"""Ledger Vat Summary logic."""

from datetime import datetime

from fastapi import HTTPException

from moneyhub import models
from moneyhub.constants.constants import ABACUS_EVENT_BACKFILL
from moneyhub.constants.constants import SYSTEM_TIMEZONE
from moneyhub.schemas.ledger_vat_summary import LedgerVatSummaryBackfillSchema
from moneyhub.schemas.ledger_vat_summary import PaginatedLedgerVatSummarySchema
from moneyhub.utils.request import create_paginated_response
from moneyhub.utils.users import get_user_id


def backfill_vat_summary_entries(
    statement_period_id: int,
    data: list[LedgerVatSummaryBackfillSchema]
) -> list:
    """Backfill VAT summary entries based on a data payload.

    Args:
        statement_period_id (int): Statement period to backfill entries for.
        data (list): List of VAT summary entries to backfill.
    Returns:
        list: List of created VAT summary entries
    """
    existing_entries = models.LedgerVatSummary.get_by_statement_period(statement_period_id)
    existing_entries = [
        f'{e.account_id}-{e.contract_id}-{e.vat_category}-{float(e.base_amount_payee_currency)}'
        for e in existing_entries
    ]

    adjustments = models.WorksheetAdjustment.get_vat_adjustments(statement_period_id)

    adjustment_event_map = {
        f'{a.account_id}-{a.contract_id}-{a.adjustment_currency_code}-{float(a.adjustment_amount)}' : a.abacus_event_id  # noqa: E501
        for a in adjustments
    }

    date_now = datetime.now(SYSTEM_TIMEZONE)
    user_id = get_user_id()

    new_vat_summary_entries = []
    for entry in data:
        entry_key = f'{entry.account_id}-{entry.contract_id}-{entry.vat_category}-{float(entry.base_amount_payee_currency)}'  # noqa: E501
        if entry_key in existing_entries:
            continue

        adjustment_key = f'{entry.account_id}-{entry.contract_id}-{entry.payee_currency_code}-{float(entry.vat_amount_payee_currency)}'  # noqa: E501
        if adjustment_key not in adjustment_event_map:
            raise HTTPException(
                status_code=400,
                detail=f'Missing adjustment for key: {adjustment_key}')

        adjustment_event_id = adjustment_event_map[adjustment_key]

        abacus_event = models.AbacusEvent.create(
            statement_period_id=statement_period_id,
            event_name=ABACUS_EVENT_BACKFILL,
            target_type='statement_period',
            target_id=statement_period_id,
            event_date=date_now,
            previous_abacus_event_id=adjustment_event_id,
            created_by=user_id,
        )

        vat_summary_entry = models.LedgerVatSummary.create(
            statement_period_id=statement_period_id,
            activity_statement_period_id=statement_period_id,
            abacus_event_id=abacus_event.abacus_event_id,
            account_id=entry.account_id,
            contract_id=entry.contract_id,
            vat_category=entry.vat_category,
            payee_currency_code=entry.payee_currency_code,
            vat_currency_code=entry.vat_currency_code,
            base_amount_payee_currency=entry.base_amount_payee_currency,
            vat_rate=entry.vat_rate,
            vat_amount_payee_currency=entry.vat_amount_payee_currency,
            vat_amount_vat_currency=entry.vat_amount_vat_currency,
            wht_amount_payee_currency=entry.wht_amount_payee_currency,
            wht_amount_vat_currency=entry.wht_amount_vat_currency,
            wht_rate=entry.wht_rate,
            net_amount_payee_currency=entry.net_amount_payee_currency,
            is_reporting_only=True,
            created_by=user_id,
            created_at=date_now,
            last_modified_by=user_id,
            last_modified=date_now,
        )

        new_vat_summary_entries.append(vat_summary_entry)

    return new_vat_summary_entries


def get_by_account_id(
        account_id: int,
        statement_period_id: int,
        contract_id: int | None,
        vat_categories: list | None
) -> list:
    """GET ledger vat summary for a specified account and statement period.

    Args:
        account_id (int): The id of an account
        contract_id (int): the id of a contract
        statement_period_id (int): the id of a statement period
        vat_categories (list): vat categories to filter
    Returns:
        list: list of ledger vat
    """
    vat_summary = models.LedgerVatSummary.get_by_account_id(
        account_id=account_id,
        statement_period_id=statement_period_id,
        contract_id=contract_id,
        vat_categories=vat_categories
    )
    return vat_summary


def get_activity_by_account_id(
        account_id: int,
        statement_period_id: int,
        contract_id: int | None,
        vat_categories: list | None
) -> list:
    """GET ledger vat summary for a specified account and activity statement period.

    Args:
        account_id (int): The id of an account
        contract_id (int): the id of a contract
        statement_period_id (int): the id of a statement period
        vat_categories (list): vat categories to filter
    Returns:
        list: list of ledger vat
    """
    vat_summary = models.LedgerVatSummary.get_by_account_id(
        account_id=account_id,
        activity_statement_period_id=statement_period_id,
        contract_id=contract_id,
        vat_categories=vat_categories
    )
    return vat_summary


def get_by_vat_summary_file(
    vat_summary_file_id: int,
    limit: int,
    offset: int
) -> PaginatedLedgerVatSummarySchema:
    """Get the ledger VAT summary entries associated with a VAT summary file.

    Args:
        vat_summary_file_id (int): ID of the VAT summary file
        limit (int): how many entities to retrieve
        offset (int): the offset (for pagination)
    Returns:
        PaginatedLedgerVatSummarySchema: paginated list of ledger VAT summary entries
    """
    (entries, total_records) = models.LedgerVatSummary.get_by_vat_summary_file(
        vat_summary_file_id, limit, offset)

    payload = create_paginated_response(entries, total_records)
    return PaginatedLedgerVatSummarySchema(**payload)