"""
Unit tests for the resume tracker module.

Tests cover resume state tracking and loading.
"""

import sys
from unittest.mock import Mock
from pathlib import Path
import json
import tempfile

# Mock torch and transformers before importing
sys_mock = Mock()
sys.modules["torch"] = sys_mock
sys.modules["transformers"] = sys_mock

import pytest

from src.translator.resume_tracker import ResumeTracker, ResumeState


class TestResumeState:
    """Test cases for ResumeState dataclass."""

    def test_create_resume_state(self):
        """Test creating a resume state."""
        state = ResumeState(
            work_id="test_work",
            last_completed_index=10,
            last_failed_index=None,
            total_chapters=100,
        )

        assert state.work_id == "test_work"
        assert state.last_completed_index == 10
        assert state.last_failed_index is None
        assert state.total_chapters == 100

    def test_to_dict(self):
        """Test converting resume state to dictionary."""
        state = ResumeState(
            work_id="test_work",
            last_completed_index=10,
            last_failed_index=None,
            total_chapters=100,
            resume_message="Test message",
        )

        data = state.to_dict()

        assert data["work_id"] == "test_work"
        assert data["last_completed_index"] == 10
        assert data["last_failed_index"] is None
        assert data["total_chapters"] == 100
        assert data["resume_message"] == "Test message"
        assert "timestamp" in data

    def test_from_dict(self):
        """Test creating resume state from dictionary."""
        data = {
            "work_id": "test_work",
            "last_completed_index": 10,
            "last_failed_index": None,
            "total_chapters": 100,
            "timestamp": "2024-01-01T00:00:00",
            "resume_message": "Test message",
        }

        state = ResumeState.from_dict(data)

        assert state.work_id == "test_work"
        assert state.last_completed_index == 10
        assert state.total_chapters == 100

    def test_get_resume_index_with_failure(self):
        """Test getting resume index when there's a failed chapter."""
        state = ResumeState(
            work_id="test_work",
            last_completed_index=10,
            last_failed_index=15,
            total_chapters=100,
        )

        assert state.get_resume_index() == 15

    def test_get_resume_index_without_failure(self):
        """Test getting resume index when there's no failed chapter."""
        state = ResumeState(
            work_id="test_work",
            last_completed_index=10,
            last_failed_index=None,
            total_chapters=100,
        )

        assert state.get_resume_index() == 11

    def test_is_resumable_with_remaining(self):
        """Test is_resumable when there are remaining chapters."""
        state = ResumeState(
            work_id="test_work",
            last_completed_index=10,
            last_failed_index=None,
            total_chapters=100,
        )

        assert state.is_resumable() is True

    def test_is_resumable_complete(self):
        """Test is_resumable when all chapters are complete."""
        state = ResumeState(
            work_id="test_work",
            last_completed_index=99,
            last_failed_index=None,
            total_chapters=100,
        )

        assert state.is_resumable() is False


class TestResumeTracker:
    """Test cases for ResumeTracker class."""

    @pytest.fixture
    def temp_dir(self):
        """Create a temporary directory for testing."""
        with tempfile.TemporaryDirectory() as tmp:
            yield Path(tmp)

    @pytest.fixture
    def tracker(self, temp_dir):
        """Create a resume tracker for testing."""
        return ResumeTracker(temp_dir)

    def test_init(self, temp_dir):
        """Test ResumeTracker initialization."""
        tracker = ResumeTracker(temp_dir)

        assert tracker.storage_dir == temp_dir
        assert tracker.resume_dir == temp_dir / "resume"
        assert tracker.resume_dir.exists()

    def test_save_resume_state(self, tracker):
        """Test saving resume state."""
        state = tracker.save_resume_state(
            work_id="test_work",
            last_completed_index=10,
            last_failed_index=None,
            total_chapters=100,
        )

        assert state.work_id == "test_work"
        assert state.last_completed_index == 10
        assert "Resume from chapter" in state.resume_message

        # Check file was created
        resume_file = tracker._get_resume_file_path("test_work")
        assert resume_file.exists()

    def test_load_resume_state(self, tracker):
        """Test loading resume state."""
        # Save state first
        tracker.save_resume_state(
            work_id="test_work",
            last_completed_index=10,
            last_failed_index=None,
            total_chapters=100,
        )

        # Load it back
        loaded = tracker.load_resume_state("test_work")

        assert loaded is not None
        assert loaded.work_id == "test_work"
        assert loaded.last_completed_index == 10
        assert loaded.total_chapters == 100

    def test_load_nonexistent_resume_state(self, tracker):
        """Test loading a non-existent resume state."""
        loaded = tracker.load_resume_state("nonexistent")
        assert loaded is None

    def test_delete_resume_state(self, tracker):
        """Test deleting resume state."""
        # Save state first
        tracker.save_resume_state(
            work_id="test_work",
            last_completed_index=10,
            last_failed_index=None,
            total_chapters=100,
        )

        # Delete it
        tracker.delete_resume_state("test_work")

        # Check it's gone
        resume_file = tracker._get_resume_file_path("test_work")
        assert not resume_file.exists()

    def test_get_resume_index(self, tracker):
        """Test getting resume index."""
        # Save state first
        tracker.save_resume_state(
            work_id="test_work",
            last_completed_index=10,
            last_failed_index=None,
            total_chapters=100,
        )

        # Get resume index
        index = tracker.get_resume_index("test_work", 100)

        assert index == 11

    def test_get_resume_index_nonexistent(self, tracker):
        """Test getting resume index for non-existent state."""
        index = tracker.get_resume_index("nonexistent", 100)
        assert index is None

    def test_update_on_chapter_complete(self, tracker):
        """Test updating state on chapter completion."""
        tracker.update_on_chapter_complete(
            work_id="test_work",
            chapter_index=5,
            total_chapters=100,
        )

        loaded = tracker.load_resume_state("test_work")
        assert loaded is not None
        assert loaded.last_completed_index == 5
        assert loaded.last_failed_index is None

    def test_update_on_chapter_failed(self, tracker):
        """Test updating state on chapter failure."""
        tracker.update_on_chapter_failed(
            work_id="test_work",
            chapter_index=5,
            total_chapters=100,
        )

        loaded = tracker.load_resume_state("test_work")
        assert loaded is not None
        assert loaded.last_failed_index == 5

    def test_generate_resume_message_with_failure(self):
        """Test generating resume message with failed chapter."""
        state = ResumeState(
            work_id="test_work",
            last_completed_index=10,
            last_failed_index=15,
            total_chapters=100,
        )

        tracker = ResumeTracker(Path("/tmp"))
        message = tracker._generate_resume_message(state)

        assert "failed chapter 15" in message
        assert "85" in message  # remaining chapters

    def test_generate_resume_message_without_failure(self):
        """Test generating resume message without failed chapter."""
        state = ResumeState(
            work_id="test_work",
            last_completed_index=10,
            last_failed_index=None,
            total_chapters=100,
        )

        tracker = ResumeTracker(Path("/tmp"))
        message = tracker._generate_resume_message(state)

        assert "Resume from chapter 11" in message
        assert "89" in message  # remaining chapters

    def test_get_all_resume_states(self, tracker):
        """Test getting all resume states."""
        # Save multiple states
        tracker.save_resume_state("work1", 10, None, 100)
        tracker.save_resume_state("work2", 20, None, 200)

        states = tracker.get_all_resume_states()

        assert len(states) == 2
        work_ids = {s.work_id for s in states}
        assert work_ids == {"work1", "work2"}

    def test_clear_all_resume_states(self, tracker):
        """Test clearing all resume states."""
        # Save multiple states
        tracker.save_resume_state("work1", 10, None, 100)
        tracker.save_resume_state("work2", 20, None, 200)

        tracker.clear_all_resume_states()

        states = tracker.get_all_resume_states()
        assert len(states) == 0

    def test_update_existing_state_on_complete(self, tracker):
        """Test that updating state preserves existing data."""
        # Save initial state
        tracker.save_resume_state(
            work_id="test_work",
            last_completed_index=5,
            last_failed_index=7,
            total_chapters=100,
        )

        # Update on completion
        tracker.update_on_chapter_complete(
            work_id="test_work",
            chapter_index=10,
            total_chapters=100,
        )

        loaded = tracker.load_resume_state("test_work")
        assert loaded.last_completed_index == 10
        assert loaded.last_failed_index is None  # Should be cleared

    def test_custom_resume_message(self, tracker):
        """Test saving state with custom resume message."""
        state = tracker.save_resume_state(
            work_id="test_work",
            last_completed_index=10,
            last_failed_index=None,
            total_chapters=100,
            resume_message="Custom message here",
        )

        assert state.resume_message == "Custom message here"

    def test_get_resume_file_path(self, tracker):
        """Test getting resume file path."""
        path = tracker._get_resume_file_path("test_work")

        assert path.name == "test_work_resume.json"
        assert path.parent == tracker.resume_dir