from __future__ import annotations

import os
from pathlib import Path

import pytest

from tenbackward.config import ConfigError, load_config, validate_config


def _populate(env_setup) -> dict[str, str]:
    return {k: os.environ[k] for k in os.environ if k.startswith(("MASTODON_", "SITE_", "HASHTAGS", "RUN_AT", "THROWBACK_", "RETRY_", "TZ"))}


def test_load_config_succeeds_with_complete_env(env_setup) -> None:
    config = load_config()
    assert config.mastodon_base_url == "https://mastodon.example"
    assert config.run_at == "09:00"
    assert config.retry_count == 3
    assert config.throwback_prefix == "Throwback:"


def test_validate_config_lists_every_missing_key(env_setup, monkeypatch) -> None:
    monkeypatch.delenv("MASTODON_ACCESS_TOKEN")
    monkeypatch.delenv("SITE_URL")

    values = {k: os.environ.get(k, "") for k in [
        "MASTODON_BASE_URL",
        "MASTODON_ACCESS_TOKEN",
        "SITE_URL",
        "HASHTAGS",
        "RUN_AT",
    ]}

    with pytest.raises(ConfigError) as excinfo:
        validate_config(values)

    message = str(excinfo.value)
    assert "MASTODON_ACCESS_TOKEN" in message
    assert "SITE_URL" in message


def test_validate_config_rejects_bad_run_at() -> None:
    values = {
        "MASTODON_BASE_URL": "https://mastodon.example",
        "MASTODON_ACCESS_TOKEN": "x",
        "SITE_URL": "https://blog.example.com",
        "HASHTAGS": "#x",
        "RUN_AT": "25:99",
        "MASTODON_VISIBILITY": "public",
        "THROWBACK_PREFIX": "Throwback:",
        "RETRY_COUNT": "3",
        "TZ": "Europe/Berlin",
    }
    with pytest.raises(ConfigError):
        validate_config(values)


def test_load_config_applies_optional_defaults(env_setup, monkeypatch) -> None:
    monkeypatch.delenv("THROWBACK_PREFIX", raising=False)
    monkeypatch.delenv("RETRY_COUNT", raising=False)

    config = load_config()
    assert config.throwback_prefix == "Throwback:"
    assert config.retry_count == 3
    assert config.tz == "Europe/Berlin"
    assert config.mastodon_visibility == "public"


def test_load_config_reads_dotenv_file(tmp_path: Path, monkeypatch) -> None:
    dotenv = tmp_path / ".env"
    dotenv.write_text(
        "MASTODON_BASE_URL=https://from-file.example\n"
        "MASTODON_ACCESS_TOKEN=file-token\n"
        "SITE_URL=https://blog.example.com\n"
        "HASHTAGS=#throwback\n"
        "RUN_AT=12:34\n"
    )

    for key in ("MASTODON_BASE_URL", "MASTODON_ACCESS_TOKEN", "SITE_URL", "HASHTAGS", "RUN_AT"):
        monkeypatch.delenv(key, raising=False)

    config = load_config(dotenv_path=dotenv)
    assert config.mastodon_base_url == "https://from-file.example"
    assert config.mastodon_access_token == "file-token"
    assert config.run_at == "12:34"


def test_env_overrides_dotenv(tmp_path: Path, monkeypatch) -> None:
    dotenv = tmp_path / ".env"
    dotenv.write_text("RUN_AT=01:00\n")

    monkeypatch.setenv("RUN_AT", "23:00")
    for key in (
        "MASTODON_BASE_URL",
        "MASTODON_ACCESS_TOKEN",
        "SITE_URL",
        "HASHTAGS",
    ):
        monkeypatch.setenv(key, "x")

    config = load_config(dotenv_path=dotenv)
    assert config.run_at == "23:00"