#!/usr/bin/env python3
"""
Comprehensive test for bounds checking fixes in crossword generator.
"""

import asyncio
import sys
import pytest
from pathlib import Path

# Add project root to path
project_root = Path(__file__).parent.parent  # Go up from test-integration to backend-py
sys.path.insert(0, str(project_root))

from src.services.crossword_generator_fixed import CrosswordGeneratorFixed

class TestBoundsChecking:
    """Test all bounds checking in crossword generator."""
    
    def setup_method(self):
        """Setup test instance."""
        self.generator = CrosswordGeneratorFixed(vector_service=None)
    
    def test_can_place_word_bounds_horizontal(self):
        """Test _can_place_word bounds checking for horizontal placement."""
        # Create small grid
        grid = [["." for _ in range(5)] for _ in range(5)]
        
        # Test cases that should fail bounds checking
        assert not self.generator._can_place_word(grid, "TOOLONG", 2, 1, "horizontal")  # Word too long
        assert not self.generator._can_place_word(grid, "TEST", -1, 1, "horizontal")    # Negative row
        assert not self.generator._can_place_word(grid, "TEST", 1, -1, "horizontal")    # Negative col
        assert not self.generator._can_place_word(grid, "TEST", 5, 1, "horizontal")     # Row >= size
        assert not self.generator._can_place_word(grid, "TEST", 1, 5, "horizontal")     # Col >= size
        assert not self.generator._can_place_word(grid, "TEST", 1, 3, "horizontal")     # Word extends beyond grid
        
        # Test cases that should pass
        assert self.generator._can_place_word(grid, "TEST", 2, 1, "horizontal")         # Valid placement
        assert self.generator._can_place_word(grid, "A", 0, 0, "horizontal")            # Single letter
        
    def test_can_place_word_bounds_vertical(self):
        """Test _can_place_word bounds checking for vertical placement."""
        # Create small grid
        grid = [["." for _ in range(5)] for _ in range(5)]
        
        # Test cases that should fail bounds checking
        assert not self.generator._can_place_word(grid, "TOOLONG", 1, 2, "vertical")    # Word too long
        assert not self.generator._can_place_word(grid, "TEST", -1, 1, "vertical")      # Negative row
        assert not self.generator._can_place_word(grid, "TEST", 1, -1, "vertical")      # Negative col
        assert not self.generator._can_place_word(grid, "TEST", 5, 1, "vertical")       # Row >= size
        assert not self.generator._can_place_word(grid, "TEST", 1, 5, "vertical")       # Col >= size
        assert not self.generator._can_place_word(grid, "TEST", 3, 1, "vertical")       # Word extends beyond grid
        
        # Test cases that should pass
        assert self.generator._can_place_word(grid, "TEST", 1, 2, "vertical")           # Valid placement
        assert self.generator._can_place_word(grid, "A", 0, 0, "vertical")              # Single letter
    
    def test_place_word_bounds_horizontal(self):
        """Test _place_word bounds checking for horizontal placement."""
        grid = [["." for _ in range(5)] for _ in range(5)]
        
        # Valid placement should work
        original_state = self.generator._place_word(grid, "TEST", 2, 1, "horizontal")
        assert len(original_state) == 4
        assert grid[2][1] == "T"
        assert grid[2][4] == "T"
        
        # Test out-of-bounds placement should raise IndexError
        with pytest.raises(IndexError):
            self.generator._place_word(grid, "TOOLONG", 2, 1, "horizontal")
        
        with pytest.raises(IndexError):
            self.generator._place_word(grid, "TEST", -1, 1, "horizontal")
        
        with pytest.raises(IndexError):
            self.generator._place_word(grid, "TEST", 5, 1, "horizontal")
            
        with pytest.raises(IndexError):
            self.generator._place_word(grid, "TEST", 1, 5, "horizontal")
    
    def test_place_word_bounds_vertical(self):
        """Test _place_word bounds checking for vertical placement."""
        grid = [["." for _ in range(5)] for _ in range(5)]
        
        # Valid placement should work
        original_state = self.generator._place_word(grid, "TEST", 1, 2, "vertical")
        assert len(original_state) == 4
        assert grid[1][2] == "T"
        assert grid[4][2] == "T"
        
        # Test out-of-bounds placement should raise IndexError
        with pytest.raises(IndexError):
            self.generator._place_word(grid, "TOOLONG", 1, 2, "vertical")
            
        with pytest.raises(IndexError):
            self.generator._place_word(grid, "TEST", -1, 2, "vertical")
            
        with pytest.raises(IndexError):
            self.generator._place_word(grid, "TEST", 5, 2, "vertical")
            
        with pytest.raises(IndexError):
            self.generator._place_word(grid, "TEST", 2, 5, "vertical")
    
    def test_remove_word_bounds(self):
        """Test _remove_word bounds checking."""
        grid = [["." for _ in range(5)] for _ in range(5)]
        
        # Place a word first
        original_state = self.generator._place_word(grid, "TEST", 2, 1, "horizontal")
        
        # Normal removal should work
        self.generator._remove_word(grid, original_state)
        assert grid[2][1] == "."
        
        # Test invalid original state should raise IndexError
        bad_state = [{"row": -1, "col": 1, "value": "."}]
        with pytest.raises(IndexError):
            self.generator._remove_word(grid, bad_state)
            
        bad_state = [{"row": 5, "col": 1, "value": "."}]
        with pytest.raises(IndexError):
            self.generator._remove_word(grid, bad_state)
            
        bad_state = [{"row": 1, "col": -1, "value": "."}]
        with pytest.raises(IndexError):
            self.generator._remove_word(grid, bad_state)
            
        bad_state = [{"row": 1, "col": 5, "value": "."}]
        with pytest.raises(IndexError):
            self.generator._remove_word(grid, bad_state)
    
    def test_create_simple_cross_bounds(self):
        """Test _create_simple_cross bounds checking."""
        # Test with words that have intersections
        word_list = ["CAT", "TOY"]  # 'T' intersection
        word_objs = [{"word": w, "clue": f"Clue for {w}"} for w in word_list]
        
        # This should work without bounds errors
        result = self.generator._create_simple_cross(word_list, word_objs)
        assert result is not None
        assert len(result["placed_words"]) == 2
        
        # Test with words that might cause issues
        word_list = ["A", "A"]  # Same single letter
        word_objs = [{"word": w, "clue": f"Clue for {w}"} for w in word_list]
        
        # This should not crash with bounds errors
        result = self.generator._create_simple_cross(word_list, word_objs)
        # May return None due to placement issues, but should not crash
    
    def test_trim_grid_bounds(self):
        """Test _trim_grid bounds checking."""
        # Create a grid with words placed
        grid = [["." for _ in range(10)] for _ in range(10)]
        
        # Place some letters
        grid[5][3] = "T"
        grid[5][4] = "E"
        grid[5][5] = "S"
        grid[5][6] = "T"
        
        placed_words = [{
            "word": "TEST",
            "row": 5,
            "col": 3,
            "direction": "horizontal",
            "number": 1
        }]
        
        # This should work without bounds errors
        result = self.generator._trim_grid(grid, placed_words)
        assert result is not None
        assert "grid" in result
        assert "placed_words" in result
        
        # Test with edge case placements
        placed_words = [{
            "word": "A",
            "row": 0,
            "col": 0,
            "direction": "horizontal", 
            "number": 1
        }]
        
        grid[0][0] = "A"
        result = self.generator._trim_grid(grid, placed_words)
        assert result is not None
    
    def test_calculation_placement_score_bounds(self):
        """Test _calculate_placement_score bounds checking."""
        grid = [["." for _ in range(5)] for _ in range(5)]
        
        # Place some letters for intersection testing
        grid[2][2] = "T"
        grid[2][3] = "E"
        
        placement = {"row": 2, "col": 2, "direction": "horizontal"}
        placed_words = []
        
        # This should work without bounds errors
        score = self.generator._calculate_placement_score(grid, "TEST", placement, placed_words)
        assert isinstance(score, int)
        
        # Test with out-of-bounds placement (should handle gracefully)
        placement = {"row": 4, "col": 3, "direction": "horizontal"}  # Would extend beyond grid
        score = self.generator._calculate_placement_score(grid, "TEST", placement, placed_words)
        assert isinstance(score, int)
        
        # Test with negative placement (should handle gracefully)
        placement = {"row": -1, "col": 0, "direction": "horizontal"}
        score = self.generator._calculate_placement_score(grid, "TEST", placement, placed_words)
        assert isinstance(score, int)

async def test_full_generation_stress():
    """Stress test full generation to catch index errors."""
    generator = CrosswordGeneratorFixed(vector_service=None)
    
    # Mock word selection to return test words
    test_words = [
        {"word": "CAT", "clue": "Feline pet"},
        {"word": "DOG", "clue": "Man's best friend"}, 
        {"word": "BIRD", "clue": "Flying animal"},
        {"word": "FISH", "clue": "Aquatic animal"},
        {"word": "ELEPHANT", "clue": "Large mammal"},
        {"word": "TIGER", "clue": "Striped cat"},
        {"word": "HORSE", "clue": "Riding animal"},
        {"word": "BEAR", "clue": "Large carnivore"},
        {"word": "WOLF", "clue": "Pack animal"},
        {"word": "LION", "clue": "King of jungle"}
    ]
    
    generator._select_words = lambda topics, difficulty, use_ai: test_words
    
    # Run multiple generation attempts
    for i in range(20):
        try:
            result = await generator.generate_puzzle(["animals"], "medium", use_ai=False)
            if result:
                print(f"✅ Generation {i+1} succeeded")
            else:
                print(f"⚠️ Generation {i+1} returned None")
        except IndexError as e:
            print(f"❌ Index error in generation {i+1}: {e}")
            raise
        except Exception as e:
            print(f"⚠️ Other error in generation {i+1}: {e}")
            # Don't raise for other errors, just continue
    
    print("✅ All stress test generations completed without index errors!")

if __name__ == "__main__":
    # Run tests
    print("🧪 Running comprehensive bounds checking tests...")
    
    # Run pytest on this file
    import subprocess
    result = subprocess.run([sys.executable, "-m", "pytest", __file__, "-v"], 
                          capture_output=True, text=True)
    
    print("STDOUT:", result.stdout)
    if result.stderr:
        print("STDERR:", result.stderr)
    
    # Run stress test
    print("\n🏋️ Running stress test...")
    asyncio.run(test_full_generation_stress())