交给DeepSeek写文案前，先核对发票行金额

"""Offline synthetic invoice check. No model/API request; USD integer cents only."""
import csv
import io
import json
import re

HEADER = ['line_id', 'description', 'qty', 'unit_usd', 'line_usd']
CSV = '''line_id,description,qty,unit_usd,line_usd
L1,Name badges,40,2.50,100.00
L2,Room signage,3,18.00,54.00
L3,Captioning service,2,45.00,80.00
'''

def cents(value):
    if not isinstance(value, str) or not re.fullmatch(r'[0-9]+\.[0-9]{2}', value):
        raise ValueError('Use unsigned USD amounts with exactly two decimals')
    whole, fraction = value.split('.')
    return int(whole) * 100 + int(fraction)

def check(text, invoice_total):
    reader = csv.reader(io.StringIO(text, newline=''), strict=True)
    if next(reader, None) != HEADER:
        raise ValueError('Unexpected CSV header')
    seen, rows, issues = set(), [], []
    for fields in reader:
        if len(fields) != len(HEADER):
            raise ValueError('Unexpected column count')
        ident, description, quantity, unit, quoted = fields
        if not ident or ident in seen or not description.strip():
            raise ValueError('Missing or duplicate line identity')
        if not re.fullmatch(r'[0-9]+', quantity) or int(quantity) < 1:
            raise ValueError('Quantity must be a positive whole number')
        seen.add(ident)
        expected, stated = int(quantity) * cents(unit), cents(quoted)
        rows.append(dict(line_id=ident, expected_cents=expected, stated_cents=stated))
        if expected != stated:
            issues.append(dict(line_id=ident, expected_cents=expected, stated_cents=stated))
    if not rows:
        raise ValueError('No invoice lines')
    declared = cents(invoice_total)
    expected_total = sum(x['expected_cents'] for x in rows)
    stated_sum = sum(x['stated_cents'] for x in rows)
    return dict(currency='USD', line_count=len(rows), line_issues=issues,
                expected_total_cents=expected_total, stated_line_sum_cents=stated_sum,
                declared_total_cents=declared, declared_matches_lines=declared == stated_sum,
                eligible_for_draft=not issues and declared == expected_total)

def draft_brief(report):
    if not report['eligible_for_draft']:
        raise ValueError('Resolve arithmetic before creating a drafting brief')
    return {k: report[k] for k in ['currency', 'line_count', 'expected_total_cents']}

def planned_microcredits(inputs, outputs, rate_in, rate_out):
    if any(type(x) is not int or x < 0 for x in [inputs, outputs, rate_in, rate_out]):
        raise ValueError('Planning quantities and rates must be nonnegative integers')
    numerator = inputs * rate_in + outputs * rate_out
    return (numerator + 999999) // 1000000

if __name__ == '__main__':
    bad = check(CSV, '234.00')
    assert bad['declared_matches_lines'] and not bad['eligible_for_draft']
    assert bad['expected_total_cents'] - bad['declared_total_cents'] == 1000
    try:
        draft_brief(bad)
    except ValueError:
        pass
    else:
        raise AssertionError('Bad invoice became a drafting brief')
    fixed = check(CSV.replace('45.00,80.00', '45.00,90.00'), '244.00')
    assert draft_brief(fixed) == dict(currency='USD', line_count=3, expected_total_cents=24400)
    rejected = 0
    for text, total in [
        (CSV.replace('L2,', 'L1,'), '234.00'),
        (CSV.replace(',40,', ',0,'), '234.00'),
        (CSV.replace(',40,', ',1e2,'), '234.00'),
        (CSV.replace('2.50', '2.500'), '234.00'),
        (CSV.replace('2.50', '-2.50'), '234.00'),
        (CSV.replace('L1,Name badges,', 'L1,Name badges,EXTRA,'), '234.00'),
        (CSV, '234,00'),
    ]:
        try:
            check(text, total)
        except ValueError:
            rejected += 1
        else:
            raise AssertionError('Invalid fixture accepted')
    rates = {'catalog_low': (18333360, 73333440), 'catalog_high': (36666720, 146666880)}
    plans = {key: planned_microcredits(1000, 300, *value) for key, value in rates.items()}
    assert plans == {'catalog_low': 40334, 'catalog_high': 80667}
    print(json.dumps(dict(bad=bad, corrected_brief=draft_brief(fixed),
                         negative_fixtures_rejected=rejected, planned_microcredits=plans), indent=2))