import os
import re
from typing import Annotated

from fastmcp import FastMCP
from fastmcp.exceptions import ToolError
from fastmcp.server.dependencies import get_http_request
from pydantic import Field

from openhands.core.logger import openhands_logger as logger
from openhands.integrations.github.github_service import GithubServiceImpl
from openhands.integrations.gitlab.gitlab_service import GitLabServiceImpl
from openhands.integrations.provider import ProviderToken
from openhands.integrations.service_types import GitService, ProviderType
from openhands.server.dependencies import get_dependencies
from openhands.server.shared import ConversationStoreImpl, config, server_config
from openhands.server.types import AppMode
from openhands.server.user_auth import (
    get_access_token,
    get_provider_tokens,
    get_user_id,
)
from openhands.storage.data_models.conversation_metadata import ConversationMetadata

mcp_server = FastMCP(
    'mcp', stateless_http=True, dependencies=get_dependencies(), mask_error_details=True
)

HOST = f'https://{os.getenv("WEB_HOST", "app.all-hands.dev").strip()}'
CONVO_URL = HOST + '/{}'


async def get_convo_link(service: GitService, conversation_id: str, body: str) -> str:
    """
    Appends a followup link, in the PR body, to the OpenHands conversation that opened the PR
    """

    if server_config.app_mode != AppMode.SAAS:
        return body

    user = await service.get_user()
    username = user.login
    convo_url = CONVO_URL.format(conversation_id)
    convo_link = (
        f'@{username} can click here to [continue refining the PR]({convo_url})'
    )
    body += f'\n\n{convo_link}'
    return body


async def save_pr_metadata(
    user_id: str | None, conversation_id: str, tool_result: str
) -> None:
    conversation_store = await ConversationStoreImpl.get_instance(config, user_id)
    conversation: ConversationMetadata = await conversation_store.get_metadata(
        conversation_id
    )

    pull_pattern = r'pull/(\d+)'
    merge_request_pattern = r'merge_requests/(\d+)'

    # Check if the tool_result contains the PR number
    pr_number = None
    match_pull = re.search(pull_pattern, tool_result)
    match_merge_request = re.search(merge_request_pattern, tool_result)

    if match_pull:
        pr_number = int(match_pull.group(1))
    elif match_merge_request:
        pr_number = int(match_merge_request.group(1))

    if pr_number:
        logger.info(f'Saving PR number: {pr_number} for convo {conversation_id}')
        conversation.pr_number.append(pr_number)
    else:
        logger.warning(f'Failed to extract PR number for convo {conversation_id}')

    await conversation_store.save_metadata(conversation)


@mcp_server.tool()
async def create_pr(
    repo_name: Annotated[
        str, Field(description='GitHub repository ({{owner}}/{{repo}})')
    ],
    source_branch: Annotated[str, Field(description='Source branch on repo')],
    target_branch: Annotated[str, Field(description='Target branch on repo')],
    title: Annotated[str, Field(description='PR Title')],
    body: Annotated[str | None, Field(description='PR body')],
) -> str:
    """Open a PR in GitHub"""

    logger.info('Calling OpenHands MCP create_pr')

    request = get_http_request()
    headers = request.headers
    conversation_id = headers.get('X-OpenHands-ServerConversation-ID', None)

    provider_tokens = await get_provider_tokens(request)
    access_token = await get_access_token(request)
    user_id = await get_user_id(request)

    github_token = (
        provider_tokens.get(ProviderType.GITHUB, ProviderToken())
        if provider_tokens
        else ProviderToken()
    )

    github_service = GithubServiceImpl(
        user_id=github_token.user_id,
        external_auth_id=user_id,
        external_auth_token=access_token,
        token=github_token.token,
        base_domain=github_token.host,
    )

    try:
        body = await get_convo_link(github_service, conversation_id, body or '')
    except Exception as e:
        logger.warning(f'Failed to append convo link: {e}')

    try:
        response = await github_service.create_pr(
            repo_name=repo_name,
            source_branch=source_branch,
            target_branch=target_branch,
            title=title,
            body=body,
        )

        if conversation_id:
            await save_pr_metadata(user_id, conversation_id, response)

    except Exception as e:
        error = f'Error creating pull request: {e}'
        raise ToolError(str(error))

    return response


@mcp_server.tool()
async def create_mr(
    id: Annotated[
        int | str,
        Field(description='GitLab repository (ID or URL-encoded path of the project)'),
    ],
    source_branch: Annotated[str, Field(description='Source branch on repo')],
    target_branch: Annotated[str, Field(description='Target branch on repo')],
    title: Annotated[str, Field(description='MR Title')],
    description: Annotated[str | None, Field(description='MR description')],
) -> str:
    """Open a MR in GitLab"""

    logger.info('Calling OpenHands MCP create_mr')

    request = get_http_request()
    headers = request.headers
    conversation_id = headers.get('X-OpenHands-ServerConversation-ID', None)

    provider_tokens = await get_provider_tokens(request)
    access_token = await get_access_token(request)
    user_id = await get_user_id(request)

    github_token = (
        provider_tokens.get(ProviderType.GITLAB, ProviderToken())
        if provider_tokens
        else ProviderToken()
    )

    gitlab_service = GitLabServiceImpl(
        user_id=github_token.user_id,
        external_auth_id=user_id,
        external_auth_token=access_token,
        token=github_token.token,
        base_domain=github_token.host,
    )

    try:
        description = await get_convo_link(
            gitlab_service, conversation_id, description or ''
        )
    except Exception as e:
        logger.warning(f'Failed to append convo link: {e}')

    try:
        response = await gitlab_service.create_mr(
            id=id,
            source_branch=source_branch,
            target_branch=target_branch,
            title=title,
            description=description,
        )

        if conversation_id and user_id:
            await save_pr_metadata(user_id, conversation_id, response)

    except Exception as e:
        error = f'Error creating merge request: {e}'
        raise ToolError(str(error))

    return response