from __future__ import annotations

from pathlib import Path
import hashlib
import json
import secrets
import tempfile

from sqlalchemy import create_engine
from sqlalchemy.orm import Session, sessionmaker

from app.core import admin_secret
from app.core import secret_box
from app.db.base import Base
from app.models.system_model_setting import SystemModelSetting
from app.models.system_setting import SystemSetting
from app.models.system_setting_secret import SystemSettingSecret
from app.schemas.settings import SettingsWrite
from app.services.settings import SettingsService


def build_session(db_file: Path) -> Session:
    engine = create_engine(
        f"sqlite+pysqlite:///{db_file.as_posix()}",
        connect_args={"check_same_thread": False},
    )
    SystemSetting.__table__.create(bind=engine)
    SystemSettingSecret.__table__.create(bind=engine)
    SystemModelSetting.__table__.create(bind=engine)
    session_factory = sessionmaker(bind=engine, autoflush=False, autocommit=False)
    return session_factory()


def build_temp_secret_dir() -> Path:
    return Path(tempfile.mkdtemp(prefix="xf-settings-test-"))


def test_settings_service_persists_non_secret_and_secret_fields(monkeypatch) -> None:
    temp_dir = build_temp_secret_dir()
    monkeypatch.setattr(secret_box, "SECRET_KEY_FILE", temp_dir / "settings.key")
    monkeypatch.setattr(Base.metadata, "create_all", lambda *args, **kwargs: None)

    with build_session(temp_dir / "settings.db") as db:
        service = SettingsService(db)
        initial_snapshot = service.get_settings_snapshot()
        payload = initial_snapshot.model_dump()

        payload["companyForm"]["companyName"] = "YGSOFT"
        payload["companyForm"]["displayName"] = "云广软件"
        payload["adminForm"]["adminAccount"] = "admin-root"
        payload["adminForm"]["adminEmail"] = "admin@example.com"
        payload["adminForm"]["newPassword"] = "54321"
        payload["adminForm"]["confirmPassword"] = "54321"
        payload["llmForm"]["mainModel"] = "glm-4.5"
        payload["llmForm"]["mainApiKey"] = "main-secret"
        payload["mailForm"]["password"] = "smtp-secret"

        saved_snapshot = service.save_settings_snapshot(SettingsWrite(**payload))

        assert saved_snapshot.companyForm.companyName == "YGSOFT"
        assert saved_snapshot.companyForm.displayName == "云广软件"
        assert saved_snapshot.llmForm.mainModel == "glm-4.5"
        assert saved_snapshot.llmForm.mainApiKey == ""
        assert saved_snapshot.llmForm.mainApiKeyConfigured is True
        assert saved_snapshot.mailForm.password == ""
        assert saved_snapshot.mailForm.passwordConfigured is True
        assert saved_snapshot.adminForm.newPassword == ""
        assert saved_snapshot.adminForm.adminPasswordConfigured is True

        model_row = db.get(SystemModelSetting, "main")
        assert model_row is not None
        assert model_row.model_name == "glm-4.5"
        assert model_row.api_key_encrypted

        assert service.load_saved_model_api_key("main") == "main-secret"
        assert service.verify_admin_login("admin-root", "54321") is not None
        assert service.verify_admin_login("admin@example.com", "54321") is not None


def test_blank_secret_input_does_not_clear_saved_secret(monkeypatch) -> None:
    temp_dir = build_temp_secret_dir()
    monkeypatch.setattr(secret_box, "SECRET_KEY_FILE", temp_dir / "settings.key")
    monkeypatch.setattr(Base.metadata, "create_all", lambda *args, **kwargs: None)

    with build_session(temp_dir / "settings.db") as db:
        service = SettingsService(db)
        first_payload = service.get_settings_snapshot().model_dump()
        first_payload["llmForm"]["mainApiKey"] = "persisted-key"
        service.save_settings_snapshot(SettingsWrite(**first_payload))

        second_payload = service.get_settings_snapshot().model_dump()
        second_payload["llmForm"]["mainApiKey"] = ""
        service.save_settings_snapshot(SettingsWrite(**second_payload))

        assert service.load_saved_model_api_key("main") == "persisted-key"


def test_legacy_setup_admin_password_is_migrated_to_database(monkeypatch) -> None:
    temp_dir = build_temp_secret_dir()
    admin_file = temp_dir / "admin.json"
    monkeypatch.setattr(admin_secret, "ADMIN_SECRET_FILE", admin_file)
    monkeypatch.setattr(secret_box, "SECRET_KEY_FILE", temp_dir / "settings.key")
    monkeypatch.setattr(Base.metadata, "create_all", lambda *args, **kwargs: None)

    password = "setup-secret"
    salt = secrets.token_bytes(16)
    derived_key = hashlib.scrypt(password.encode("utf-8"), salt=salt, n=16384, r=8, p=1, dklen=64)
    admin_file.write_text(
        json.dumps(
            {
                "algorithm": "scrypt",
                "username": "setup-admin",
                "salt": salt.hex(),
                "derived_key": derived_key.hex(),
                "key_length": 64,
                "N": 16384,
                "r": 8,
                "p": 1,
            }
        ),
        encoding="utf-8",
    )

    with build_session(temp_dir / "settings.db") as db:
        service = SettingsService(db)
        snapshot = service.get_settings_snapshot()
        secrets_row = db.get(SystemSettingSecret, "default")

        assert snapshot.adminForm.adminPasswordConfigured is True
        assert secrets_row is not None
        assert secrets_row.admin_password_hash.startswith("scrypt$")
        assert service.verify_admin_login("setup-admin", password) is not None