"""PDPL data subject rights handler.
Right to access, correction, deletion, restriction + SDAIA compliance reports.
"""
import logging
from datetime import datetime, timedelta, timezone
from typing import Any, Optional
from uuid import UUID

from pydantic import BaseModel as Schema
from sqlalchemy import select, func
from sqlalchemy.ext.asyncio import AsyncSession

from app.models.consent import PDPLConsent, DataRequest, DataRequestStatus, DataRequestType
from app.models.lead import Lead
from app.models.message import Message

logger = logging.getLogger(__name__)
HARD_DELETE_DELAY_DAYS = 30


class DataExport(Schema):
    contact_id: UUID
    personal_data: dict
    consents: list[dict]
    messages: list[dict]
    exported_at: datetime


class CorrectionInput(Schema):
    contact_id: UUID
    tenant_id: UUID
    corrections: dict[str, Any]
    actor_id: Optional[UUID] = None
    reason: Optional[str] = None


class CorrectionResult(Schema):
    contact_id: UUID
    fields_updated: list[str]
    previous_values: dict
    updated_at: datetime


class DeletionResult(Schema):
    contact_id: UUID
    status: str
    soft_deleted_at: datetime
    hard_delete_scheduled: datetime
    message: str
    message_ar: str


class RestrictionResult(Schema):
    contact_id: UUID
    restricted: bool
    message: str
    message_ar: str


class ComplianceReport(Schema):
    tenant_id: UUID
    generated_at: datetime
    total_consents: int
    active_consents: int
    revoked_consents: int
    expired_consents: int
    pending_requests: int
    completed_requests: int
    requests_by_type: dict[str, int]
    avg_resolution_hours: Optional[float] = None
    violations_detected: int


class DataRightsHandler:
    """Handles PDPL data subject rights for Dealix contacts."""

    def __init__(self, db: AsyncSession):
        self.db = db

    async def export_data(self, contact_id: UUID, tenant_id: UUID) -> DataExport:
        """Export all personal data held for a contact (right to access)."""
        lead = await self._get_lead(contact_id, tenant_id)
        consents_q = await self.db.execute(
            select(PDPLConsent).where(PDPLConsent.contact_id == contact_id, PDPLConsent.tenant_id == tenant_id)
        )
        consents = [
            {"purpose": c.purpose, "channel": c.channel, "status": c.status,
             "granted_at": c.granted_at.isoformat() if c.granted_at else None,
             "expires_at": c.expires_at.isoformat() if c.expires_at else None}
            for c in consents_q.scalars().all()
        ]
        msgs_q = await self.db.execute(select(Message).where(Message.lead_id == contact_id).limit(500))
        messages = [
            {"channel": m.channel, "direction": m.direction, "content": m.content,
             "sent_at": m.sent_at.isoformat() if m.sent_at else None}
            for m in msgs_q.scalars().all()
        ]
        logger.info("PDPL data export: contact=%s", contact_id)
        return DataExport(
            contact_id=contact_id,
            personal_data={"name": lead.name, "phone": lead.phone, "email": lead.email,
                           "source": lead.source, "status": lead.status, "score": lead.score, "notes": lead.notes},
            consents=consents, messages=messages, exported_at=datetime.now(timezone.utc),
        )

    async def correct_data(self, data: CorrectionInput) -> CorrectionResult:
        """Update personal data fields with audit trail."""
        lead = await self._get_lead(data.contact_id, data.tenant_id)
        allowed_fields = {"name", "phone", "email", "notes"}
        previous: dict[str, Any] = {}
        updated: list[str] = []
        for field, new_val in data.corrections.items():
            if field not in allowed_fields:
                logger.warning("PDPL correction rejected for field=%s", field)
                continue
            previous[field] = getattr(lead, field, None)
            setattr(lead, field, new_val)
            updated.append(field)
        await self.db.flush()
        self.db.add(DataRequest(
            contact_id=data.contact_id, tenant_id=data.tenant_id,
            request_type=DataRequestType.CORRECTION.value, status=DataRequestStatus.COMPLETED.value,
            requested_at=datetime.now(timezone.utc), completed_at=datetime.now(timezone.utc),
            response_data={"corrections": data.corrections, "previous": previous}, handled_by=data.actor_id,
        ))
        await self.db.flush()
        logger.info("PDPL correction: contact=%s fields=%s", data.contact_id, updated)
        return CorrectionResult(contact_id=data.contact_id, fields_updated=updated,
                                previous_values=previous, updated_at=datetime.now(timezone.utc))

    async def delete_data(self, contact_id: UUID, tenant_id: UUID,
                          actor_id: Optional[UUID] = None) -> DeletionResult:
        """Soft-delete contact; schedule hard-delete after 30 days."""
        lead = await self._get_lead(contact_id, tenant_id)
        now = datetime.now(timezone.utc)
        hard_at = now + timedelta(days=HARD_DELETE_DELAY_DAYS)
        lead.status = "deleted"
        lead.notes = f"[PDPL deletion {now.isoformat()}] " + (lead.notes or "")
        lead.extra_metadata = {**(lead.extra_metadata or {}),
                               "_pdpl_soft_deleted": True, "_pdpl_hard_delete_at": hard_at.isoformat()}
        # Revoke active consents
        cq = await self.db.execute(
            select(PDPLConsent).where(PDPLConsent.contact_id == contact_id,
                                      PDPLConsent.tenant_id == tenant_id, PDPLConsent.status == "granted")
        )
        for c in cq.scalars().all():
            c.status = "revoked"
            c.revoked_at = now
        self.db.add(DataRequest(
            contact_id=contact_id, tenant_id=tenant_id,
            request_type=DataRequestType.DELETION.value, status=DataRequestStatus.PROCESSING.value,
            requested_at=now, response_data={"hard_delete_at": hard_at.isoformat()}, handled_by=actor_id,
        ))
        await self.db.flush()
        logger.info("PDPL deletion: contact=%s hard_delete=%s", contact_id, hard_at)
        return DeletionResult(
            contact_id=contact_id, status="soft_deleted", soft_deleted_at=now,
            hard_delete_scheduled=hard_at,
            message=f"Hard delete scheduled for {hard_at.date()}",
            message_ar=f"الحذف النهائي مجدول بتاريخ {hard_at.date()}",
        )

    async def restrict_processing(self, contact_id: UUID, tenant_id: UUID,
                                  actor_id: Optional[UUID] = None) -> RestrictionResult:
        """Flag contact as restricted -- no outbound processing allowed."""
        lead = await self._get_lead(contact_id, tenant_id)
        lead.extra_metadata = {**(lead.extra_metadata or {}),
                               "_pdpl_restricted": True,
                               "_pdpl_restricted_at": datetime.now(timezone.utc).isoformat()}
        self.db.add(DataRequest(
            contact_id=contact_id, tenant_id=tenant_id,
            request_type=DataRequestType.RESTRICTION.value, status=DataRequestStatus.COMPLETED.value,
            requested_at=datetime.now(timezone.utc), completed_at=datetime.now(timezone.utc),
            response_data={"restricted": True}, handled_by=actor_id,
        ))
        await self.db.flush()
        logger.info("PDPL restriction: contact=%s", contact_id)
        return RestrictionResult(
            contact_id=contact_id, restricted=True,
            message="Contact processing restricted per PDPL",
            message_ar="تم تقييد معالجة بيانات جهة الاتصال وفقًا لنظام حماية البيانات",
        )

    async def generate_compliance_report(self, tenant_id: UUID) -> ComplianceReport:
        """Generate SDAIA-ready compliance report."""
        now = datetime.now(timezone.utc)
        total = (await self.db.execute(
            select(func.count()).where(PDPLConsent.tenant_id == tenant_id))).scalar() or 0
        active = (await self.db.execute(
            select(func.count()).where(PDPLConsent.tenant_id == tenant_id, PDPLConsent.status == "granted"))).scalar() or 0
        revoked = (await self.db.execute(
            select(func.count()).where(PDPLConsent.tenant_id == tenant_id, PDPLConsent.status == "revoked"))).scalar() or 0
        expired = (await self.db.execute(
            select(func.count()).where(PDPLConsent.tenant_id == tenant_id, PDPLConsent.status == "expired"))).scalar() or 0
        pending = (await self.db.execute(
            select(func.count()).where(DataRequest.tenant_id == tenant_id, DataRequest.status == "pending"))).scalar() or 0
        completed = (await self.db.execute(
            select(func.count()).where(DataRequest.tenant_id == tenant_id, DataRequest.status == "completed"))).scalar() or 0
        type_rows = (await self.db.execute(
            select(DataRequest.request_type, func.count()).where(DataRequest.tenant_id == tenant_id)
            .group_by(DataRequest.request_type))).all()
        by_type = {r[0]: r[1] for r in type_rows}
        # Average resolution time
        avg_hours: Optional[float] = None
        done = (await self.db.execute(
            select(DataRequest).where(DataRequest.tenant_id == tenant_id, DataRequest.status == "completed",
                                      DataRequest.completed_at.isnot(None)).limit(500))).scalars().all()
        if done:
            deltas = [(r.completed_at - r.requested_at).total_seconds() / 3600
                      for r in done if r.completed_at and r.requested_at]
            avg_hours = round(sum(deltas) / len(deltas), 2) if deltas else None
        logger.info("PDPL report generated: tenant=%s", tenant_id)
        return ComplianceReport(
            tenant_id=tenant_id, generated_at=now, total_consents=total,
            active_consents=active, revoked_consents=revoked, expired_consents=expired,
            pending_requests=pending, completed_requests=completed,
            requests_by_type=by_type, avg_resolution_hours=avg_hours, violations_detected=0,
        )

    async def _get_lead(self, contact_id: UUID, tenant_id: UUID) -> Lead:
        result = await self.db.execute(
            select(Lead).where(Lead.id == contact_id, Lead.tenant_id == tenant_id))
        lead = result.scalar_one_or_none()
        if not lead:
            raise ValueError("جهة الاتصال غير موجودة")
        return lead