"""QE-VINTAGE-01/1.0: invented publication, archive-import and decision clocks.
Demo: January industrial production change relative to December in an imaginary country.
An invented statistical agency revises its initial estimate after receiving more responses.
value is a percentage: 2 means +2%, -1 means -1%. received_at records
when the program imports that publication into its data archive. UNAVAILABLE
means no supplied version can be used yet; it is not a measured zero or NO_BUY.
IT: caso inventato; produzione industriale gennaio/dicembre; value è percentuale.
received_at è l’importazione nell’archivio. UNAVAILABLE blocca la decisione per dato assente.
ES: caso inventado; producción industrial enero/diciembre; value es un porcentaje.
received_at es la importación al archivo. UNAVAILABLE bloquea la decisión por falta del dato.
No verified vendor latency, prediction, order execution or return calculation. Python 3.10+.
"""
import argparse
from datetime import datetime
import json
import math
from pathlib import Path


def instant(value):
    if not isinstance(value, str) or not value.endswith('Z'):
        raise ValueError('UTC_TIMESTAMP_REQUIRED')
    return datetime.fromisoformat(value[:-1] + '+00:00')


def demo():
    return {'case': 'QE-VINTAGE-01/1.0', 'synthetic': True,
            'versions': [
                {'period': '2026-01', 'version': 1, 'value': 2,
                 'published_at': '2026-02-01T09:00:00Z', 'received_at': '2026-02-01T09:05:00Z'},
                {'period': '2026-01', 'version': 2, 'value': -1,
                 'published_at': '2026-02-03T09:00:00Z', 'received_at': '2026-02-03T09:01:00Z'}],
            'decisions': [
                {'id': 'D1', 'period': '2026-01', 'at': '2026-02-01T09:02:00Z'},
                {'id': 'D2', 'period': '2026-01', 'at': '2026-02-01T09:10:00Z'},
                {'id': 'D3', 'period': '2026-01', 'at': '2026-02-03T09:00:00Z'},
                {'id': 'D4', 'period': '2026-01', 'at': '2026-02-03T09:02:00Z'}]}


def evaluate(data):
    versions = data['versions']; seen = set()
    for row in versions:
        key = (row['period'], row['version'])
        if key in seen:
            raise ValueError('DUPLICATE_VERSION')
        seen.add(key)
        if type(row['version']) is not int or row['version'] < 1:
            raise ValueError('VERSION_REQUIRED')
        if type(row['value']) not in (int, float) or not math.isfinite(row['value']):
            raise ValueError('FINITE_VALUE_REQUIRED')
        if instant(row['received_at']) < instant(row['published_at']):
            raise ValueError('RECEIPT_BEFORE_PUBLICATION')
    # Version numbers increase with publication time within an observation period.
    for period in {r['period'] for r in versions}:
        group = sorted((r for r in versions if r['period'] == period), key=lambda r:r['version'])
        if any(instant(b['published_at']) <= instant(a['published_at']) for a,b in zip(group,group[1:])):
            raise ValueError('VERSION_ORDER')
    rows = []; ids = set()
    for decision in data['decisions']:
        if decision['id'] in ids:
            raise ValueError('DUPLICATE_DECISION')
        ids.add(decision['id']); at = instant(decision['at'])
        group = [r for r in versions if r['period'] == decision['period']]
        eligible = [r for r in group if max(instant(r['published_at']),instant(r['received_at'])) <= at]
        selected = max(eligible, key=lambda r:r['version']) if eligible else None
        # Deliberately wrong comparator: today's value attached to first publication.
        latest = max(group,key=lambda r:r['version']) if group else None
        naive_green = bool(group) and min(instant(r['published_at']) for r in group) <= at
        rows.append({'decision':decision['id'], 'at':decision['at'],
                     'naive_time_check':naive_green,
                     'naive_value':latest['value'] if naive_green else None,
                     'selected_version':selected['version'] if selected else None,
                     'usable_value':selected['value'] if selected else None,
                     'action':'UNAVAILABLE' if selected is None else ('BUY' if selected['value'] > 0 else 'NO_BUY')})
    return {'case':'QE-VINTAGE-01/1.0','synthetic':True,'rows':rows,
            'scope':'Declared clocks and complete supplied vintages; no verified vendor latency, forecasts or market returns.'}


def main():
    parser=argparse.ArgumentParser(description=__doc__)
    parser.add_argument('--input',type=Path);parser.add_argument('--out',type=Path)
    args=parser.parse_args()
    data=json.loads(args.input.read_text('utf-8')) if args.input else demo()
    result=evaluate(data);output=json.dumps(result,ensure_ascii=False,allow_nan=False,indent=2)+'\n'
    if args.out:
        with args.out.open('x',encoding='utf-8') as f:f.write(output)
    else:print(output,end='')


if __name__=='__main__':main()