"""Main leaudit pipeline orchestrator: OCR → Extract → Evaluate.

Uses leaudit's own pipeline directly (no conversion),
stores results into docauditai's database via StorageAdapter.
"""

from __future__ import annotations

import logging
import time
from dataclasses import dataclass, field
from pathlib import Path
from typing import Any


from leaudit.dsl.schema import RulesFile
from leaudit.engine.case_file_evaluator import evaluate_extraction
from leaudit.engine.models import EvaluationResult
from leaudit.extraction.bundle import ExtractionBundle
from leaudit.extraction.dispatcher import dispatch_extract
from leaudit.extraction.phase_detection import determine_phase
from leaudit.llm.base import BaseLLMClient
from leaudit.ocr.base import BaseOCRClient
from leaudit.ocr.models import OcrResult

from fastapi_modules.fastapi_leaudit.leaudit_bridge.storage_adapter import StorageAdapter

log = logging.getLogger(__name__)


def _ensure_text_page_chunks(ocr_result: OcrResult) -> None:
    """Backfill pseudo chunks for text-native pages that have no OCR chunks.

    DOCX/legacy-doc normalization currently produces page text but often no
    geometric chunks, which causes ``resolve_bundle_positions`` to return zero
    positions for every extracted field. We synthesize coarse text chunks so at
    least page-level定位 can be recovered on the review page.
    """
    for page in ocr_result.pages:
        if page.chunks:
            continue

        raw_text = page.text or ""
        normalized_text = (
            raw_text
            .replace("\r\n", "\n")
            .replace("\r", "\n")
        )
        blocks = [
            block.strip()
            for block in normalized_text.split("\n\n")
            if block.strip() and not block.strip().startswith("<!-- PAGE ")
        ]
        if not blocks:
            continue

        page.chunks = [
            {
                "content": block,
                "bbox": [0, 0, 0, 0],
                "label": "text",
            }
            for block in blocks
        ]
        page.bboxes = [chunk["bbox"] for chunk in page.chunks]


@dataclass
class PipelineResult:
    """Complete result from the leaudit pipeline."""

    ocr_result: OcrResult
    extraction_bundle: ExtractionBundle
    evaluation_result: EvaluationResult
    detected_phase: str
    timing: dict[str, float] = field(default_factory=dict)
    errors: list[str] = field(default_factory=list)


class LauditPipeline:
    """Run leaudit's full OCR → extraction → evaluation pipeline.

    Does NOT use leaudit's own SQLAlchemy storage.
    All results are written to docauditai's database via StorageAdapter.
    """

    def __init__(
        self,
        ocr_client: BaseOCRClient,
        llm_client: BaseLLMClient | None = None,
        storage_adapter: StorageAdapter | None = None,
    ) -> None:
        self.ocr_client = ocr_client
        self.llm_client = llm_client
        self.storage = storage_adapter or StorageAdapter()

    async def run(
        self,
        document_id: int,
        file_path: str | Path,
        rules_file: RulesFile | None = None,
        *,
        source_port: int = 8000,
    ) -> PipelineResult:
        """Execute the full pipeline for one document.

        Args:
            document_id: docauditai document ID for DB writes.
            file_path: Path to the document file (PDF/DOCX/etc).
            rules_file: leaudit RulesFile (parsed from YAML). When None,
                the pipeline attempts to load rules from the OCR result's
                ``rules_file_path`` (set by the classifier).
            source_port: Instance port for context switching.

        Returns:
            PipelineResult with all intermediate and final outputs.
        """
        file_path = Path(file_path)
        errors: list[str] = []
        timing: dict[str, float] = {}

        # --- Phase 1: Update status to Cutting ---
        await self.storage.update_document_status(document_id, "Cutting")

        # --- Phase 2: OCR ---
        t0 = time.time()
        log.info("[%d] OCR starting: %s", document_id, file_path.name)
        ocr_result = await self._run_ocr(file_path)
        _ensure_text_page_chunks(ocr_result)
        timing["ocr"] = round(time.time() - t0, 2)
        log.info(
            "[%d] OCR done: %d pages, %.1fs",
            document_id,
            len(ocr_result.pages),
            timing["ocr"],
        )

        # --- Resolve rules_file after OCR if not provided ---
        if rules_file is None:
            rules_file = await self._resolve_rules_from_ocr(ocr_result, document_id)
        if rules_file is None:
            raise ValueError(
                f"Cannot resolve rules_file for document {document_id}. "
                "Neither passed explicitly nor classified from OCR content."
            )

        # --- Save OCR result ---
        await self.storage.save_ocr_result(document_id, ocr_result)

        # --- Extract & save case number (案件编号) ---
        await self._extract_and_save_case_number(document_id, ocr_result)

        # --- Phase 3: Extraction ---
        t0 = time.time()
        await self.storage.update_document_status(document_id, "Extractioning")
        log.info("[%d] Extraction starting", document_id)

        extraction_bundle = await dispatch_extract(
            ocr_result,
            rules_file,
            llm_client=self.llm_client,
            phase="executed",
        )
        timing["extraction"] = round(time.time() - t0, 2)

        if extraction_bundle.all_errors:
            errors.extend(extraction_bundle.all_errors)
            log.warning(
                "[%d] Extraction completed with %d errors",
                document_id,
                len(extraction_bundle.all_errors),
            )

        log.info(
            "[%d] Extraction done: %d fields, %.1fs",
            document_id,
            len(extraction_bundle.fields),
            timing["extraction"],
        )

        # --- Resolve field positions from OCR chunks ---
        from leaudit.extraction.coordinate_resolver import resolve_bundle_positions
        resolve_bundle_positions(extraction_bundle, ocr_result)
        positioned_count = sum(
            1 for fv in extraction_bundle.fields.values() if fv.position is not None
        )
        log.info(
            "[%d] Coordinate resolution: %d/%d fields positioned",
            document_id,
            positioned_count,
            len(extraction_bundle.fields),
        )

        # --- Save extraction result ---
        await self.storage.save_extraction_result(document_id, extraction_bundle)

        # --- Phase 4: Phase detection ---
        visual_manifest = extraction_bundle.visual_manifest or ocr_result.visual_manifest
        detected_phase = await determine_phase(
            extraction_bundle.fields,
            llm_client=self.llm_client,
            visual_manifest=visual_manifest,
        )
        log.info("[%d] Detected phase: %s", document_id, detected_phase)

        # --- Phase 5: Evaluation ---
        t0 = time.time()
        await self.storage.update_document_status(document_id, "Evaluationing")
        log.info("[%d] Evaluation starting (phase=%s)", document_id, detected_phase)

        external_mocks: dict[str, Any] = {}
        if self.llm_client is not None:
            external_mocks["llm_client"] = self.llm_client
        external_mocks["rules_file"] = rules_file

        evaluation_result = await evaluate_extraction(
            rules_file,
            extraction_bundle,
            visual_manifest=visual_manifest,
            phase=detected_phase,
            external_mocks=external_mocks,
        )
        timing["evaluation"] = round(time.time() - t0, 2)
        log.info(
            "[%d] Evaluation done: %d passed, %d failed, %d skipped, %.1fs",
            document_id,
            evaluation_result.passed_count,
            evaluation_result.failed_count,
            evaluation_result.skipped_count,
            timing["evaluation"],
        )

        # --- Save evaluation results ---
        await self.storage.save_evaluation_results(
            document_id, rules_file, evaluation_result, extraction_bundle,
        )

        # --- Phase 6: Finalize ---
        timing["total"] = round(sum(timing.values()), 2)
        await self.storage.update_document_status(document_id, "Processed")

        log.info(
            "[%d] Pipeline complete: phase=%s, timing=%s",
            document_id,
            detected_phase,
            timing,
        )

        return PipelineResult(
            ocr_result=ocr_result,
            extraction_bundle=extraction_bundle,
            evaluation_result=evaluation_result,
            detected_phase=detected_phase,
            timing=timing,
            errors=errors,
        )

    async def _run_ocr(self, file_path: Path) -> OcrResult:
        """Run OCR with error handling."""
        try:
            return await self.ocr_client.ocr(file_path)
        except Exception as e:
            log.error("OCR failed for %s: %s", file_path.name, e)
            raise

    async def _extract_and_save_case_number(
        self, document_id: int, ocr_result: OcrResult,
    ) -> None:
        """Extract case number from OCR and write to database."""
        from fastapi_modules.fastapi_leaudit.leaudit_bridge.case_number_extractor import (
            extract_case_number_with_llm,
        )

        case_number = await extract_case_number_with_llm(
            ocr_result, llm_client=self.llm_client,
        )
        if case_number:
            await self.storage.update_document_number(document_id, case_number)
            log.info("[%d] Case number: %s", document_id, case_number)
        else:
            log.info("[%d] No case number found", document_id)

    async def _resolve_rules_from_ocr(
        self, ocr_result: OcrResult, document_id: int,
    ) -> RulesFile | None:
        """Load rules_file from OCR classification result."""
        from leaudit.dsl.loader import load_rules_file

        rfp = ocr_result.rules_file_path
        if not rfp:
            log.warning(
                "[%d] No rules_file_path in OCR result, cannot resolve rules",
                document_id,
            )
            return None

        try:
            rules_file = load_rules_file(rfp)
            log.info(
                "[%d] Resolved rules from classification: %s (%d rules)",
                document_id, rfp, len(rules_file.flat_rules),
            )
            return rules_file
        except Exception as e:
            log.error("[%d] Failed to load rules from %s: %s", document_id, rfp, e)
            return None