"""Resolve same-conversation quote edits and return local facts without model I/O."""

from decimal import Decimal, InvalidOperation
import re
import sqlite3

from .db import connect
from .quote_data import load_book, postcode_fee
from .quote_engine import US, QUOTE_WORDS, parse_intent, is_followup, variants, render_rates


def intent_with_context(message, conv_id, book):
    from copy import deepcopy
    codes = {row['code'] for row in book['warehouses']}
    codes.update(value.upper() for rate in book['rates'] for value in rate['destinations'])
    intent = parse_intent(message,codes)
    def destination_reset(value):
        if value.get('warehouse') or value.get('unknown_warehouses'):return {'postal','zone','zones'}
        if value.get('postal'):return {'warehouse','warehouses','unknown_warehouses','zone','zones'}
        if value.get('zone'):return {'warehouse','warehouses','unknown_warehouses','postal'}
        return set()
    excluded=destination_reset(intent)
    selected_destination=bool(excluded)
    if selected_destination and not intent.get('unknown_warehouses'):excluded.add('unknown_warehouses')
    if intent['transport'] or intent['kinds'] or intent['services']:excluded.update(('air_only','air_requested'))
    if intent['air_only'] or intent['tax']=='excluded':excluded.add('kinds')
    if intent.get('weight') is not None and not intent.get('packages'):excluded.add('packages')
    explicit_dims=bool(intent['dims'])
    if conv_id and is_followup(message,intent):
        connection=connect()
        try:
            recent=connection.execute("SELECT content FROM messages WHERE conv_id=? AND role='user' ORDER BY id DESC LIMIT 10",(conv_id,)).fetchall()
        finally:connection.close()
        for (previous,) in recent:
            if re.search(r'理赔|赔偿|破损|丢失|退件|投诉|查单|轨迹|签收',previous):break
            earlier=parse_intent(previous,codes)
            if earlier['country']=='other':break
            if not (QUOTE_WORDS.search(previous) or US.search(previous) or is_followup(previous,earlier) or
                    any(earlier.get(key) for key in ('weight','dims','cbm','warehouse','postal'))):break
            if not selected_destination and destination_reset(earlier):
                excluded.update(destination_reset(earlier));selected_destination=True
            if intent['dims'] is None and earlier['dims']:
                intent['dims']=earlier['dims'];intent['dim_unit']=earlier['dim_unit']
            for key,value in earlier.items():
                if key in ('mode','text','errors','dim_unit','dims'):continue
                if intent.get(key) is None and key not in excluded:intent[key]=deepcopy(value)
            if not is_followup(previous,earlier):break
    if explicit_dims and intent.get('packages'):
        for piece in intent['packages']:
            piece['dims']=intent['dims'];piece['dim_unit']=intent['dim_unit']
    if (intent['warehouse'] or intent.get('unknown_warehouses')) and intent['country'] is None:intent['country']='US'
    return intent


def answer_quote(message, conv_id):
    if re.search(r'理赔|赔偿|破损|丢失|退件|投诉|查单|轨迹|签收', message):
        return None
    # Avoid a new read for ordinary chat; short followups need their local context.
    if not (US.search(message) or QUOTE_WORDS.search(message) or conv_id or
            re.search(r'(?<![A-Za-z0-9])[A-Za-z]{2,4}[0-9](?![A-Za-z0-9])', message)):
        return None
    try:
        book = load_book()
        if not book:
            return None
        intent = intent_with_context(message, conv_id, book)
        if intent['country'] != 'US':
            return None
        if intent.get('errors'):
            return {'t':'\n'.join(intent['errors'])}
        if intent.get('unknown_warehouses'):
            return {'t':'未找到目的仓码 '+ '、'.join(intent['unknown_warehouses'])+'，请核对仓码，或提供5位美国邮编继续查询。'}
        if not (QUOTE_WORDS.search(message) or is_followup(message,intent) or
                any(intent.get(key) for key in ('weight','dims','cbm','warehouse','postal'))):
            return None
        for key in ('weight','cbm'):
            if intent[key] is not None and not (Decimal(0) < Decimal(intent[key]) <= Decimal(1000000)):
                return {'t':'请提供大于 0 的有效重量或体积。'}
        if intent['boxes'] is not None and not 0 < intent['boxes'] <= 10000:
            return {'t':'请提供有效的货物箱数。'}
        dimensions=[intent['dims']] if intent['dims'] else []
        dimensions += [piece['dims'] for piece in intent.get('packages') or [] if piece.get('dims')]
        if any(not 0 < value <= 100000 for dims in dimensions for value in dims):
            return {'t':'请提供大于 0 的有效长宽高。'}
        from .quote_answers import answer_business
        business=answer_business(intent,book)
        if business is not None:return {'t':business}
        if intent['air_only']:
            return {'t':'当前美国报价资料包含美森、EXX、合德及普船的海卡、海铁和海派。发我目的仓码或邮编、重量，可以列出这些线路的价格；空运费率当前资料没有列出。'}
        destinations = variants(intent,book)
        fees = []
        for destination in destinations:
            postal = destination['postal']
            if postal and (postal[:3] in ('006','007','008','009','966','967','968','969','995','996','997','998','999') or postal=='89124'):
                return {'t':f'当前海派资料不接收邮编 {postal} 的地址，请提供其他目的仓码或联系人工确认可用线路。'}
            fees.append(postcode_fee(book['id'],postal) if postal else None)
        return {'t':render_rates(intent,book,destinations,fees)}
    except (sqlite3.Error, ValueError, KeyError, TypeError, InvalidOperation):
        return {'t':'报价数据暂时无法读取，请稍后重试。'}