from __future__ import annotations

from pathlib import Path

import pytest
from PySide6.QtGui import QUndoCommand
from PySide6.QtWidgets import QApplication

from bedit_gui.controllers.document_controller import DocumentController
from bedit_gui.documents import Document
from bedit_gui.views.dialogs.document_dialogs import SaveChangesChoice
from bedit_gui.views.main_window import MainWindow


class FakeDialogs:
    def __init__(self) -> None:
        self.open_path: Path | None = None
        self.save_path: Path | None = None
        self.save_choice = SaveChangesChoice.CANCEL
        self.errors: list[tuple[str, Exception]] = []

    def choose_open_path(self, _current_path: Path | None) -> Path | None:
        return self.open_path

    def choose_save_path(self, _current_path: Path | None) -> Path | None:
        return self.save_path

    def ask_save_changes(self) -> SaveChangesChoice:
        return self.save_choice

    def show_file_error(self, title: str, error: Exception) -> None:
        self.errors.append((title, error))


@pytest.fixture(scope="module")
def qt_app() -> QApplication:
    return QApplication.instance() or QApplication([])


@pytest.mark.unit
def test_new_document_respects_unsaved_changes(qt_app: QApplication) -> None:
    document = Document(qt_app)
    window = MainWindow()
    dialogs = FakeDialogs()
    controller = DocumentController(document, window, dialogs)
    original_id = document.model.id
    document.undo_stack.push(QUndoCommand("change"))

    controller.new_document()
    assert document.model.id == original_id

    dialogs.save_choice = SaveChangesChoice.DISCARD
    controller.new_document()
    assert document.model.id != original_id
    assert not document.modified


@pytest.mark.unit
def test_save_as_then_open_document(
    qt_app: QApplication,
    tmp_path: Path,
) -> None:
    document = Document(qt_app)
    window = MainWindow()
    dialogs = FakeDialogs()
    controller = DocumentController(document, window, dialogs)
    original_id = document.model.id
    path = tmp_path / "document.json"

    dialogs.save_path = path
    assert controller.save_document_as()

    document.new()
    dialogs.open_path = path
    controller.open_document()

    assert document.model.id == original_id
    assert document.path == path
    assert not dialogs.errors