import re
from dataclasses import dataclass, asdict
from typing import Optional, Dict, Any, Type, TypeVar
from sqlalchemy.orm import Session

from enum import Enum
from datetime import datetime, timedelta
import math
import pytz
import enum

from backend.app.db.models.inspections import (
    InspectionModel,
    InspectionArchetype,
    InspectionArchetype2,
    InspectionsWallConstruction,
    InspectionsWallInsulation,
    InspectionsInsulationMaterial,
    InspectionBorescoped,
    InspectionsRoofOrientation,
    InspectionsTileHung,
    InspectionsRendered,
    InspectionsCladding,
    InspectionsAccessIssues,
)

NON_INTRUSIVE_PREFIX = "non-intrusives:"


@dataclass
class InspectionData:
    archetype: Optional[InspectionArchetype] = None
    archetype_2: Optional[InspectionArchetype2] = None
    wall_construction: Optional[InspectionsWallConstruction] = None
    insulation: Optional[InspectionsWallInsulation] = None
    insulation_material: Optional[InspectionsInsulationMaterial] = None
    borescoped: Optional[InspectionBorescoped] = None
    roof_orientation: Optional[InspectionsRoofOrientation] = None
    tile_hung: Optional[InspectionsTileHung] = None
    rendered: Optional[InspectionsRendered] = None
    cladding: Optional[InspectionsCladding] = None
    access_issues: Optional[InspectionsAccessIssues] = None
    date: Optional[datetime] = None  # Reflects the date when the survey was actually conducted
    notes: Optional[str] = None
    surveyor_name: Optional[str] = None


def _clean_string(value: Any) -> Optional[str]:
    """Normalize strings for enum matching, tolerant of NaN/None."""
    if value is None:
        return None
    if isinstance(value, float) and math.isnan(value):
        return None
    if not isinstance(value, str):
        return None

    v = (
        value.strip()
        .lower()
        .replace("“", '"')
        .replace("”", '"')
        .replace("’", "'")
    )
    return re.sub(r"\s+", " ", v)


E = TypeVar("E", bound=Enum)


def _match_enum(value: Any, enum_cls: Type[E]) -> Optional[E]:
    """Case-insensitive fuzzy matching for enums, tolerant of NaN/None."""
    v = _clean_string(value)
    if not v:
        return None

    for e in enum_cls:
        if v == e.value.lower():
            return e

    for e in enum_cls:
        if v in e.value.lower() or e.value.lower() in v:
            return e

    return None


def _lower_key_dict(d: dict) -> dict:
    """Convert all keys to lowercase for case-insensitive lookup."""
    return {str(k).lower(): v for k, v in d.items() if isinstance(k, str)}


def extract_inspection_data(config: Dict[str, Any]) -> Optional[InspectionData]:
    """Extract and map inspection data from a config row."""
    config_lower = _lower_key_dict(config)

    non_intrusive_fields = {
        k: v for k, v in config_lower.items()
        if k.startswith(NON_INTRUSIVE_PREFIX)
    }

    if not non_intrusive_fields:
        return None

    data = InspectionData()

    data.archetype = _match_enum(
        config_lower.get("non-intrusives: archetype"), InspectionArchetype
    )
    data.archetype_2 = _match_enum(
        config_lower.get("non-intrusives: archetype 2"), InspectionArchetype2
    )
    data.wall_construction = _match_enum(
        config_lower.get("non-intrusives: construction"), InspectionsWallConstruction
    )
    data.insulation = _match_enum(
        config_lower.get("non-intrusives: insulated"), InspectionsWallInsulation
    )
    data.insulation_material = _match_enum(
        config_lower.get("non-intrusives: material"), InspectionsInsulationMaterial
    )
    data.borescoped = _match_enum(
        config_lower.get("non-intrusives: boroscoped?"), InspectionBorescoped
    )
    data.roof_orientation = _match_enum(
        config_lower.get("non-intrusives: roof orientation"), InspectionsRoofOrientation
    )
    data.tile_hung = _match_enum(
        config_lower.get("non-intrusives: tile hung"), InspectionsTileHung
    )
    data.rendered = _match_enum(
        config_lower.get("non-intrusives: rendered"), InspectionsRendered
    )
    data.cladding = _match_enum(
        config_lower.get("non-intrusives: cladding"), InspectionsCladding
    )
    data.access_issues = _match_enum(
        config_lower.get("non-intrusives: access issues"), InspectionsAccessIssues
    )

    data.date = config_lower.get("non-intrusives: date")
    data.notes = config_lower.get("non-intrusives: further surveyor notes")
    # convert surveyor name to title case if present
    data.surveyor_name = config_lower.get("non-intrusives: name of surveyor").title() if config_lower.get(
        "non-intrusives: name of surveyor") else None

    return data


def bulk_upsert_inspections_pg(session: Session, inspections_map):
    """
    Bulk insert/update inspection records:
      - 'created_at' = actual survey date
      - 'uploaded_at' = time of upload or update
      - If an inspection exists for the same property on the same date → overwrite
      - Otherwise → insert a new record
    """

    if not inspections_map:
        return

    now = datetime.now(pytz.utc)

    for property_id, data in inspections_map.items():
        # Extract survey date from the data
        record = asdict(data)
        survey_date = getattr(data, "survey_date", None) or record.get("survey_date")

        if not survey_date:
            continue  # skip if no survey date available

        # Convert to UTC datetime if needed
        if hasattr(survey_date, "to_pydatetime"):
            survey_date = survey_date.to_pydatetime()
        if survey_date.tzinfo is None:
            survey_date = survey_date.replace(tzinfo=pytz.utc)

        record["property_id"] = property_id
        record["created_at"] = survey_date
        record["uploaded_at"] = now

        # Normalize enums and NaNs
        for key, value in record.items():
            if isinstance(value, enum.Enum):
                record[key] = value.value
            elif isinstance(value, float) and math.isnan(value):
                record[key] = None

        # Find existing inspection *for same property on same day*
        start_of_day = survey_date.replace(hour=0, minute=0, second=0, microsecond=0)
        end_of_day = start_of_day + timedelta(days=1)

        existing_inspection = (
            session.query(InspectionModel)
            .filter(
                InspectionModel.property_id == property_id,
                InspectionModel.created_at >= start_of_day,
                InspectionModel.created_at < end_of_day,
            )
            .first()
        )

        if existing_inspection:
            # Overwrite existing record (same survey day)
            for field, value in record.items():
                setattr(existing_inspection, field, value)
            existing_inspection.uploaded_at = now
        else:
            # Create new inspection for new day
            new_inspection = InspectionModel(**record)
            session.add(new_inspection)

    session.flush()