from decimal import Decimal

from fastapi import FastAPI, Request
from fastapi.staticfiles import StaticFiles
from fastapi.templating import Jinja2Templates
from sqlalchemy import create_engine, func
from sqlalchemy.orm import sessionmaker

from app.core.config import DATABASE_URL
from app.models.document import Document
from app.models.extracted_field import ExtractedField
from app.models.receipt_line_item import ReceiptLineItem
from app.routes.documents import router as documents_router
from app.routes.health import router as health_router
from app.routes.ingest import router as ingest_router
from app.routes.line_items import router as line_items_router
from app.routes.queue import router as queue_router
from app.routes.presets import router as presets_router
from app.routes.trash import router as trash_router

app = FastAPI(title="document-processor")
app.mount("/static", StaticFiles(directory="app/static"), name="static")
app.mount("/files", StaticFiles(directory="/mnt/storage/document-processor"), name="files")

app.include_router(health_router)
app.include_router(documents_router)
app.include_router(ingest_router)
app.include_router(line_items_router)
app.include_router(queue_router)
app.include_router(presets_router)
app.include_router(trash_router)

templates = Jinja2Templates(directory="app/templates")

engine = create_engine(DATABASE_URL)
SessionLocal = sessionmaker(bind=engine)


def _to_str(value) -> str:
    if value is None:
        return ""
    return str(value)


@app.get("/")
def root_dashboard(request: Request):
    db = SessionLocal()
    try:
        total_documents = db.query(func.count(Document.id)).scalar() or 0
        active_documents = (
            db.query(func.count(Document.id))
            .filter(Document.is_trashed.is_(False))
            .scalar()
            or 0
        )
        reviewed_documents = (
            db.query(func.count(Document.id))
            .filter(Document.is_trashed.is_(False))
            .filter(Document.review_status == "reviewed")
            .scalar()
            or 0
        )
        pending_review_documents = (
            db.query(func.count(Document.id))
            .filter(Document.is_trashed.is_(False))
            .filter(Document.review_status != "reviewed")
            .scalar()
            or 0
        )
        trashed_documents = (
            db.query(func.count(Document.id))
            .filter(Document.is_trashed.is_(True))
            .scalar()
            or 0
        )
        extracted_documents = db.query(func.count(ExtractedField.id)).scalar() or 0
        total_line_items = db.query(func.count(ReceiptLineItem.id)).scalar() or 0
        cocktail_count = (
            db.query(func.count(ReceiptLineItem.id))
            .filter(func.lower(ReceiptLineItem.item_category) == "cocktail")
            .scalar()
            or 0
        )

        quality_candidates = (
            db.query(ReceiptLineItem.extra_json)
            .filter(func.lower(ReceiptLineItem.item_category) == "cocktail")
            .all()
        )

        rated_cocktails = 0
        pending_cocktail_reviews = 0
        na_cocktails = 0
        rating_sum = Decimal("0")

        for (extra_json,) in quality_candidates:
            extra = extra_json or {}
            status = str(extra.get("quality_status") or "").strip().lower()
            rating_raw = str(extra.get("quality_rating") or "").strip()

            rating_dec = None
            if rating_raw:
                try:
                    rating_dec = Decimal(rating_raw)
                except Exception:
                    rating_dec = None

            if status == "na":
                na_cocktails += 1
            elif rating_dec is not None:
                rated_cocktails += 1
                rating_sum += rating_dec
            else:
                pending_cocktail_reviews += 1

        avg_cocktail_rating = ""
        if rated_cocktails > 0:
            avg_cocktail_rating = str((rating_sum / Decimal(rated_cocktails)).quantize(Decimal("0.01")))

        recent_documents = (
            db.query(Document)
            .filter(Document.is_trashed.is_(False))
            .order_by(Document.updated_at.desc())
            .limit(10)
            .all()
        )

        recent_line_items = (
            db.query(ReceiptLineItem)
            .join(Document, ReceiptLineItem.document_id == Document.id)
            .filter(Document.is_trashed.is_(False))
            .order_by(ReceiptLineItem.updated_at.desc())
            .limit(10)
            .all()
        )

        recent_line_item_rows = []
        for item in recent_line_items:
            doc = item.document
            merchant = ""
            transaction_date = ""
            if doc and doc.extracted_fields:
                extracted = sorted(
                    doc.extracted_fields,
                    key=lambda x: x.updated_at or x.created_at,
                    reverse=True,
                )[0]
                merchant = extracted.merchant_normalized or extracted.merchant_raw or ""
                if extracted.transaction_date:
                    transaction_date = extracted.transaction_date.isoformat()

            extra = item.extra_json or {}
            recent_line_item_rows.append(
                {
                    "document_id": doc.document_id if doc else "",
                    "merchant": merchant,
                    "transaction_date": transaction_date,
                    "description": item.normalized_description or item.raw_description or "",
                    "category": item.item_category or "",
                    "line_total": _to_str(item.line_total),
                    "quality_rating": _to_str(extra.get("quality_rating")),
                    "quality_status": _to_str(extra.get("quality_status")),
                }
            )

        return templates.TemplateResponse(
            request=request,
            name="dashboard.html",
            context={
                "request": request,
                "active_page": "",
                "total_documents": total_documents,
                "active_documents": active_documents,
                "reviewed_documents": reviewed_documents,
                "pending_review_documents": pending_review_documents,
                "trashed_documents": trashed_documents,
                "extracted_documents": extracted_documents,
                "total_line_items": total_line_items,
                "cocktail_count": cocktail_count,
                "rated_cocktails": rated_cocktails,
                "pending_cocktail_reviews": pending_cocktail_reviews,
                "na_cocktails": na_cocktails,
                "avg_cocktail_rating": avg_cocktail_rating,
                "recent_documents": recent_documents,
                "recent_line_items": recent_line_item_rows,
            },
        )
    finally:
        db.close()