"""Workflow-configuration policies shared by workflow update surfaces."""

from __future__ import annotations

from copy import deepcopy
from typing import Any

from api.db import db_client
from api.services.organization_preferences import external_pbx_integrations_enabled

# Configuration keys owned by the External PBX UI section. All of them vanish
# from the request payload while that section is hidden, so all of them must be
# preserved from storage rather than silently reset to their defaults.
_EXTERNAL_PBX_CONFIGURATION_KEYS = (
    "external_pbx_field_mappings",
    "external_pbx_lead_headers",
)


class WorkflowConfigurationNotFoundError(LookupError):
    """Raised when configuration policy cannot resolve the target workflow."""


class ExternalPBXConfigurationDisabledError(PermissionError):
    """Raised when a disabled organization changes external-PBX mappings."""


async def apply_external_pbx_mapping_policy(
    workflow_configurations: dict[str, Any] | None,
    *,
    workflow_id: int,
    organization_id: int,
) -> dict[str, Any] | None:
    """Preserve hidden settings and reject edits while external PBX is disabled.

    Workflow configuration updates replace the stored configuration document. When
    the External PBX UI is hidden, its settings are absent from the request, so
    they must be copied from the active draft or published definition before the
    update is persisted.
    """
    if workflow_configurations is None or await external_pbx_integrations_enabled(
        organization_id
    ):
        return workflow_configurations

    workflow = await db_client.get_workflow(
        workflow_id, organization_id=organization_id
    )
    if workflow is None:
        raise WorkflowConfigurationNotFoundError(
            f"Workflow with id {workflow_id} not found"
        )

    draft = await db_client.get_draft_version(workflow_id)
    stored_configurations = (
        draft.workflow_configurations
        if draft
        else workflow.released_definition.workflow_configurations
    )
    prepared_configurations = dict(workflow_configurations)
    preserved_any = False
    for key in _EXTERNAL_PBX_CONFIGURATION_KEYS:
        stored_value = (stored_configurations or {}).get(key, [])
        incoming_value = workflow_configurations.get(key, stored_value)

        if incoming_value != stored_value:
            raise ExternalPBXConfigurationDisabledError(
                "External PBX integrations are disabled for this organization. "
                "Enable them in Platform Settings before changing external PBX "
                "settings."
            )

        if stored_value:
            prepared_configurations[key] = deepcopy(stored_value)
            preserved_any = True

    if not preserved_any:
        return workflow_configurations
    return prepared_configurations