import sys
from pathlib import Path

sys.path.insert(0, str(Path(__file__).parent.parent / "src"))

import pytest
import hmac
from unittest.mock import Mock, MagicMock, patch


class TestCheckPassword:
    """Tests for check_password function."""
    
    @patch("app.st")
    def test_returns_true_when_already_authenticated(self, mock_st):
        """Should return True if password_correct is True."""
        from app import check_password
        
        mock_st.session_state = MagicMock()
        mock_st.session_state.__contains__ = Mock(return_value=True)
        mock_st.session_state.password_correct = True
        
        result = check_password()
        
        assert result is True
    
    @patch("app.APP_PASSWORD", "")
    @patch("app.st")
    def test_returns_true_when_no_password_configured(self, mock_st):
        """Should return True when APP_PASSWORD is empty."""
        from app import check_password
        
        mock_st.session_state = MagicMock()
        mock_st.session_state.__contains__ = Mock(return_value=False)
        
        result = check_password()
        
        assert result is True
    
    @patch("app.APP_PASSWORD", "correct")
    @patch("app.st")
    def test_returns_false_when_wrong_password(self, mock_st):
        """Should return False for wrong password."""
        from app import check_password
        
        mock_st.session_state = MagicMock()
        mock_st.session_state.__contains__ = Mock(return_value=False)
        mock_st.text_input.return_value = "wrong"
        
        result = check_password()
        
        assert result is False
        mock_st.error.assert_called_once()
    
    @patch("app.APP_PASSWORD", "correct")
    @patch("app.st")
    def test_returns_false_when_no_password_entered(self, mock_st):
        """Should return False when no password entered."""
        from app import check_password
        
        mock_st.session_state = MagicMock()
        mock_st.session_state.__contains__ = Mock(return_value=False)
        mock_st.text_input.return_value = ""
        
        result = check_password()
        
        assert result is False


class TestProcessUploadedFiles:
    """Tests for process_uploaded_files function."""
    
    @patch("app.get_vector_store")
    @patch("app.extract_pdf_pages")
    @patch("app.process_documents")
    @patch("app.chunks_to_store_format")
    def test_processes_single_file(self, mock_format, mock_process, mock_extract, mock_get_store):
        """Should process a single PDF file."""
        from app import process_uploaded_files
        
        mock_file = Mock()
        mock_file.name = "test.pdf"
        
        mock_extract.return_value = [{"text": "content", "page_number": 1, "source": "test.pdf"}]
        mock_process.return_value = [{"text": "chunk", "metadata": {}}]
        mock_format.return_value = (["chunk"], [{}])
        
        mock_store = Mock()
        mock_store.get_loaded_sources.return_value = set()
        mock_get_store.return_value = mock_store
        
        result = process_uploaded_files([mock_file])
        
        assert result == 1
        mock_store.add_documents.assert_called_once()
    
    @patch("app.get_vector_store")
    @patch("app.extract_pdf_pages")
    @patch("app.process_documents")
    @patch("app.chunks_to_store_format")
    def test_processes_multiple_files(self, mock_format, mock_process, mock_extract, mock_get_store):
        """Should process multiple PDF files."""
        from app import process_uploaded_files
        
        mock_file1 = Mock()
        mock_file1.name = "test1.pdf"
        mock_file2 = Mock()
        mock_file2.name = "test2.pdf"
        
        mock_extract.return_value = [{"text": "content", "page_number": 1, "source": "test.pdf"}]
        mock_process.return_value = [{"text": "chunk", "metadata": {}}]
        mock_format.return_value = (["chunk"], [{}])
        
        mock_store = Mock()
        mock_store.get_loaded_sources.return_value = set()
        mock_get_store.return_value = mock_store
        
        result = process_uploaded_files([mock_file1, mock_file2])
        
        assert result == 2
        assert mock_store.add_documents.call_count == 2
    
    def test_empty_files_returns_zero(self):
        """Should return 0 for empty file list."""
        from app import process_uploaded_files
        
        result = process_uploaded_files([])
        
        assert result == 0
    
    def test_none_files_returns_zero(self):
        """Should return 0 for None."""
        from app import process_uploaded_files
        
        result = process_uploaded_files(None)
        
        assert result == 0
    
    @patch("app.get_vector_store")
    @patch("app.extract_pdf_pages")
    @patch("app.process_documents")
    def test_skips_empty_chunks(self, mock_process, mock_extract, mock_get_store):
        """Should skip files with no chunks."""
        from app import process_uploaded_files
        
        mock_file = Mock()
        mock_file.name = "empty.pdf"
        
        mock_extract.return_value = []
        mock_process.return_value = []
        
        mock_store = Mock()
        mock_store.get_loaded_sources.return_value = set()
        mock_get_store.return_value = mock_store
        
        result = process_uploaded_files([mock_file])
        
        assert result == 0
        mock_store.add_documents.assert_not_called()


class TestResetApplication:
    """Tests for reset_application function."""
    
    @patch("app.reset_llm_generator")
    @patch("app.reset_retrieval_engine")
    @patch("app.reset_vector_store")
    @patch("app.reset_embedder")
    @patch("app.st")
    def test_resets_all_components(self, mock_st, mock_reset_embedder, mock_reset_store, mock_reset_retrieval, mock_reset_llm):
        """Should reset vector store and embedder."""
        from app import reset_application
        
        mock_st.session_state = MagicMock()
        
        reset_application()
        
        mock_reset_store.assert_called_once()
        mock_reset_embedder.assert_called_once()
        mock_reset_retrieval.assert_called_once()
        mock_reset_llm.assert_called_once()
    
    @patch("app.reset_llm_generator")
    @patch("app.reset_retrieval_engine")
    @patch("app.reset_vector_store")
    @patch("app.reset_embedder")
    @patch("app.st")
    def test_clears_session_state(self, mock_st, mock_reset_embedder, mock_reset_store, mock_reset_retrieval, mock_reset_llm):
        """Should clear session state values."""
        from app import reset_application
        
        mock_st.session_state = MagicMock()
        mock_st.session_state.documents_processed = True
        mock_st.session_state.chunk_count = 100
        mock_st.session_state.chat_history = [{"role": "user", "content": "hi"}]
        mock_st.session_state.sources = [{}]
        
        reset_application()
        
        assert mock_st.session_state.documents_processed is False
        assert mock_st.session_state.chunk_count == 0
        assert mock_st.session_state.chat_history == []
        assert mock_st.session_state.sources == []


class TestInitSessionState:
    """Tests for init_session_state function."""
    
    @patch("app.st")
    def test_initializes_missing_keys(self, mock_st):
        """Should initialize missing session state keys."""
        from app import init_session_state
        
        mock_st.session_state = {}
        
        init_session_state()
        
        assert "documents_processed" in mock_st.session_state
        assert "chunk_count" in mock_st.session_state
        assert "chat_history" in mock_st.session_state
        assert "selected_model" in mock_st.session_state
        assert "use_reranking" in mock_st.session_state
    
    @patch("app.st")
    def test_preserves_existing_values(self, mock_st):
        """Should not overwrite existing session state values."""
        from app import init_session_state
        
        mock_st.session_state = {"chunk_count": 50}
        
        init_session_state()
        
        assert mock_st.session_state["chunk_count"] == 50
    
    @patch("app.st")
    def test_default_values(self, mock_st):
        """Should set correct default values."""
        from app import init_session_state
        from config import DEFAULT_LLM_MODEL
        
        mock_st.session_state = {}
        
        init_session_state()
        
        assert mock_st.session_state["documents_processed"] is False
        assert mock_st.session_state["chunk_count"] == 0
        assert mock_st.session_state["chat_history"] == []
        assert mock_st.session_state["use_reranking"] is True
        assert mock_st.session_state["selected_model"] == DEFAULT_LLM_MODEL


class TestGenerateResponse:
    """Tests for generate_response function."""
    
    @pytest.fixture(autouse=True)
    def reset_handler(self):
        from src.integration.query_handler import reset_query_handler
        reset_query_handler()
        yield
        reset_query_handler()

    @patch("app.get_query_handler")
    def test_returns_response_sources_debug(self, mock_get_handler):
        from app import generate_response
        
        mock_handler = MagicMock()
        mock_result = MagicMock()
        mock_result.response = "response text"
        mock_result.sources = [{"source": "test.pdf"}]
        mock_result.mode.value = "documents"
        mock_result.execution_time = 0.5
        mock_result.intent = None
        mock_result.sql_query = None
        mock_result.db_results = None
        mock_result.success = True
        mock_result.error = None
        mock_result.routing_metadata = None
        mock_handler.execute.return_value = mock_result
        mock_get_handler.return_value = mock_handler
        
        response, sources, debug = generate_response("question", True, [], "model-id")
        
        assert response == "response text"
        assert sources == [{"source": "test.pdf"}]
        assert debug["success"] is True
    
    @patch("app.get_query_handler")
    def test_passes_reranking_flag(self, mock_get_handler):
        from app import generate_response
        
        mock_handler = MagicMock()
        mock_result = MagicMock()
        mock_result.response = ""
        mock_result.sources = []
        mock_result.mode.value = "documents"
        mock_result.execution_time = 0.1
        mock_result.intent = None
        mock_result.sql_query = None
        mock_result.db_results = None
        mock_result.success = True
        mock_result.error = None
        mock_result.routing_metadata = None
        mock_handler.execute.return_value = mock_result
        mock_get_handler.return_value = mock_handler
        
        generate_response("q", False, [], "model")
        
        mock_handler.execute.assert_called_once()
    
    @patch("app.get_query_handler")
    def test_passes_chat_history_to_retrieve(self, mock_get_handler):
        from app import generate_response
        
        mock_handler = MagicMock()
        mock_result = MagicMock()
        mock_result.response = ""
        mock_result.sources = []
        mock_result.mode.value = "documents"
        mock_result.execution_time = 0.1
        mock_result.intent = None
        mock_result.sql_query = None
        mock_result.db_results = None
        mock_result.success = True
        mock_result.error = None
        mock_result.routing_metadata = None
        mock_handler.execute.return_value = mock_result
        mock_get_handler.return_value = mock_handler
        
        history = [{"role": "user", "content": "Atlas nedir?"}]
        generate_response("Bunun ozellikleri?", True, history, "model")
        
        call_kwargs = mock_handler.execute.call_args
        assert call_kwargs[1]["chat_history"] == history
    
    @patch("app.get_query_handler")
    def test_limits_chat_history(self, mock_get_handler):
        from app import generate_response
        
        mock_handler = MagicMock()
        mock_result = MagicMock()
        mock_result.response = ""
        mock_result.sources = []
        mock_result.mode.value = "documents"
        mock_result.execution_time = 0.1
        mock_result.intent = None
        mock_result.sql_query = None
        mock_result.db_results = None
        mock_result.success = True
        mock_result.error = None
        mock_result.routing_metadata = None
        mock_handler.execute.return_value = mock_result
        mock_get_handler.return_value = mock_handler
        
        long_history = [{"role": "user", "content": f"msg{i}"} for i in range(10)]
        
        generate_response("q", True, long_history, "model")
        
        call_kwargs = mock_handler.execute.call_args
        assert call_kwargs[1]["chat_history"] == long_history
    
    @patch("app.get_query_handler")
    def test_passes_model_id(self, mock_get_handler):
        from app import generate_response
        
        mock_handler = MagicMock()
        mock_result = MagicMock()
        mock_result.response = ""
        mock_result.sources = []
        mock_result.mode.value = "documents"
        mock_result.execution_time = 0.1
        mock_result.intent = None
        mock_result.sql_query = None
        mock_result.db_results = None
        mock_result.success = True
        mock_result.error = None
        mock_result.routing_metadata = None
        mock_handler.execute.return_value = mock_result
        mock_get_handler.return_value = mock_handler
        
        generate_response("q", True, [], "custom-model")
        
        call_kwargs = mock_handler.execute.call_args
        assert call_kwargs[1]["model_id"] == "custom-model"


class TestLoadCss:
    """Tests for load_css function."""
    
    @patch("app.STYLES_PATH")
    def test_loads_css_from_file(self, mock_path):
        """Should load CSS content from file."""
        from app import load_css
        
        mock_path.exists.return_value = True
        mock_path.read_text.return_value = ".test { color: red; }"
        
        result = load_css()
        
        assert result == ".test { color: red; }"
    
    @patch("app.STYLES_PATH")
    def test_returns_empty_if_file_missing(self, mock_path):
        """Should return empty string if file doesn't exist."""
        from app import load_css
        
        mock_path.exists.return_value = False
        
        result = load_css()
        
        assert result == ""


class TestApplyCustomCss:
    """Tests for apply_custom_css function."""
    
    @patch("app.load_css")
    @patch("app.st")
    def test_calls_markdown_with_css(self, mock_st, mock_load):
        """Should inject CSS via st.markdown."""
        from app import apply_custom_css
        
        mock_load.return_value = ".test { color: red; }"
        
        apply_custom_css()
        
        mock_st.markdown.assert_called_once()
        call_args = mock_st.markdown.call_args
        assert "unsafe_allow_html" in call_args[1]
        assert call_args[1]["unsafe_allow_html"] is True
    
    @patch("app.load_css")
    @patch("app.st")
    def test_skips_if_no_css(self, mock_st, mock_load):
        """Should not call markdown if CSS is empty."""
        from app import apply_custom_css
        
        mock_load.return_value = ""
        
        apply_custom_css()
        
        mock_st.markdown.assert_not_called()
    
    @patch("app.load_css")
    @patch("app.st")
    def test_wraps_css_in_style_tags(self, mock_st, mock_load):
        """Should wrap CSS content in style tags."""
        from app import apply_custom_css
        
        mock_load.return_value = ".box { padding: 10px; }"
        
        apply_custom_css()
        
        call_args = mock_st.markdown.call_args[0][0]
        assert "<style>" in call_args
        assert "</style>" in call_args
        assert ".box { padding: 10px; }" in call_args


class TestGetBaseDocuments:
    """Tests for get_base_documents function."""
    
    @patch("app.BASE_DOCUMENTS_PATH")
    def test_returns_empty_if_path_not_exists(self, mock_path):
        """Should return empty list if documents folder doesn't exist."""
        from app import get_base_documents
        
        mock_path.exists.return_value = False
        
        result = get_base_documents()
        
        assert result == []
    
    @patch("app.BASE_DOCUMENTS_PATH")
    def test_returns_pdf_files(self, mock_path):
        """Should return list of PDF files."""
        from app import get_base_documents
        
        mock_path.exists.return_value = True
        mock_path.glob.return_value = [Path("/docs/a.pdf"), Path("/docs/b.pdf")]
        
        result = get_base_documents()
        
        assert len(result) == 2
        mock_path.glob.assert_called_with("*.pdf")


class TestLoadDefaultDocuments:
    """Tests for load_default_documents function."""
    
    @patch("app.get_base_documents")
    @patch("app.st")
    def test_skips_if_already_loaded(self, mock_st, mock_get_docs):
        """Should skip if base_docs_loaded is True."""
        from app import load_default_documents
        
        mock_st.session_state.get.return_value = True
        
        load_default_documents()
        
        mock_get_docs.assert_not_called()
    
    @patch("app.get_vector_store")
    @patch("app.get_base_documents")
    @patch("app.st")
    def test_skips_if_no_documents(self, mock_st, mock_get_docs, mock_get_store):
        """Should set flag and return if no documents."""
        from app import load_default_documents
        
        mock_st.session_state = MagicMock()
        mock_st.session_state.get.return_value = False
        mock_get_docs.return_value = []
        
        load_default_documents()
        
        assert mock_st.session_state.base_docs_loaded is True
    
    @patch("app.chunks_to_store_format")
    @patch("app.process_documents")
    @patch("app.extract_pdf_from_path")
    @patch("app.get_vector_store")
    @patch("app.get_base_documents")
    @patch("app.st")
    def test_processes_documents(
        self, mock_st, mock_get_docs, mock_get_store,
        mock_extract, mock_process, mock_format
    ):
        """Should process and store base documents."""
        from app import load_default_documents
        
        mock_st.session_state = MagicMock()
        mock_st.session_state.get.return_value = False
        mock_get_docs.return_value = [Path("/docs/test.pdf")]
        
        mock_store = MagicMock()
        mock_store.get_collection_stats.return_value = {"points_count": 0}
        mock_get_store.return_value = mock_store
        
        mock_extract.return_value = [{"text": "content", "page_number": 1, "source": "test.pdf"}]
        mock_process.return_value = [{"text": "chunk", "metadata": {}}]
        mock_format.return_value = (["chunk"], [{}])
        
        load_default_documents()
        
        mock_store.add_documents.assert_called_once()
        assert mock_st.session_state.base_docs_loaded is True
        assert mock_st.session_state.documents_processed is True


class TestRenderDebugInfo:
    """Tests for render_debug_info function."""
    
    @patch("app.st")
    def test_shows_query_rewriting_when_rewritten(self, mock_st):
        """Should display query rewriting section when query was rewritten."""
        from app import render_debug_info
        
        mock_col = MagicMock()
        mock_col.__enter__ = MagicMock(return_value=mock_col)
        mock_col.__exit__ = MagicMock(return_value=False)
        mock_st.columns.side_effect = [
            [mock_col, mock_col],
            [mock_col, mock_col, mock_col]
        ]
        
        debug_info = {
            "query": "Bunun ozellikleri?",
            "search_query": "Atlas ERP ozellikleri nelerdir?",
            "query_rewritten": True,
            "rewrite_info": {
                "is_follow_up": True,
                "method": "llm",
                "rewrite_time_ms": 150
            }
        }
        
        render_debug_info(debug_info)
        
        mock_st.subheader.assert_called()
        assert mock_st.columns.call_count == 2
    
    @patch("app.st")
    def test_skips_rewriting_section_when_not_rewritten(self, mock_st):
        """Should skip query rewriting section when query was not rewritten."""
        from app import render_debug_info
        
        debug_info = {
            "query": "Atlas nedir?",
            "search_query": "Atlas nedir?",
            "query_rewritten": False,
            "rewrite_info": None
        }
        
        render_debug_info(debug_info)
        
        mock_st.info.assert_not_called()
        mock_st.success.assert_not_called()
    
    @patch("app.st")
    def test_always_shows_retrieval_details(self, mock_st):
        """Should always show retrieval details JSON."""
        from app import render_debug_info
        
        debug_info = {
            "query": "Test",
            "query_rewritten": False,
            "stage1_count": 10
        }
        
        render_debug_info(debug_info)
        
        mock_st.json.assert_called_once()