"""
Rules defined here:
https://confluence.atlassian.com/conf85/check-who-can-view-a-page-1283360557.html
"""
from typing import Any

from ee.onyx.configs.app_configs import CONFLUENCE_ANONYMOUS_ACCESS_IS_PUBLIC
from ee.onyx.external_permissions.confluence.constants import ALL_CONF_EMAILS_GROUP_NAME
from onyx.access.models import DocExternalAccess
from onyx.access.models import ExternalAccess
from onyx.connectors.confluence.connector import ConfluenceConnector
from onyx.connectors.confluence.onyx_confluence import (
    get_user_email_from_username__server,
)
from onyx.connectors.confluence.onyx_confluence import OnyxConfluence
from onyx.connectors.credentials_provider import OnyxDBCredentialsProvider
from onyx.connectors.models import SlimDocument
from onyx.db.models import ConnectorCredentialPair
from onyx.indexing.indexing_heartbeat import IndexingHeartbeatInterface
from onyx.utils.logger import setup_logger
from shared_configs.contextvars import get_current_tenant_id

logger = setup_logger()

_VIEWSPACE_PERMISSION_TYPE = "VIEWSPACE"
_REQUEST_PAGINATION_LIMIT = 5000


def _get_server_space_permissions(
    confluence_client: OnyxConfluence, space_key: str
) -> ExternalAccess:
    space_permissions = confluence_client.get_all_space_permissions_server(
        space_key=space_key
    )

    viewspace_permissions = []
    for permission_category in space_permissions:
        if permission_category.get("type") == _VIEWSPACE_PERMISSION_TYPE:
            viewspace_permissions.extend(
                permission_category.get("spacePermissions", [])
            )

    is_public = False
    user_names = set()
    group_names = set()
    for permission in viewspace_permissions:
        user_name = permission.get("userName")
        if user_name:
            user_names.add(user_name)
        group_name = permission.get("groupName")
        if group_name:
            group_names.add(group_name)

        # It seems that if anonymous access is turned on for the site and space,
        # then the space is publicly accessible.
        # For confluence server, we make a group that contains all users
        # that exist in confluence and then just add that group to the space permissions
        # if anonymous access is turned on for the site and space or we set is_public = True
        # if they set the env variable CONFLUENCE_ANONYMOUS_ACCESS_IS_PUBLIC to True so
        # that we can support confluence server deployments that want anonymous access
        # to be public (we cant test this because its paywalled)
        if user_name is None and group_name is None:
            # Defaults to False
            if CONFLUENCE_ANONYMOUS_ACCESS_IS_PUBLIC:
                is_public = True
            else:
                group_names.add(ALL_CONF_EMAILS_GROUP_NAME)

    user_emails = set()
    for user_name in user_names:
        user_email = get_user_email_from_username__server(confluence_client, user_name)
        if user_email:
            user_emails.add(user_email)
        else:
            logger.warning(f"Email for user {user_name} not found in Confluence")

    if not user_emails and not group_names:
        logger.warning(
            "No user emails or group names found in Confluence space permissions"
            f"\nSpace key: {space_key}"
            f"\nSpace permissions: {space_permissions}"
        )

    return ExternalAccess(
        external_user_emails=user_emails,
        external_user_group_ids=group_names,
        is_public=is_public,
    )


def _get_cloud_space_permissions(
    confluence_client: OnyxConfluence, space_key: str
) -> ExternalAccess:
    space_permissions_result = confluence_client.get_space(
        space_key=space_key, expand="permissions"
    )
    space_permissions = space_permissions_result.get("permissions", [])

    user_emails = set()
    group_names = set()
    is_externally_public = False
    for permission in space_permissions:
        subs = permission.get("subjects")
        if subs:
            # If there are subjects, then there are explicit users or groups with access
            if email := subs.get("user", {}).get("results", [{}])[0].get("email"):
                user_emails.add(email)
            if group_name := subs.get("group", {}).get("results", [{}])[0].get("name"):
                group_names.add(group_name)
        else:
            # If there are no subjects, then the permission is for everyone
            if permission.get("operation", {}).get(
                "operation"
            ) == "read" and permission.get("anonymousAccess", False):
                # If the permission specifies read access for anonymous users, then
                # the space is publicly accessible
                is_externally_public = True

    return ExternalAccess(
        external_user_emails=user_emails,
        external_user_group_ids=group_names,
        is_public=is_externally_public,
    )


def _get_space_permissions(
    confluence_client: OnyxConfluence,
    is_cloud: bool,
) -> dict[str, ExternalAccess]:
    logger.debug("Getting space permissions")
    # Gets all the spaces in the Confluence instance
    all_space_keys = []
    start = 0
    while True:
        spaces_batch = confluence_client.get_all_spaces(
            start=start, limit=_REQUEST_PAGINATION_LIMIT
        )
        for space in spaces_batch.get("results", []):
            all_space_keys.append(space.get("key"))

        if len(spaces_batch.get("results", [])) < _REQUEST_PAGINATION_LIMIT:
            break

        start += len(spaces_batch.get("results", []))

    # Gets the permissions for each space
    logger.debug(f"Got {len(all_space_keys)} spaces from confluence")
    space_permissions_by_space_key: dict[str, ExternalAccess] = {}
    for space_key in all_space_keys:
        if is_cloud:
            space_permissions = _get_cloud_space_permissions(
                confluence_client=confluence_client, space_key=space_key
            )
        else:
            space_permissions = _get_server_space_permissions(
                confluence_client=confluence_client, space_key=space_key
            )

        # Stores the permissions for each space
        space_permissions_by_space_key[space_key] = space_permissions

    return space_permissions_by_space_key


def _extract_read_access_restrictions(
    confluence_client: OnyxConfluence, restrictions: dict[str, Any]
) -> tuple[set[str], set[str]]:
    """
    Converts a page's restrictions dict into an ExternalAccess object.
    If there are no restrictions, then return None
    """
    read_access = restrictions.get("read", {})
    read_access_restrictions = read_access.get("restrictions", {})

    # Extract the users with read access
    read_access_user = read_access_restrictions.get("user", {})
    read_access_user_jsons = read_access_user.get("results", [])
    read_access_user_emails = []
    for user in read_access_user_jsons:
        # If the user has an email, then add it to the list
        if user.get("email"):
            read_access_user_emails.append(user["email"])
        # If the user has a username and not an email, then get the email from Confluence
        elif user.get("username"):
            email = get_user_email_from_username__server(
                confluence_client=confluence_client, user_name=user["username"]
            )
            if email:
                read_access_user_emails.append(email)
            else:
                logger.warning(
                    f"Email for user {user['username']} not found in Confluence"
                )
        else:
            if user.get("email") is not None:
                logger.warning(f"Cant find email for user {user.get('displayName')}")
                logger.warning(
                    "This user needs to make their email accessible in Confluence Settings"
                )

            logger.warning(f"no user email or username for {user}")

    # Extract the groups with read access
    read_access_group = read_access_restrictions.get("group", {})
    read_access_group_jsons = read_access_group.get("results", [])
    read_access_group_names = [
        group["name"] for group in read_access_group_jsons if group.get("name")
    ]

    return set(read_access_user_emails), set(read_access_group_names)


def _get_all_page_restrictions(
    confluence_client: OnyxConfluence,
    perm_sync_data: dict[str, Any],
) -> ExternalAccess | None:
    """
    This function gets the restrictions for a page by taking the intersection
    of the page's restrictions and the restrictions of all the ancestors
    of the page.
    If the page/ancestor has no restrictions, then it is ignored (no intersection).
    If no restrictions are found anywhere, then return None, indicating that the page
    should inherit the space's restrictions.
    """
    found_user_emails: set[str] = set()
    found_group_names: set[str] = set()

    found_user_emails, found_group_names = _extract_read_access_restrictions(
        confluence_client=confluence_client,
        restrictions=perm_sync_data.get("restrictions", {}),
    )

    ancestors: list[dict[str, Any]] = perm_sync_data.get("ancestors", [])
    for ancestor in ancestors:
        ancestor_user_emails, ancestor_group_names = _extract_read_access_restrictions(
            confluence_client=confluence_client,
            restrictions=ancestor.get("restrictions", {}),
        )
        if not ancestor_user_emails and not ancestor_group_names:
            # This ancestor has no restrictions, so it has no effect on
            # the page's restrictions, so we ignore it
            continue

        found_user_emails.intersection_update(ancestor_user_emails)
        found_group_names.intersection_update(ancestor_group_names)

    # If there are no restrictions found, then the page
    # inherits the space's restrictions so return None
    if not found_user_emails and not found_group_names:
        return None

    return ExternalAccess(
        external_user_emails=found_user_emails,
        external_user_group_ids=found_group_names,
        # there is no way for a page to be individually public if the space isn't public
        is_public=False,
    )


def _fetch_all_page_restrictions(
    confluence_client: OnyxConfluence,
    slim_docs: list[SlimDocument],
    space_permissions_by_space_key: dict[str, ExternalAccess],
    is_cloud: bool,
    callback: IndexingHeartbeatInterface | None,
) -> list[DocExternalAccess]:
    """
    For all pages, if a page has restrictions, then use those restrictions.
    Otherwise, use the space's restrictions.
    """
    document_restrictions: list[DocExternalAccess] = []

    for slim_doc in slim_docs:
        if callback:
            if callback.should_stop():
                raise RuntimeError("confluence_doc_sync: Stop signal detected")

            callback.progress("confluence_doc_sync:fetch_all_page_restrictions", 1)

        if slim_doc.perm_sync_data is None:
            raise ValueError(
                f"No permission sync data found for document {slim_doc.id}"
            )

        if restrictions := _get_all_page_restrictions(
            confluence_client=confluence_client,
            perm_sync_data=slim_doc.perm_sync_data,
        ):
            document_restrictions.append(
                DocExternalAccess(
                    doc_id=slim_doc.id,
                    external_access=restrictions,
                )
            )
            # If there are restrictions, then we don't need to use the space's restrictions
            continue

        space_key = slim_doc.perm_sync_data.get("space_key")
        if not (space_permissions := space_permissions_by_space_key.get(space_key)):
            logger.debug(
                f"Individually fetching space permissions for space {space_key}"
            )
            try:
                # If the space permissions are not in the cache, then fetch them
                if is_cloud:
                    retrieved_space_permissions = _get_cloud_space_permissions(
                        confluence_client=confluence_client, space_key=space_key
                    )
                else:
                    retrieved_space_permissions = _get_server_space_permissions(
                        confluence_client=confluence_client, space_key=space_key
                    )
                space_permissions_by_space_key[space_key] = retrieved_space_permissions
                space_permissions = retrieved_space_permissions
            except Exception as e:
                logger.warning(
                    f"Error fetching space permissions for space {space_key}: {e}"
                )

        if not space_permissions:
            logger.warning(
                f"No permissions found for document {slim_doc.id} in space {space_key}"
            )
            continue

        # If there are no restrictions, then use the space's restrictions
        document_restrictions.append(
            DocExternalAccess(
                doc_id=slim_doc.id,
                external_access=space_permissions,
            )
        )
        if (
            not space_permissions.is_public
            and not space_permissions.external_user_emails
            and not space_permissions.external_user_group_ids
        ):
            logger.warning(
                f"Permissions are empty for document: {slim_doc.id}\n"
                "This means space permissions are may be wrong for"
                f" Space key: {space_key}"
            )

    logger.debug("Finished fetching all page restrictions for space")
    return document_restrictions


def confluence_doc_sync(
    cc_pair: ConnectorCredentialPair,
    callback: IndexingHeartbeatInterface | None,
) -> list[DocExternalAccess]:
    """
    Adds the external permissions to the documents in postgres
    if the document doesn't already exists in postgres, we create
    it in postgres so that when it gets created later, the permissions are
    already populated
    """
    logger.debug("Starting confluence doc sync")
    confluence_connector = ConfluenceConnector(
        **cc_pair.connector.connector_specific_config
    )

    provider = OnyxDBCredentialsProvider(
        get_current_tenant_id(), "confluence", cc_pair.credential_id
    )
    confluence_connector.set_credentials_provider(provider)

    is_cloud = cc_pair.connector.connector_specific_config.get("is_cloud", False)

    space_permissions_by_space_key = _get_space_permissions(
        confluence_client=confluence_connector.confluence_client,
        is_cloud=is_cloud,
    )

    slim_docs = []
    logger.debug("Fetching all slim documents from confluence")
    for doc_batch in confluence_connector.retrieve_all_slim_documents(
        callback=callback
    ):
        logger.debug(f"Got {len(doc_batch)} slim documents from confluence")
        if callback:
            if callback.should_stop():
                raise RuntimeError("confluence_doc_sync: Stop signal detected")

            callback.progress("confluence_doc_sync", 1)

        slim_docs.extend(doc_batch)

    logger.debug("Fetching all page restrictions for space")
    return _fetch_all_page_restrictions(
        confluence_client=confluence_connector.confluence_client,
        slim_docs=slim_docs,
        space_permissions_by_space_key=space_permissions_by_space_key,
        is_cloud=is_cloud,
        callback=callback,
    )