from __future__ import annotations

import hashlib
import inspect
import sqlite3
from pathlib import Path

import pytest

from jarca_ledger_mcp.application import account_valuation_service as valuation
from jarca_ledger_mcp.application import (
    assets_service,
    categorization_services,
    cross_transfer_service,
    reconciliation_service,
    system_services,
)
from jarca_ledger_mcp.infrastructure.sqlite import connection


def _sha256(path: Path) -> str:
    return hashlib.sha256(path.read_bytes()).hexdigest()


def test_read_queries_missing_nested_db_return_stable_error_without_creating_path(tmp_path):
    db_path = tmp_path / "missing" / "nested" / "ledger.sqlite3"
    calls = [
        lambda: system_services.list_ledger_accounts(db_path=str(db_path)),
        lambda: valuation.list_account_valuations("account", db_path=str(db_path)),
        lambda: assets_service.list_manual_assets(db_path=str(db_path)),
        lambda: assets_service.preview_asset_snapshot_close(db_path=str(db_path)),
        lambda: reconciliation_service.get_balance_reconciliation_report(db_path=str(db_path)),
    ]

    for read in calls:
        result = read()
        assert result["success"] is False
        assert result["error_code"] == "db_not_initialized"
        assert result["error"]
    assert not db_path.exists()
    assert not db_path.parent.exists()


def test_read_only_connection_rejects_writes_and_does_not_commit(tmp_path):
    db_path = tmp_path / "ledger.sqlite3"
    system_services.create_ledger_account("checking", db_path=str(db_path))  # first-use writer initializes
    before = _sha256(db_path)

    with connection.read_db(str(db_path)) as conn:
        with pytest.raises(sqlite3.OperationalError):
            conn.execute("INSERT INTO accounts (id, name, type) VALUES ('x', 'x', 'bank')")

    assert _sha256(db_path) == before


def test_read_suite_does_not_initialize_or_change_initialized_database(tmp_path, monkeypatch):
    db_path = tmp_path / "ledger.sqlite3"
    system_services.create_ledger_account("checking", db_path=str(db_path))
    before = _sha256(db_path)
    def fail_init(*args, **kwargs):
        raise AssertionError("read path called init_db")

    monkeypatch.setattr("jarca_ledger_mcp.infrastructure.sqlite.migrations.init_db", fail_init)
    monkeypatch.setattr("jarca_ledger_mcp.infrastructure.sqlite.connection.init_db", fail_init, raising=False)
    reads = [
        lambda: system_services.list_ledger_accounts(db_path=str(db_path)),
        lambda: valuation.list_account_valuations("account", db_path=str(db_path)),
        lambda: assets_service.list_manual_assets(db_path=str(db_path)),
        lambda: assets_service.preview_asset_snapshot_close(db_path=str(db_path)),
        lambda: reconciliation_service.get_balance_reconciliation_report(db_path=str(db_path)),
    ]
    for read in reads:
        assert read()["success"] is True
    assert _sha256(db_path) == before


def test_first_use_writer_still_initializes_database(tmp_path):
    db_path = tmp_path / "new" / "ledger.sqlite3"
    result = system_services.create_ledger_account("checking", db_path=str(db_path))
    assert result["success"] is True
    assert db_path.is_file()


def test_read_schema_error_is_not_misreported_as_uninitialized(tmp_path):
    db_path = tmp_path / "empty.sqlite3"
    sqlite3.connect(db_path).close()

    result = system_services.list_ledger_accounts(db_path=str(db_path))

    assert result["success"] is False
    assert result["error_code"] == "db_error"


def test_nested_categorization_preview_propagates_missing_db_envelope(tmp_path):
    db_path = tmp_path / "missing" / "ledger.sqlite3"

    result = categorization_services.preview_categorization(db_path=str(db_path))

    assert result["success"] is False
    assert result["error_code"] == "db_not_initialized"
    assert not db_path.parent.exists()


def test_public_read_signatures_remain_positional_compatible():
    assert list(inspect.signature(valuation.list_account_valuations).parameters)[:2] == ["account_id", "include_rejected"]
    assert list(inspect.signature(assets_service.preview_asset_snapshot_close).parameters)[:2] == ["basis_date", "db_path"]
    assert list(inspect.signature(reconciliation_service.get_balance_reconciliation_report).parameters)[:2] == ["account_id", "baseline_balance"]


def test_preview_categorization_initialized_db_preserves_success_envelope(tmp_path):
    db_path = tmp_path / "ledger.sqlite3"
    system_services.create_ledger_account("checking", db_path=str(db_path))
    result = categorization_services.preview_categorization(db_path=str(db_path))
    assert result["success"] is True
    assert result["matched_count"] == 0
    assert result["unmatched_count"] == 0


def test_apply_categorization_rules_missing_db_initializes_writer_or_returns_stable_error(tmp_path):
    db_path = tmp_path / "nested" / "ledger.sqlite3"
    result = categorization_services.apply_categorization_rules(db_path=str(db_path))
    assert result["success"] is True
    assert result["preview"]["matched_count"] == 0


def test_cross_transfer_review_queue_missing_nested_db_returns_stable_error_without_creating_path(tmp_path):
    db_path = tmp_path / "missing" / "nested" / "ledger.sqlite3"

    result = cross_transfer_service.list_cross_transfer_review_queue(db_path=str(db_path))

    assert result["success"] is False
    assert result["error_code"] == "db_not_initialized"
    assert result["error"]
    assert not db_path.exists()
    assert not db_path.parent.exists()


def test_cross_transfer_preview_missing_nested_db_returns_stable_error_without_creating_path(tmp_path):
    db_path = tmp_path / "missing" / "nested" / "ledger.sqlite3"

    result = cross_transfer_service.preview_cross_account_transfers(db_path=str(db_path))

    assert result["success"] is False
    assert result["error_code"] == "db_not_initialized"
    assert result["error"]
    assert not db_path.exists()
    assert not db_path.parent.exists()


def test_cross_transfer_read_paths_do_not_initialize_or_mutate_initialized_db(tmp_path, monkeypatch):
    db_path = tmp_path / "ledger.sqlite3"
    system_services.create_ledger_account("checking", db_path=str(db_path))
    before = _sha256(db_path)

    def fail_init(*args, **kwargs):
        raise AssertionError("cross-transfer read path called init_db")

    monkeypatch.setattr("jarca_ledger_mcp.infrastructure.sqlite.migrations.init_db", fail_init)
    monkeypatch.setattr("jarca_ledger_mcp.infrastructure.sqlite.connection.init_db", fail_init, raising=False)

    queue = cross_transfer_service.list_cross_transfer_review_queue(db_path=str(db_path))
    preview = cross_transfer_service.preview_cross_account_transfers(db_path=str(db_path))

    assert queue["success"] is True
    assert preview["success"] is True
    assert _sha256(db_path) == before