"""
FastAPI routes for DSFA — Datenschutz-Folgenabschaetzung (Art. 35 DSGVO).

Endpoints:
  GET    /v1/dsfa                            — Liste (tenant_id + status-filter + skip/limit)
  POST   /v1/dsfa                            — Neu erstellen -> 201
  GET    /v1/dsfa/stats                      — Zaehler nach Status
  GET    /v1/dsfa/audit-log                  — Audit-Log
  GET    /v1/dsfa/export/csv                 — CSV-Export aller DSFAs
  POST   /v1/dsfa/from-assessment/{id}       — Stub: DSFA aus UCCA-Assessment
  GET    /v1/dsfa/by-assessment/{id}         — Stub: DSFA nach Assessment-ID
  GET    /v1/dsfa/{id}                       — Detail
  PUT    /v1/dsfa/{id}                       — Update
  DELETE /v1/dsfa/{id}                       — Loeschen (Art. 17 DSGVO)
  PATCH  /v1/dsfa/{id}/status                — Schnell-Statuswechsel
  PUT    /v1/dsfa/{id}/sections/{nr}         — Section-Update (1-8)
  POST   /v1/dsfa/{id}/submit-for-review     — Workflow: Einreichen
  POST   /v1/dsfa/{id}/approve               — Workflow: Genehmigen/Ablehnen
  GET    /v1/dsfa/{id}/export                — JSON-Export einer DSFA

Phase 1 Step 4 refactor: handlers delegate to DSFAService (CRUD/stats/
audit/csv) and DSFAWorkflowService (status/section/submit/approve/export/
versions). Module-level helpers re-exported for legacy tests.
"""

import logging
from typing import Any, Optional

from fastapi import APIRouter, Depends, Query
from fastapi.responses import Response
from sqlalchemy.orm import Session

from classroom_engine.database import get_db
from compliance.api._http_errors import translate_domain_errors
from compliance.schemas.dsfa import (
    DSFAApproveRequest,
    DSFACreate,
    DSFASectionUpdate,
    DSFAStatusUpdate,
    DSFAUpdate,
)
from compliance.services.dsfa_service import (
    DEFAULT_TENANT_ID,
    VALID_RISK_LEVELS,
    VALID_STATUSES,
    DSFAService,
    _dsfa_to_response,  # re-exported for legacy test imports
    _get_tenant_id,  # re-exported for legacy test imports
)
from compliance.services.dsfa_workflow_service import (
    SECTION_FIELD_MAP,  # noqa: F401 — re-export
    DSFAWorkflowService,
)

logger = logging.getLogger(__name__)
router = APIRouter(prefix="/dsfa", tags=["compliance-dsfa"])


def get_dsfa_service(db: Session = Depends(get_db)) -> DSFAService:
    return DSFAService(db)


def get_workflow_service(
    db: Session = Depends(get_db),
) -> DSFAWorkflowService:
    return DSFAWorkflowService(db)


# =============================================================================
# Stats (must be before /{id} to avoid route conflict)
# =============================================================================


@router.get("/stats")
async def get_stats(
    tenant_id: Optional[str] = Query(None),
    service: DSFAService = Depends(get_dsfa_service),
) -> dict[str, Any]:
    """Zaehler nach Status und Risiko-Level."""
    with translate_domain_errors():
        return service.stats(tenant_id)


# =============================================================================
# Audit Log (must be before /{id} to avoid route conflict)
# =============================================================================


@router.get("/audit-log")
async def get_audit_log(
    tenant_id: Optional[str] = Query(None),
    limit: int = Query(50, ge=1, le=500),
    offset: int = Query(0, ge=0),
    service: DSFAService = Depends(get_dsfa_service),
) -> list[dict[str, Any]]:
    """DSFA Audit-Trail."""
    with translate_domain_errors():
        return service.audit_log(tenant_id, limit, offset)


# =============================================================================
# CSV Export (must be before /{id} to avoid route conflict)
# =============================================================================


@router.get("/export/csv", name="export_dsfas_csv")
async def export_dsfas_csv(
    tenant_id: Optional[str] = Query(None),
    service: DSFAService = Depends(get_dsfa_service),
) -> Response:
    """Export all DSFAs as CSV."""
    with translate_domain_errors():
        csv_content = service.export_csv(tenant_id)
    return Response(
        content=csv_content,
        media_type="text/csv",
        headers={
            "Content-Disposition": "attachment; filename=dsfas_export.csv"
        },
    )


# =============================================================================
# UCCA Integration Stubs (must be before /{id} to avoid route conflict)
# =============================================================================


@router.post("/from-assessment/{assessment_id}", status_code=501)
async def create_from_assessment(
    assessment_id: str,
) -> dict[str, str]:
    """Stub: Create DSFA from UCCA assessment."""
    return {
        "detail": (
            "Not implemented — requires cross-service "
            "integration with ai-compliance-sdk"
        )
    }


@router.get("/by-assessment/{assessment_id}", status_code=501)
async def get_by_assessment(
    assessment_id: str,
) -> dict[str, str]:
    """Stub: Get DSFA by linked UCCA assessment ID."""
    return {
        "detail": (
            "Not implemented — requires cross-service "
            "integration with ai-compliance-sdk"
        )
    }


# =============================================================================
# List + Create
# =============================================================================


@router.get("")
async def list_dsfas(
    tenant_id: Optional[str] = Query(None),
    status: Optional[str] = Query(None),
    risk_level: Optional[str] = Query(None),
    skip: int = Query(0, ge=0),
    limit: int = Query(100, ge=1, le=500),
    service: DSFAService = Depends(get_dsfa_service),
) -> list[dict[str, Any]]:
    """Liste aller DSFAs fuer einen Tenant."""
    with translate_domain_errors():
        return service.list_dsfas(tenant_id, status, risk_level, skip, limit)


@router.post("", status_code=201)
async def create_dsfa(
    request: DSFACreate,
    tenant_id: Optional[str] = Query(None),
    service: DSFAService = Depends(get_dsfa_service),
) -> dict[str, Any]:
    """Neue DSFA erstellen."""
    with translate_domain_errors():
        return service.create(tenant_id, request)


# =============================================================================
# Single Item (GET / PUT / DELETE / PATCH status)
# =============================================================================


@router.get("/{dsfa_id}")
async def get_dsfa(
    dsfa_id: str,
    tenant_id: Optional[str] = Query(None),
    service: DSFAService = Depends(get_dsfa_service),
) -> dict[str, Any]:
    """Einzelne DSFA abrufen."""
    with translate_domain_errors():
        return service.get(dsfa_id, tenant_id)


@router.put("/{dsfa_id}")
async def update_dsfa(
    dsfa_id: str,
    request: DSFAUpdate,
    tenant_id: Optional[str] = Query(None),
    service: DSFAService = Depends(get_dsfa_service),
) -> dict[str, Any]:
    """DSFA aktualisieren."""
    with translate_domain_errors():
        return service.update(dsfa_id, tenant_id, request)


@router.delete("/{dsfa_id}")
async def delete_dsfa(
    dsfa_id: str,
    tenant_id: Optional[str] = Query(None),
    service: DSFAService = Depends(get_dsfa_service),
) -> dict[str, Any]:
    """DSFA loeschen (Art. 17 DSGVO)."""
    with translate_domain_errors():
        return service.delete(dsfa_id, tenant_id)


@router.patch("/{dsfa_id}/status")
async def update_dsfa_status(
    dsfa_id: str,
    request: DSFAStatusUpdate,
    tenant_id: Optional[str] = Query(None),
    wf: DSFAWorkflowService = Depends(get_workflow_service),
) -> dict[str, Any]:
    """Schnell-Statuswechsel."""
    with translate_domain_errors():
        return wf.update_status(dsfa_id, tenant_id, request)


# =============================================================================
# Section Update
# =============================================================================


@router.put("/{dsfa_id}/sections/{section_number}")
async def update_section(
    dsfa_id: str,
    section_number: int,
    request: DSFASectionUpdate,
    tenant_id: Optional[str] = Query(None),
    wf: DSFAWorkflowService = Depends(get_workflow_service),
) -> dict[str, Any]:
    """Update a specific DSFA section (1-8)."""
    with translate_domain_errors():
        return wf.update_section(dsfa_id, section_number, tenant_id, request)


# =============================================================================
# Workflow: Submit for Review + Approve
# =============================================================================


@router.post("/{dsfa_id}/submit-for-review")
async def submit_for_review(
    dsfa_id: str,
    tenant_id: Optional[str] = Query(None),
    wf: DSFAWorkflowService = Depends(get_workflow_service),
) -> dict[str, Any]:
    """Submit a DSFA for DPO review (draft -> in-review)."""
    with translate_domain_errors():
        return wf.submit_for_review(dsfa_id, tenant_id)


@router.post("/{dsfa_id}/approve")
async def approve_dsfa(
    dsfa_id: str,
    request: DSFAApproveRequest,
    tenant_id: Optional[str] = Query(None),
    wf: DSFAWorkflowService = Depends(get_workflow_service),
) -> dict[str, Any]:
    """Approve or reject a DSFA (DPO/CISO action)."""
    with translate_domain_errors():
        return wf.approve(dsfa_id, tenant_id, request)


# =============================================================================
# Export
# =============================================================================


@router.get("/{dsfa_id}/export")
async def export_dsfa_json(
    dsfa_id: str,
    format: str = Query("json"),
    tenant_id: Optional[str] = Query(None),
    wf: DSFAWorkflowService = Depends(get_workflow_service),
) -> dict[str, Any]:
    """Export a single DSFA as JSON."""
    with translate_domain_errors():
        return wf.export_json(dsfa_id, tenant_id, format)


# =============================================================================
# Versioning
# =============================================================================


@router.get("/{dsfa_id}/versions")
async def list_dsfa_versions(
    dsfa_id: str,
    tenant_id: Optional[str] = Query(None),
    wf: DSFAWorkflowService = Depends(get_workflow_service),
) -> Any:
    """List all versions for a DSFA."""
    with translate_domain_errors():
        return wf.list_versions(dsfa_id, tenant_id)


@router.get("/{dsfa_id}/versions/{version_number}")
async def get_dsfa_version(
    dsfa_id: str,
    version_number: int,
    tenant_id: Optional[str] = Query(None),
    wf: DSFAWorkflowService = Depends(get_workflow_service),
) -> Any:
    """Get a specific DSFA version with full snapshot."""
    with translate_domain_errors():
        return wf.get_version(dsfa_id, version_number, tenant_id)


# Legacy re-exports
__all__ = [
    "router",
    "DSFACreate",
    "DSFAUpdate",
    "DSFAStatusUpdate",
    "DSFASectionUpdate",
    "DSFAApproveRequest",
    "_dsfa_to_response",
    "_get_tenant_id",
    "DEFAULT_TENANT_ID",
    "VALID_STATUSES",
    "VALID_RISK_LEVELS",
]