"""
Rename files in SharePoint property folders to the canonical format:
    {UPRN}_{Street} {Postcode}_{Document Name}.ext

Set DRY_RUN = False when ready to commit. Run from repo root.
Required env vars: SHAREPOINT_CLIENT_ID, SHAREPOINT_CLIENT_SECRET,
                   SHAREPOINT_TENANT_ID, SOCIAL_HOUSING_WAVE_3_SHAREPOINT_ID
"""

import csv
import os
from typing import Optional

from backend.pashub_fetcher.sharepoint_subfolders import SharepointSubfolders
from utils.logger import setup_logger
from utils.sharepoint.domna_sharepoint_client import DomnaSharepointClient
from utils.sharepoint.domna_sites import DomnaSites

DRY_RUN: bool = True
CSV_PATH: str = "scripts/sero_address_list.csv"

BASE_PATH = (
    "Osmosis-ACD Projects/Sero-Clarion Housing/"
    "Sero Project Documents/Property Folders"
)
ASSESSMENT_SUBFOLDER = "A. Assessment"

logger = setup_logger()


def build_canonical_filename(
    uprn: str, address: str, postcode: str, original_name: str
) -> Optional[str]:
    """
    Returns the canonical filename, or None if the file is already renamed.

    Already-renamed: name starts with "{uprn}_".
    Strips any existing address prefix (address+postcode first, then address alone)
    before inserting the canonical prefix.
    """
    if original_name.startswith(f"{uprn}_"):
        return None

    stem, ext = os.path.splitext(original_name)
    stem_lower = stem.lower()

    street = address.split(",")[0].strip()
    prefixes = [
        f"{address} {postcode}",
        address,
        f"{street} {postcode}",
        street,
    ]

    doc_name = stem
    for prefix in prefixes:
        if stem_lower.startswith(prefix.lower()):
            doc_name = stem[len(prefix) :]
            break

    if doc_name.startswith(" - "):
        doc_name = doc_name[3:]
    elif doc_name.startswith(" _ "):
        doc_name = doc_name[3:]
    doc_name = doc_name.strip()

    street_post = f"{street} {postcode}"
    if doc_name:
        return f"{uprn}_{street_post}_{doc_name}{ext}"
    return f"{uprn}_{street_post}{ext}"


def main() -> None:
    sp_client = DomnaSharepointClient(DomnaSites.SOCIAL_HOUSING_WAVE_3)

    with open(CSV_PATH, newline="", encoding="utf-8-sig") as f:
        reader = csv.DictReader(f)
        required = {"UPRN", "Address", "Postcode"}
        if not reader.fieldnames or not required.issubset(set(reader.fieldnames)):
            raise ValueError(
                f"CSV missing required columns. Expected {required}, got {reader.fieldnames}"
            )

        for row in reader:
            uprn = row["UPRN"].strip()
            address = row["Address"].strip()
            postcode = row["Postcode"].strip()
            folder_path = (
                f"{BASE_PATH}/{address}, {postcode}"
                f"/{SharepointSubfolders.ASSESSMENT.value}/{ASSESSMENT_SUBFOLDER}"
            )

            try:
                contents = sp_client.get_folders_in_path(folder_path)
            except ValueError:
                logger.warning(f"Missing folder for UPRN {uprn}: {folder_path}")
                continue

            for item in contents.get("value", []):
                if "file" not in item:
                    continue

                original_name: str = item["name"]
                new_name = build_canonical_filename(
                    uprn, address, postcode, original_name
                )

                if new_name is None:
                    continue

                if DRY_RUN:
                    logger.info(
                        f'[DRY RUN] Renaming: "{original_name}" → "{new_name}" (UPRN: {uprn})'
                    )
                else:
                    try:
                        sp_client.rename_file(item["id"], new_name)
                        logger.info(
                            f'Renamed: "{original_name}" → "{new_name}" (UPRN: {uprn})'
                        )
                    except Exception as e:
                        logger.error(
                            f'Failed to rename "{original_name}" → "{new_name}" (UPRN: {uprn}): {e}'
                        )


if __name__ == "__main__":
    main()