"""FDAM Pipeline Orchestrator.

Coordinates the 6-stage processing pipeline:
1. Input Validation
2. Vision Analysis
3. RAG Retrieval
4. FDAM Logic (Dispositions)
5. Calculations
6. Document Generation
"""

import logging
import time
from dataclasses import dataclass, field
from datetime import datetime
from typing import Callable, Optional, TYPE_CHECKING
from PIL import Image
import io

from ui.state import SessionState
from ui.components import image_store
from models.loader import get_models

logger = logging.getLogger(__name__)

# Type hints only - actual import deferred to retriever property
if TYPE_CHECKING:
    from rag import FDAMRetriever, ChromaVectorStore

from .calculations import FDAMCalculator
from .dispositions import DispositionEngine, SurfaceDisposition
from .generator import DocumentGenerator, GeneratedDocument


@dataclass
class PipelineProgress:
    """Progress information for pipeline execution."""

    stage: int
    total_stages: int
    stage_name: str
    percent: float
    message: str


@dataclass
class VisionResult:
    """Result from vision analysis of a single image."""

    image_id: str
    filename: str
    room_id: str
    zone: dict
    condition: dict
    materials: list[dict]
    bounding_boxes: list[dict]
    raw_response: dict


@dataclass
class PipelineResult:
    """Complete result from pipeline execution."""

    success: bool
    session: SessionState
    vision_results: dict[str, VisionResult]
    dispositions: list[SurfaceDisposition]
    calculations: dict
    document: Optional[GeneratedDocument]
    annotated_images: list[tuple]  # (PIL.Image, caption)
    errors: list[str] = field(default_factory=list)
    warnings: list[str] = field(default_factory=list)
    execution_time_seconds: float = 0.0


ProgressCallback = Callable[[PipelineProgress], None]


class FDAMPipeline:
    """Main FDAM processing pipeline."""

    STAGES = [
        "Validating inputs",
        "Analyzing images",
        "Retrieving context",
        "Applying FDAM logic",
        "Running calculations",
        "Generating documents",
    ]

    def __init__(
        self,
        calculator: Optional[FDAMCalculator] = None,
        disposition_engine: Optional[DispositionEngine] = None,
        generator: Optional[DocumentGenerator] = None,
        retriever: Optional["FDAMRetriever"] = None,
    ):
        """Initialize pipeline with optional component overrides.

        Args:
            calculator: FDAM calculator instance
            disposition_engine: Disposition engine instance
            generator: Document generator instance
            retriever: RAG retriever instance
        """
        self.calculator = calculator or FDAMCalculator()
        self._retriever = retriever
        self.disposition_engine = disposition_engine or DispositionEngine(
            retriever=self._retriever
        )
        self.generator = generator or DocumentGenerator(
            calculator=self.calculator,
            disposition_engine=self.disposition_engine,
            retriever=self._retriever,
        )

    @property
    def retriever(self) -> "FDAMRetriever":
        """Get or create RAG retriever."""
        if self._retriever is None:
            # Lazy import to avoid chromadb dependency at module load
            from rag import FDAMRetriever, ChromaVectorStore
            try:
                vs = ChromaVectorStore(persist_directory="chroma_db")
                self._retriever = FDAMRetriever(vectorstore=vs)
            except Exception as e:
                logger.warning(f"ChromaDB init failed, using fallback retriever: {e}")
                self._retriever = FDAMRetriever()
        return self._retriever

    def execute(
        self,
        session: SessionState,
        progress_callback: Optional[ProgressCallback] = None,
    ) -> PipelineResult:
        """Execute the full FDAM pipeline.

        Args:
            session: Session state with all input data
            progress_callback: Optional callback for progress updates

        Returns:
            PipelineResult with all outputs
        """
        pipeline_start = time.time()
        start_time = datetime.now()
        errors = []
        warnings = []

        logger.info("=" * 60)
        logger.info("FDAM PIPELINE EXECUTION STARTED")
        logger.info("=" * 60)
        logger.info(f"Room: {session.room.name}")
        logger.info(f"Facility: {session.room.facility_classification}")
        logger.info(f"Images: {len(session.images)}")

        def report_progress(stage: int, message: str = ""):
            if progress_callback:
                progress_callback(
                    PipelineProgress(
                        stage=stage,
                        total_stages=len(self.STAGES),
                        stage_name=self.STAGES[stage - 1] if stage > 0 else "Starting",
                        percent=stage / len(self.STAGES),
                        message=message,
                    )
                )

        # Stage 1: Input Validation
        stage_start = time.time()
        logger.info("Stage 1/6: Input Validation")
        report_progress(1, "Validating inputs...")
        can_generate, validation_errors = session.can_generate()

        # Check images in store
        expected_ids = [img.id for img in session.images]
        missing_ids = image_store.get_missing_ids(expected_ids)

        if not can_generate or missing_ids:
            errors.extend(validation_errors)
            if missing_ids:
                errors.append(f"{len(missing_ids)} image(s) need to be re-uploaded")

            logger.error(f"Validation failed with {len(errors)} error(s)")
            for err in errors:
                logger.error(f"  - {err}")

            return PipelineResult(
                success=False,
                session=session,
                vision_results={},
                dispositions=[],
                calculations={},
                document=None,
                annotated_images=[],
                errors=errors,
                execution_time_seconds=(datetime.now() - start_time).total_seconds(),
            )

        logger.debug(f"Stage 1 completed in {time.time() - stage_start:.2f}s")

        # Stage 2: Vision Analysis
        stage_start = time.time()
        logger.info(f"Stage 2/6: Vision Analysis ({len(session.images)} images)")
        report_progress(2, "Analyzing images with AI...")
        model_stack = get_models()
        vision_results = {}
        annotated_images = []
        room_mapping = {}

        for i, img_meta in enumerate(session.images):
            logger.debug(f"Analyzing image {i+1}/{len(session.images)}: {img_meta.filename}")
            img_bytes = image_store.get(img_meta.id)
            if not img_bytes:
                warnings.append(f"Image {img_meta.filename} not found in store")
                continue

            try:
                pil_image = Image.open(io.BytesIO(img_bytes))

                # Run vision analysis
                result = model_stack.vision.analyze_image(
                    pil_image,
                    img_meta.description or "",
                )

                vision_result = VisionResult(
                    image_id=img_meta.id,
                    filename=img_meta.filename,
                    room_id=img_meta.room_id,
                    zone=result.get("zone", {}),
                    condition=result.get("condition", {}),
                    materials=result.get("materials", []),
                    bounding_boxes=result.get("bounding_boxes", []),
                    raw_response=result,
                )
                vision_results[img_meta.id] = vision_result

                # Build room mapping (single room)
                room_mapping[img_meta.id] = {
                    "name": session.room.name,
                    "id": session.room.id,
                }

                # Create annotated image caption
                zone_class = result.get("zone", {}).get("classification", "N/A")
                zone_conf = result.get("zone", {}).get("confidence", 0)
                caption = f"{img_meta.filename}\nZone: {zone_class} ({zone_conf:.0%})"
                annotated_images.append((pil_image, caption))

                report_progress(
                    2,
                    f"Analyzed {i + 1}/{len(session.images)}: {img_meta.filename}",
                )

            except Exception as e:
                logger.warning(f"Error analyzing {img_meta.filename}: {e}")
                warnings.append(f"Error analyzing {img_meta.filename}: {e}")

        logger.info(f"Stage 2 completed in {time.time() - stage_start:.2f}s: "
                   f"{len(vision_results)} images analyzed")

        # Stage 3: RAG Retrieval
        stage_start = time.time()
        logger.info("Stage 3/6: RAG Retrieval")
        report_progress(3, "Retrieving FDAM methodology context...")

        # RAG is integrated into disposition engine, just verify connection
        try:
            test_results = self.retriever.retrieve("test connection", top_k=1)
            logger.debug(f"RAG connection verified: {len(test_results)} results")
        except Exception as e:
            logger.warning(f"RAG retrieval unavailable: {e}")
            warnings.append(f"RAG retrieval unavailable: {e}")

        logger.debug(f"Stage 3 completed in {time.time() - stage_start:.2f}s")

        # Stage 4: FDAM Logic (Dispositions)
        stage_start = time.time()
        logger.info("Stage 4/6: FDAM Logic (Dispositions)")
        report_progress(4, "Applying disposition logic...")

        # Convert vision results to dict format for disposition engine
        vision_dict = {
            img_id: {
                "zone": vr.zone,
                "condition": vr.condition,
                "materials": vr.materials,
            }
            for img_id, vr in vision_results.items()
        }

        dispositions = self.disposition_engine.process_vision_results(
            vision_results=vision_dict,
            room_mapping=room_mapping,
        )
        logger.info(f"Stage 4 completed in {time.time() - stage_start:.2f}s: "
                   f"{len(dispositions)} dispositions generated")

        # Stage 5: Calculations
        stage_start = time.time()
        logger.info("Stage 5/6: Calculations")
        report_progress(5, "Running FDAM calculations...")
        calculations = self.calculator.calculate_from_session(session)
        logger.debug(f"Calculations: area={calculations.get('total_area_sf', 0):.0f} SF, "
                    f"volume={calculations.get('total_volume_cf', 0):.0f} CF")
        logger.debug(f"Stage 5 completed in {time.time() - stage_start:.2f}s")

        # Stage 6: Document Generation
        stage_start = time.time()
        logger.info("Stage 6/6: Document Generation")
        report_progress(6, "Generating documents...")
        document = self.generator.generate_sow(
            session=session,
            vision_results=vision_dict,
            surface_dispositions=dispositions,
            calculations=calculations,
        )
        logger.info(f"Stage 6 completed in {time.time() - stage_start:.2f}s: "
                   f"{len(document.sections)} sections generated")

        # Update session
        session.has_results = True
        session.results_generated_at = datetime.now().isoformat()
        session.update_timestamp()

        execution_time = (datetime.now() - start_time).total_seconds()
        total_time = time.time() - pipeline_start

        # Log final summary
        logger.info("=" * 60)
        logger.info("PIPELINE EXECUTION SUMMARY")
        logger.info("=" * 60)
        logger.info("Success: True")
        logger.info(f"Total execution time: {total_time:.2f}s")
        logger.info(f"Images analyzed: {len(vision_results)}")
        logger.info(f"Dispositions generated: {len(dispositions)}")
        logger.info(f"Document sections: {len(document.sections)}")
        logger.info(f"Warnings: {len(warnings)}")
        if warnings:
            for w in warnings:
                logger.warning(f"  - {w}")
        logger.info("=" * 60)

        return PipelineResult(
            success=True,
            session=session,
            vision_results=vision_results,
            dispositions=dispositions,
            calculations=calculations,
            document=document,
            annotated_images=annotated_images,
            errors=errors,
            warnings=warnings,
            execution_time_seconds=execution_time,
        )

    def generate_stats_dict(self, result: PipelineResult) -> dict:
        """Generate statistics dictionary for UI display.

        Args:
            result: Pipeline execution result

        Returns:
            Dictionary with stats for JSON display
        """
        calc = result.calculations
        air = calc.get("air_filtration")
        sample = calc.get("sample_density")
        reg = calc.get("regulatory_flags")
        thresholds = calc.get("metals_thresholds")

        # Count dispositions by type
        disp_counts = {}
        for d in result.dispositions:
            disp_counts[d.disposition] = disp_counts.get(d.disposition, 0) + 1

        return {
            "room_name": result.session.room.name,
            "facility_classification": result.session.room.facility_classification,
            "construction_era": result.session.room.construction_era,
            "total_images": len(result.session.images),
            "images_analyzed": len(result.vision_results),
            "total_floor_area_sf": f"{calc.get('total_area_sf', 0):,.0f}",
            "total_volume_cf": f"{calc.get('total_volume_cf', 0):,.0f}",
            "air_scrubbers_required": air.units_required if air else 0,
            "tape_lifts_recommended": f"{sample.tape_lifts_min}-{sample.tape_lifts_max}" if sample else "N/A",
            "surface_wipes_recommended": f"{sample.surface_wipes_min}-{sample.surface_wipes_max}" if sample else "N/A",
            "disposition_counts": disp_counts,
            "regulatory_flags": reg.notes if reg else [],
            "lead_threshold": f"{thresholds.lead_ug_100cm2} µg/100cm²" if thresholds else "N/A",
            "execution_time": f"{result.execution_time_seconds:.1f}s",
            "warnings": result.warnings,
        }