"""Build and validate the complete setup schedule before changing the application."""
from datetime import datetime, timedelta

from tests.config_reader import parse_product_codes


def build_plan(config, flow="configured", product_codes=None, now=None):
    now = now or datetime.now()
    setup = config.get("setup", {})
    session = flow in ("session", "both") or (
        flow == "configured" and setup.get("run_session", True)
    )
    token = flow in ("token", "both") or (
        flow == "configured" and setup.get("run_token", True)
    )
    result = {"session": None, "tokens": []}
    if session:
        settings = setup.get("session", {})
        start = now + timedelta(minutes=settings.get("start_offset_minutes", 7))
        end = datetime.combine(now.date(), datetime.strptime(settings.get("end_time", "20:30"), "%H:%M").time())
        if end <= start:
            raise ValueError("Session end_time must be later than its calculated start time. Update config.json.")
        result["session"] = (start.strftime("%d/%m/%Y %H:%M"), end.strftime("%d/%m/%Y %H:%M"))
    if token:
        settings = config.get("trading_token_idas")
        if not settings:
            raise ValueError("Configure trading_token_idas in config.json.")
        codes = parse_product_codes(product_codes if product_codes is not None else settings.get("product_codes") or settings.get("product_code"))
        if not codes or len(set(codes)) != len(codes):
            raise ValueError("Specify nonempty, unique token product codes.")
        expiry = datetime.combine(now.date(), datetime.strptime(settings.get("expiry_time", "20:30"), "%H:%M").time())
        if expiry <= now:
            raise ValueError("Token expiry_time is already past. Update config.json before creating tokens.")
        delivery = (now + timedelta(days=settings.get("delivery_offset_days", 1))).strftime("%d/%m/%Y")
        rows = []
        defaults = [("ORDER_NOR", (now + timedelta(minutes=10)).strftime("%H:%M"), "18:30"),
                    ("ORDER_EXCH", "18:30", "19:00"), ("TRADE", "19:00", "20:00")]
        for name, start, end in defaults:
            row = settings.get("time_sessions", {}).get(name, {})
            if row.get("start_time") is not None:
                start = row["start_time"]
            elif row.get("start_offset_minutes") is not None:
                start = (now + timedelta(minutes=row["start_offset_minutes"])).strftime("%H:%M")
            end = row.get("end_time", end)
            if datetime.strptime(end, "%H:%M") <= datetime.strptime(start, "%H:%M"):
                raise ValueError(f"{name} end_time must be later than start_time. Update config.json.")
            rows.append((name, start, end))
        result["tokens"] = [dict(settings, product_code=code, delivery_date=delivery,
                                 expiry=expiry.strftime("%d/%m/%Y %H:%M"),
                                 session_date=now.strftime("%d/%m/%Y"), rows=rows)
                            for code in codes]
    return result