"""Tests for CreateCommentUseCase.

This module tests comment creation use case covering top-level comments,
replies to existing comments, and post-not-found scenarios.
"""

from unittest.mock import AsyncMock, Mock
from uuid import uuid4

import pytest

from app.application.use_cases.create_comment import CreateCommentUseCase
from app.domain.entities import Post
from app.domain.exceptions import NotFoundException


@pytest.fixture
def test_post() -> Post:
    """Create a test post for comment tests."""
    return Post.create(
        title_str="Commentable Post",
        content_str="This post will receive comments. Enough length here.",
        author_id="user-123",
        tags=["test"],
    )


class TestCreateCommentUseCase:
    """Tests for CreateCommentUseCase.

    Covers TC-UNIT-832 through TC-UNIT-834.
    """

    @pytest.mark.asyncio
    async def test_create_comment_on_post(
        self,
        mock_post_repository: Mock,
        mock_transaction_manager: Mock,
        test_post: Post,
    ) -> None:
        """Test creating a top-level comment on a post.

        TC-UNIT-832: Positive — create top-level comment.
        """
        mock_comment_repository = AsyncMock()
        mock_post_repository.get_by_id = AsyncMock(return_value=test_post)

        use_case = CreateCommentUseCase(
            post_repo=mock_post_repository,
            comment_repo=mock_comment_repository,
            tx_manager=mock_transaction_manager,
        )

        result = await use_case.execute(
            post_id=test_post.id,
            author_id="user-456",
            content="Great post! Thanks for sharing.",
        )

        assert result.post_id == test_post.id
        assert result.author_id == "user-456"
        assert result.content == "Great post! Thanks for sharing."
        assert result.parent_id is None
        assert result.like_count == 0
        mock_comment_repository.add.assert_called_once()
        mock_transaction_manager.commit.assert_called_once()

    @pytest.mark.asyncio
    async def test_create_comment_reply(
        self,
        mock_post_repository: Mock,
        mock_transaction_manager: Mock,
        test_post: Post,
    ) -> None:
        """Test creating a reply to an existing comment.

        TC-UNIT-833: Positive — reply to comment with parent_id.
        """
        mock_comment_repository = AsyncMock()
        mock_post_repository.get_by_id = AsyncMock(return_value=test_post)
        parent_id = uuid4()

        use_case = CreateCommentUseCase(
            post_repo=mock_post_repository,
            comment_repo=mock_comment_repository,
            tx_manager=mock_transaction_manager,
        )

        result = await use_case.execute(
            post_id=test_post.id,
            author_id="user-456",
            content="This is a reply.",
            parent_id=parent_id,
        )

        assert result.parent_id == parent_id
        assert result.post_id == test_post.id
        mock_comment_repository.add.assert_called_once()
        mock_transaction_manager.commit.assert_called_once()

    @pytest.mark.asyncio
    async def test_create_comment_post_not_found(
        self,
        mock_post_repository: Mock,
        mock_transaction_manager: Mock,
    ) -> None:
        """Test creating a comment on a non-existent post.

        TC-UNIT-834: Negative — post not found.
        """
        mock_comment_repository = AsyncMock()
        mock_post_repository.get_by_id = AsyncMock(return_value=None)

        use_case = CreateCommentUseCase(
            post_repo=mock_post_repository,
            comment_repo=mock_comment_repository,
            tx_manager=mock_transaction_manager,
        )

        with pytest.raises(NotFoundException):
            await use_case.execute(
                post_id=uuid4(),
                author_id="user-456",
                content="Comment on missing post.",
            )

        mock_comment_repository.add.assert_not_called()
        mock_transaction_manager.commit.assert_not_called()