIME type cannot be determined
                    encoded_video = f'data:{mime_type};base64,{encoded_video}'

                return FileReadObservation(path=filepath, content=encoded_video)

            with open(filepath, 'r', encoding='utf-8') as file:
                lines = read_lines(file.readlines(), action.start, action.end)
        except FileNotFoundError:
            return ErrorObservation(
                f'File not found: {filepath}. Your current working directory is {working_dir}.'
            )
        except UnicodeDecodeError:
            return ErrorObservation(f'File could not be decoded as utf-8: {filepath}.')
        except IsADirectoryError:
            return ErrorObservation(
                f'Path is a directory: {filepath}. You can only read files'
            )

        code_view = ''.join(lines)
        return FileReadObservation(path=filepath, content=code_view)

    async def write(self, action: FileWriteAction) -> Observation:
        working_dir = self.bash_session.workdir
        filepath = self._resolve_path(action.path, working_dir)

        insert = action.content.split('\n')
        try:
            if not os.path.exists(os.path.dirname(filepath)):
                os.makedirs(os.path.dirname(filepath))

            file_exists = os.path.exists(filepath)
            if file_exists:
                file_stat = os.stat(filepath)
            else:
                file_stat = None

            mode = 'w' if not file_exists else 'r+'
            try:
                with open(filepath, mode, encoding='utf-8') as file:
                    if mode != 'w':
                        all_lines = file.readlines()
                        new_file = insert_lines(
                            insert, all_lines, action.start, action.end
                        )
                    else:
                        new_file = [i + '\n' for i in insert]

                    file.seek(0)
                    file.writelines(new_file)
                    file.truncate()

                # Handle file permissions
                if file_exists:
                    assert file_stat is not None
                    # restore the original file permissions if the file already exists
                    os.chmod(filepath, file_stat.st_mode)
                    os.chown(filepath, file_stat.st_uid, file_stat.st_gid)
                else:
                    # set the new file permissions if the file is new
                    os.chmod(filepath, 0o664)
                    os.chown(filepath, self.user_id, self.user_id)

            except FileNotFoundError:
                return ErrorObservation(f'File not found: {filepath}')
            except IsADirectoryError:
                return ErrorObservation(
                    f'Path is a directory: {filepath}. You can only write to files'
                )
            except UnicodeDecodeError:
                return ErrorObservation(
                    f'File could not be decoded as utf-8: {filepath}'
                )
        except PermissionError:
            return ErrorObservation(f'Malformed paths not permitted: {filepath}')
        return FileWriteObservation(content='', path=filepath)

    async def browse(self, action: BrowseURLAction) -> Observation:
        return await browse(action, self.browser)

    async def browse_interactive(self, action: BrowseInteractiveAction) -> Observation:
        return await browse(action, self.browser)

    def close(self):
        self.bash_session.close()
        self.browser.close()


if __name__ == '__main__':
    parser = argparse.ArgumentParser()
    parser.add_argument('port', type=int, help='Port to listen on')
    parser.add_argument('--working-dir', type=str, help='Working directory')
    parser.add_argument('--plugins', type=str, help='Plugins to initialize', nargs='+')
    parser.add_argument(
        '--username', type=str, help='User to run as', default='openhands'
    )
    parser.add_argument('--user-id', type=int, help='User ID to run as', default=1000)
    parser.add_argument(
        '--browsergym-eval-env',
        type=str,
        help='BrowserGym environment used for browser evaluation',
        default=None,
    )
    # example: python client.py 8000 --working-dir /workspace --plugins JupyterRequirement
    args = parser.parse_args()
    os.environ['VSCODE_PORT'] = str(int(args.port) + 1)
    assert check_port_available(int(os.environ['VSCODE_PORT']))

    plugins_to_load: list[Plugin] = []
    if args.plugins:
        for plugin in args.plugins:
            if plugin not in ALL_PLUGINS:
                raise ValueError(f'Plugin {plugin} not found')
            plugins_to_load.append(ALL_PLUGINS[plugin]())  # type: ignore

    client: ActionExecutor | None = None

    @asynccontextmanager
    async def lifespan(app: FastAPI):
        global client
        client = ActionExecutor(
            plugins_to_load,
            work_dir=args.working_dir,
            username=args.username,
            user_id=args.user_id,
            browsergym_eval_env=args.browsergym_eval_env,
        )
        await client.ainit()
        yield
        # Clean up & release the resources
        client.close()

    app = FastAPI(lifespan=lifespan)

    # TODO below 3 exception handlers were recommended by Sonnet.
    # Are these something we should keep?
    @app.exception_handler(Exception)
    async def global_exception_handler(request: Request, exc: Exception):
        logger.exception('Unhandled exception occurred:')
        return JSONResponse(
            status_code=500,
            content={
                'message': 'An unexpected error occurred. Please try again later.'
            },
        )

    @app.exception_handler(StarletteHTTPException)
    async def http_exception_handler(request: Request, exc: StarletteHTTPException):
        logger.error(f'HTTP exception occurred: {exc.detail}')
        return JSONResponse(
            status_code=exc.status_code, content={'message': exc.detail}
        )

    @app.exception_handler(RequestValidationError)
    async def validation_exception_handler(
        request: Request, exc: RequestValidationError
    ):
        logger.error(f'Validation error occurred: {exc}')
        return JSONResponse(
            status_code=422,
            content={'message': 'Invalid request parameters', 'details': exc.errors()},
        )

    @app.middleware('http')
    async def authenticate_requests(request: Request, call_next):
        if request.url.path != '/alive' and request.url.path != '/server_info':
            try:
                verify_api_key(request.headers.get('X-Session-API-Key'))
            except HTTPException as e:
                return e
        response = await call_next(request)
        return response

    @app.get('/server_info')
    async def get_server_info():
        assert client is not None
        current_time = time.time()
        uptime = current_time - client.start_time
        idle_time = current_time - client.last_execution_time
        return {'uptime': uptime, 'idle_time': idle_time}

    @app.post('/execute_action')
    async def execute_action(action_request: ActionRequest):
        assert client is not None
        try:
            action = event_from_dict(action_request.action)
            if not isinstance(action, Action):
                raise HTTPException(status_code=400, detail='Invalid action type')
            client.last_execution_time = time.time()
            observation = await client.run_action(action)
            return event_to_dict(observation)
        except Exception as e:
            logger.error(
                f'Error processing command: {str(e)}', exc_info=True, stack_info=True
            )
            raise HTTPException(status_code=500, detail=str(e))

    @app.post('/upload_file')
    async def upload_file(
        file: UploadFile, destination: str = '/', recursive: bool = False
    ):
        assert client is not None

        try:
            # Ensure the destination directory exists
            if not os.path.isabs(destination):
                raise HTTPException(
                    status_code=400, detail='Destination must be an absolute path'
                )

            full_dest_path = destination
            if not os.path.exists(full_dest_path):
                os.makedirs(full_dest_path, exist_ok=True)

            if recursive or file.filename.endswith('.zip'):
                # For recursive uploads, we expect a zip file
                if not file.filename.endswith('.zip'):
                    raise HTTPException(
                        status_code=400, detail='Recursive uploads must be zip files'
                    )

                zip_path = os.path.join(full_dest_path, file.filename)
                with open(zip_path, 'wb') as buffer:
                    shutil.copyfileobj(file.file, buffer)

                # Extract the zip file
                shutil.unpack_archive(zip_path, full_dest_path)
                os.remove(zip_path)  # Remove the zip file after extraction

                logger.debug(
                    f'Uploaded file {file.filename} and extracted to {destination}'
                )
            else:
                # For single file uploads
                file_path = os.path.join(full_dest_path, file.filename)
                with open(file_path, 'wb') as buffer:
                    shutil.copyfileobj(file.file, buffer)
                logger.debug(f'Uploaded file {file.filename} to {destination}')

            return JSONResponse(
                content={
                    'filename': file.filename,
                    'destination': destination,
                    'recursive': recursive,
                },
                status_code=200,
            )

        except Exception as e:
            raise HTTPException(status_code=500, detail=str(e))

    @app.get('/download_files')
    async def download_file(path: str):
        logger.debug('Downloading files')
        try:
            if not os.path.isabs(path):
                raise HTTPException(
                    status_code=400, detail='Path must be an absolute path'
                )

            if not os.path.exists(path):
                raise HTTPException(status_code=404, detail='File not found')

            with tempfile.TemporaryFile() as temp_zip:
                with ZipFile(temp_zip, 'w') as zipf:
                    for root, _, files in os.walk(path):
                        for file in files:
                            file_path = os.path.join(root, file)
                            zipf.write(
                                file_path, arcname=os.path.relpath(file_path, path)
                            )
                temp_zip.seek(0)  # Rewind the file to the beginning after writing
                content = temp_zip.read()
                # Good for small to medium-sized files. For very large files, streaming directly from the
                # file chunks may be more memory-efficient.
                zip_stream = io.BytesIO(content)
                return StreamingResponse(
                    content=zip_stream,
                    media_type='application/zip',
                    headers={'Content-Disposition': f'attachment; filename={path}.zip'},
                )

        except Exception as e:
            raise HTTPException(status_code=500, detail=str(e))

    @app.get('/alive')
    async def alive():
        return {'status': 'ok'}

    # ================================
    # VSCode-specific operations
    # ================================

    @app.get('/vscode/connection_token')
    async def get_vscode_connection_token():
        assert client is not None
        if 'vscode' in client.plugins:
            plugin: VSCodePlugin = client.plugins['vscode']  # type: ignore
            return {'token': plugin.vscode_connection_token}
        else:
            return {'token': None}

    # ================================
    # File-specific operations for UI
    # ================================

    @app.post('/list_files')
    async def list_files(request: Request):
        """List files in the specified path.

        This function retrieves a list of files from the agent's runtime file store,
        excluding certain system and hidden files/directories.

        To list files:
        ```sh
        curl http://localhost:3000/api/list-files
        ```

        Args:
            request (Request): The incoming request object.
            path (str, optional): The path to list files from. Defaults to '/'.

        Returns:
            list: A list of file names in the specified path.

        Raises:
            HTTPException: If there's an error listing the files.
        """
        assert client is not None

        # get request as dict
        request_dict = await request.json()
        path = request_dict.get('path', None)

        # Get the full path of the requested directory
        if path is None:
            full_path = client.initial_pwd
        elif os.path.isabs(path):
            full_path = path
        else:
            full_path = os.path.join(client.initial_pwd, path)

        if not os.path.exists(full_path):
            # if user just removed a folder, prevent server error 500 in UI
            return []

        try:
            # Check if the directory exists
            if not os.path.exists(full_path) or not os.path.isdir(full_path):
                return []

            entries = os.listdir(full_path)

            # Separate directories and files
            directories = []
            files = []
            for entry in entries:
                # Remove leading slash and any parent directory components
                entry_relative = entry.lstrip('/').split('/')[-1]

                # Construct the full path by joining the base path with the relative entry path
                full_entry_path = os.path.join(full_path, entry_relative)
                if os.path.exists(full_entry_path):
                    is_dir = os.path.isdir(full_entry_path)
                    if is_dir:
                        # add trailing slash to directories
                        # required by FE to differentiate directories and files
                        entry = entry.rstrip('/') + '/'
                        directories.append(entry)
                    else:
                        files.append(entry)

            # Sort directories and files separately
            directories.sort(key=lambda s: s.lower())
            files.sort(key=lambda s: s.lower())

            # Combine sorted directories and files
            sorted_entries = directories + files
            return sorted_entries

        except Exception as e:
            logger.error(f'Error listing files: {e}', exc_info=True)
            return []

    logger.debug(f'Starting action execution API on port {args.port}')
    run(app, host='0.0.0.0', port=args.port)
