"""Public contract for the contacts plugin.

Exposes the symbols that other core modules and plugins need without
importing from internal modules directly (Block C7: dashboard counts).
"""

from __future__ import annotations

from typing import Any

from sqlalchemy import func, select
from sqlalchemy.ext.asyncio import AsyncSession

from app.core.visibility import apply_visibility_filter
from app.models.contact import Contact
from app.plugins.builtins.contracts import get_contract_registry


class ContactsContract:
    """Public API surface for the contacts plugin."""

    contract_name = "contacts"

    @staticmethod
    async def get_counts(
        db: AsyncSession,
        tenant_id: Any,
        user_id: Any,
        is_system_admin: bool = False,
    ) -> dict[str, int]:
        """Return visibility-filtered contact/company/person counts."""
        queries = []
        for type_filter in (None, "company", "person"):
            query = select(func.count(Contact.id)).where(
                Contact.tenant_id == tenant_id,
                Contact.deleted_at.is_(None),
            )
            if type_filter is not None:
                query = query.where(Contact.type == type_filter)
            query = await apply_visibility_filter(
                db, query, "contact", Contact, user_id, tenant_id, is_system_admin
            )
            queries.append(query)

        results = [((await db.execute(q)).scalar() or 0) for q in queries]
        return {
            "contacts": results[0],
            "companies": results[1],
            "persons": results[2],
            "total": results[0],
        }

    @staticmethod
    async def dsar_collect(
        db: AsyncSession, tenant_id: Any, user_id: Any
    ) -> dict[str, Any]:
        """GDPR Art. 15: collect contact data owned by the user.

        Owned by the contacts plugin — core/jobs.py calls this generically
        via the contract, it must not know contact internals.
        """
        contacts = (
            await db.execute(
                select(Contact).where(
                    Contact.tenant_id == tenant_id,
                    Contact.owner_id == user_id,
                    Contact.deleted_at.is_(None),
                )
            )
        ).scalars().all()
        return {
            "contacts": [
                {
                    "id": str(c.id),
                    "type": c.type,
                    "displayname": c.displayname,
                    "email_1": c.email_1,
                    "email_2": c.email_2,
                }
                for c in contacts
            ]
        }

    @staticmethod
    async def dsar_erase(
        db: AsyncSession, tenant_id: Any, user_id: Any
    ) -> dict[str, int]:
        """GDPR Art. 17: soft-delete contacts owned by the user.

        Soft-delete via deleted_at (audit history must remain intact — it is
        a business record, not personal data of the subject; retention
        policy governs its cleanup).
        """
        from datetime import UTC, datetime

        contacts = (
            await db.execute(
                select(Contact).where(
                    Contact.tenant_id == tenant_id,
                    Contact.owner_id == user_id,
                    Contact.deleted_at.is_(None),
                )
            )
        ).scalars().all()
        for c in contacts:
            c.deleted_at = datetime.now(UTC)
        return {"contacts_soft_deleted": len(contacts)}

    # ─── Import/Export contribution (W4a, Spec #359) ───
    # The contacts plugin owns its import/export domain logic; the core
    # orchestrator resolves formats via the format registry and enforces
    # the security policy (sensitive filter, tenant scoping, audit).

    IE_COLUMNS = {
        "contacts": ["firstname", "surname", "email", "phone", "mobile", "function", "department"],
        "companies": ["name", "industry", "phone", "email", "website"],
    }
    IE_TARGET_FIELDS = {
        "contacts": ["firstname", "surname", "email", "phone", "mobile", "function", "department"],
        "companies": ["name", "industry", "phone", "email", "website"],
    }
    IE_VALIDATORS = {
        "contacts": {"email": {"type": "email"}},
        "companies": {"email": {"type": "email"}, "website": {"type": "url"}},
    }

    @staticmethod
    def importexport_entities() -> list[str]:
        """Entity types offered by this plugin's import/export."""
        return ["contacts", "companies"]

    @staticmethod
    def importexport_formats() -> list[str]:
        """File formats this plugin's import/export supports."""
        return ["csv", "json", "xlsx"]

    @staticmethod
    def ie_columns(entity_type: str) -> list[str]:
        return list(ContactsContract.IE_COLUMNS[entity_type])

    @staticmethod
    def ie_target_fields(entity_type: str) -> list[str]:
        return list(ContactsContract.IE_TARGET_FIELDS[entity_type])

    @staticmethod
    def ie_validators(entity_type: str) -> dict[str, dict]:
        return dict(ContactsContract.IE_VALIDATORS[entity_type])

    @staticmethod
    def ie_normalize_row(entity_type: str, row: dict[str, str]) -> dict[str, str]:
        """Normalize an imported row to unified field names."""
        if entity_type == "contacts":
            firstname = (row.get("firstname") or row.get("first_name") or "").strip()
            surname = (row.get("surname") or row.get("last_name") or "").strip()
            row["firstname"] = firstname
            row["surname"] = surname
            if "email" not in row and "email_address" in row:
                row["email"] = row["email_address"]
            if "mobile" not in row and "phone_2" in row:
                row["mobile"] = row["phone_2"]
            if "function" not in row and "position" in row:
                row["function"] = row["position"]
            return row
        name = (row.get("name") or row.get("company") or row.get("company_name") or "").strip()
        row["name"] = name
        if "email" not in row and "email_address" in row:
            row["email"] = row["email_address"]
        if "website" not in row and "url" in row:
            row["website"] = row["url"]
        if "website" not in row and "homepage" in row:
            row["website"] = row["homepage"]
        return row

    @staticmethod
    def ie_required(entity_type: str) -> list[str]:
        """Required columns enforced by generic validate_row (old semantics)."""
        return ["name"] if entity_type == "companies" else []

    @staticmethod
    def ie_row_valid(entity_type: str, row: dict[str, str]) -> tuple[bool, str]:
        """Early either-or check for contacts only.

        NOTE: companies' required-name check must NOT happen here —
        generic validate_row(row, ['name'], validators) must see the row
        so a missing name AND an invalid email yield two errors (as the
        original semantics did).
        """
        if entity_type == "contacts":
            if not row.get("firstname") and not row.get("surname"):
                return False, "Missing required field: firstname or surname"
        return True, ""

    @staticmethod
    async def ie_fetch_rows(
        db: AsyncSession,
        tenant_id: Any,
        entity_type: str,
        user_id: Any = None,
        is_system_admin: bool = False,
        contact_type: str | None = None,
        search: str | None = None,
    ) -> tuple[list[str], list[dict[str, Any]]]:
        """Fetch export rows (headers + row dicts), visibility-filtered.

        Optional filters mirror the former export_service.py semantics:
        - contact_type: 'company' or 'person' (None = both)
        - search: FTS full-text search via contacts.search_tsv
        """
        from app.core.sensitive_data import get_sensitive_fields

        q = select(Contact).where(
            Contact.tenant_id == tenant_id,
            Contact.deleted_at.is_(None),
        )
        if entity_type == "companies":
            q = q.where(Contact.type == "company").order_by(Contact.name)
        else:
            if contact_type:
                q = q.where(Contact.type == contact_type)
            q = q.order_by(Contact.surname, Contact.firstname)
        if search:
            q = q.where(Contact.search_tsv.op("@@")(func.plainto_tsquery("german", search)))
        if user_id:
            q = await apply_visibility_filter(
                db, q, "contact", Contact, user_id, tenant_id, is_system_admin
            )
        records = (await db.execute(q)).scalars().all()

        # Sensitive-data safety net (core policy) — drop sensitive headers
        sensitive = get_sensitive_fields("contact")

        if entity_type == "companies":
            all_headers = ["id", "type", "name", "email", "phone", "website", "city", "postalcode", "country"]
            export_headers = [h for h in all_headers if h not in sensitive]
            rows = [
                {h: (getattr(c, h, None) or "") for h in export_headers}
                for c in records
            ]
        else:
            # Original export_service.py profile (test_performance.py contract):
            # 17 columns incl. displayname, code, email_1/email_2, phone_1/phone_2,
            # website, mailing_*, vat_code, tags — NOT the import profile.
            all_headers = [
                "id", "type", "displayname", "name", "firstname", "surname", "code",
                "email_1", "email_2", "phone_1", "phone_2", "website",
                "mailing_city", "mailing_postalcode", "mailing_country",
                "vat_code", "tags",
            ]
            export_headers = [h for h in all_headers if h not in sensitive]
            rows = [
                {h: (getattr(c, h, None) or "") for h in export_headers}
                for c in records
            ]
        return export_headers, rows

    @staticmethod
    async def ie_persist_row(
        db: AsyncSession,
        tenant_id: Any,
        user_id: Any,
        entity_type: str,
        row: dict[str, str],
    ) -> dict[str, Any]:
        """Persist one imported row as Contact; returns the serialized record."""
        from app.core.audit import log_audit
        from app.services.contact_service import _serialize_contact

        if entity_type == "companies":
            contact = Contact(
                tenant_id=tenant_id,
                type="company",
                name=row["name"].strip(),
                displayname=row["name"].strip(),
                email_1=row.get("email", "").strip() or None,
                phone_1=row.get("phone", "").strip() or None,
                website=row.get("website", "").strip() or None,
                owner_id=user_id,
                created_by=user_id,
                updated_by=user_id,
            )
        else:
            contact = Contact(
                tenant_id=tenant_id,
                type="person",
                firstname=row["firstname"].strip() or None,
                surname=row["surname"].strip() or None,
                displayname=f"{row['firstname']} {row['surname']}".strip(),
                email_1=row.get("email", "").strip() or None,
                phone_1=row.get("phone", "").strip() or None,
                phone_2=row.get("mobile", "").strip() or None,
                owner_id=user_id,
                created_by=user_id,
                updated_by=user_id,
            )
        db.add(contact)
        await db.flush()
        await log_audit(
            db,
            tenant_id,
            user_id,
            "import",
            "contact",
            contact.id,
            changes={
                "type": entity_type.rstrip("s"),
                "name": contact.name or f"{contact.firstname} {contact.surname}",
            },
        )
        return _serialize_contact(contact)

    # ─── Document Generator contribution (Phase L1, #359 pattern) ───
    # The documents generator resolves placeholders + entity data via these
    # contract hooks. Same philosophy as importexport_entities(): the module
    # owns its domain data, the generic renderer stays module-agnostic.

    @staticmethod
    def document_entity_types() -> list[str]:
        """Entity types this plugin serves in the documents generator."""
        return ["contact", "company", "person"]

    @staticmethod
    def document_placeholders(entity_type: str) -> list[dict]:
        """Placeholder descriptors (key/label/example) for the drag/drop editor."""
        return _placeholders_for(entity_type)

    @staticmethod
    async def document_data(
        db: AsyncSession,
        tenant_id: Any,
        entity_id: Any,
        entity_type: str,
    ) -> dict[str, Any]:
        """Load one entity as template data ({} when not found)."""
        contact = (
            await db.execute(
                select(Contact).where(
                    Contact.id == entity_id,
                    Contact.tenant_id == tenant_id,
                    Contact.deleted_at.is_(None),
                )
            )
        ).scalar_one_or_none()
        if contact is None:
            return {}
        fields = _contacts_document_fields()
        data: dict[str, Any] = {}
        for key in fields:
            value = getattr(contact, key, None)
            data[key] = value if value is not None else ""
        return data

    @classmethod
    def get_function(cls, name: str):
        """Return a callable exposed by this contract, or None if absent."""
        return getattr(cls, name, None)


# ─── self-registration ───

_contract = ContactsContract()
get_contract_registry().register("contacts", _contract)


def _contacts_document_fields() -> dict[str, str]:
    """Contact/company fields available in document templates (L1).

    Keys map to Contact model attributes; labels/examples feed the
    drag/drop editor palette and the preview fallback values.
    """
    return {
        "displayname": "Anzeigename",
        "firstname": "Vorname",
        "surname": "Nachname",
        "name": "Firmenname",
        "email": "E-Mail",
        "email_1": "E-Mail 1",
        "email_2": "E-Mail 2",
        "phone": "Telefon",
        "phone_1": "Telefon 1",
        "phone_2": "Telefon 2",
        "mobile": "Mobil",
        "website": "Website",
        "industry": "Branche",
        "city": "Stadt",
        "postalcode": "PLZ",
        "country": "Land",
        "vat_code": "USt-IdNr.",
        "function": "Funktion",
        "department": "Abteilung",
    }


_CONTACT_DOC_EXAMPLES = {
    "displayname": "Max Mustermann",
    "firstname": "Max",
    "surname": "Mustermann",
    "name": "Muster GmbH",
    "email": "max@example.com",
    "email_1": "max@example.com",
    "email_2": "buero@example.com",
    "phone": "+49 30 123456",
    "phone_1": "+49 30 123456",
    "phone_2": "+49 171 1234567",
    "mobile": "+49 171 1234567",
    "website": "https://example.com",
    "industry": "IT",
    "city": "Berlin",
    "postalcode": "10115",
    "country": "Deutschland",
    "vat_code": "DE123456789",
    "function": "Geschäftsführer",
    "department": "Vertrieb",
}


def _placeholders_for(entity_type: str) -> list[dict]:
    """Placeholder descriptors for contact/company templates."""
    if entity_type not in ("contact", "company", "person"):
        return []
    fields = _contacts_document_fields()
    result = []
    for key, label in fields.items():
        result.append({
            "key": key,
            "label": label,
            "example": _CONTACT_DOC_EXAMPLES.get(key, "…"),
        })
    return result