import datetime
from collections.abc import Sequence
from pathlib import Path

from db_models import WeatherForecast

_HEADERS = [
    "Дата",
    "Мин. темп. (°C)",
    "Макс. темп. (°C)",
    "Описание",
    "Влажность (%)",
    "Ветер (м/с)",
]


def _format_number(value: float) -> str:
    return f"{value:g}"


def export_md(records: Sequence[WeatherForecast], output_file: str, city: str) -> None:
    rows: list[list[str]] = []
    for record in sorted(records, key=lambda r: r.forecast_date):
        rows.append(
            [
                record.forecast_date.isoformat(),
                _format_number(record.temp_min),
                _format_number(record.temp_max),
                record.description or "",
                str(record.humidity),
                _format_number(record.wind_speed),
            ]
        )

    if records:
        dates: list[datetime.date] = [r.forecast_date for r in records]
        period = f"Период: {min(dates).isoformat()} - {max(dates).isoformat()}"
    else:
        period = "Период: -"

    location = f"Автоматически определённая локация: {city}"

    widths = [len(header) for header in _HEADERS]
    for row in rows:
        for i, cell in enumerate(row):
            widths[i] = max(widths[i], len(cell))

    def _row(row: list[str]) -> str:
        padded = [cell.ljust(widths[i]) for i, cell in enumerate(row)]
        return "| " + " | ".join(padded) + " |"

    separator = "| " + " | ".join("-" * width for width in widths) + " |"

    lines = [
        "# Прогноз погоды",
        "",
        location,
        period,
        "",
        _row(_HEADERS),
        separator,
        *(_row(row) for row in rows),
        "",
    ]
    Path(output_file).write_text("\n".join(lines), encoding="utf-8")