"""Serialize explicit ordered rows to the existing ARR processor XML format.

No API selection, report semantics, filtering, deduplication or pricing occurs
here. Output is a processing projection, not a native Opera report replica.
"""
from __future__ import annotations

import xml.etree.ElementTree as ET

from .arr_xml_contract import MAX_BYTES, SCALARS, SourceDocument, validate_document
from .collect_arr_source import require


def serialize(document: SourceDocument) -> bytes:
    validate_document(document)
    root = ET.Element("RES_DETAIL")
    groups = ET.SubElement(root, "LIST_G_GROUP_BY1")
    group = ET.SubElement(groups, "G_GROUP_BY1")
    day = document.report_date
    ET.SubElement(group, "GROUPBY1_SORT_COL").text = f"{day.year:04d}{day.month:02d}{day.day:02d}"
    # Use the full-year ISO representation accepted by the existing processor.
    # A two-digit display year can silently map historical dates to another century.
    ET.SubElement(group, "GROUPBY1_COL").text = document.report_date.isoformat()
    rows = ET.SubElement(group, "LIST_G_RESERVATION")
    for row in document.rows:
        node = ET.SubElement(rows, "G_RESERVATION")
        ET.SubElement(node, "RESORT").text = document.hotel_id
        ET.SubElement(node, "RESV_NAME_ID").text = row.reservation_id
        for attribute, tag in SCALARS:
            ET.SubElement(node, tag).text = getattr(row, attribute)
        comments = ET.SubElement(node, "LIST_G_COMMENT_RESV_NAME_ID")
        for text in row.notes:
            ET.SubElement(ET.SubElement(comments, "G_COMMENT_RESV_NAME_ID"), "RES_COMMENT").text = text
        traces = ET.SubElement(node, "LIST_G_DEPT_ID")
        for text in row.traces:
            ET.SubElement(ET.SubElement(traces, "G_DEPT_ID"), "TRACE_TEXT").text = text
    # XML parsers normalize literal CR; character references preserve it exactly.
    raw = ET.tostring(root, encoding="utf-8", xml_declaration=True).replace(b"\r", b"
") + b"\n"
    require(len(raw) <= MAX_BYTES, "arr_xml_output_budget_exceeded")
    return raw