from fastapi import APIRouter, Query, Request, UploadFile, File
from fastapi.responses import StreamingResponse, HTMLResponse
from fastapi.templating import Jinja2Templates
from pydantic import BaseModel
from pathlib import Path
from typing import Optional
import io

from ..services import mapping_service, sqlite_service

import logging
logger = logging.getLogger(__name__)

router = APIRouter(tags=["mappings"])
templates = Jinja2Templates(directory=str(Path(__file__).parent.parent / "templates"))

class MappingCreate(BaseModel):
    sku: str
    codmat: str
    cantitate_roa: float = 1
    procent_pret: float = 100

class MappingUpdate(BaseModel):
    cantitate_roa: Optional[float] = None
    procent_pret: Optional[float] = None
    activ: Optional[int] = None

class MappingEdit(BaseModel):
    new_sku: str
    new_codmat: str
    cantitate_roa: float = 1
    procent_pret: float = 100

class MappingLine(BaseModel):
    codmat: str
    cantitate_roa: float = 1
    procent_pret: float = 100

class MappingBatchCreate(BaseModel):
    sku: str
    mappings: list[MappingLine]

# HTML page
@router.get("/mappings", response_class=HTMLResponse)
async def mappings_page(request: Request):
    return templates.TemplateResponse("mappings.html", {"request": request})

# API endpoints
@router.get("/api/mappings")
async def list_mappings(search: str = "", page: int = 1, per_page: int = 50,
                        sort_by: str = "sku", sort_dir: str = "asc",
                        show_deleted: bool = False):
    result = mapping_service.get_mappings(search=search, page=page, per_page=per_page,
                                           sort_by=sort_by, sort_dir=sort_dir,
                                           show_deleted=show_deleted)
    # Merge product names from web_products (R4)
    skus = list({m["sku"] for m in result.get("mappings", [])})
    product_names = await sqlite_service.get_web_products_batch(skus)
    for m in result.get("mappings", []):
        m["product_name"] = product_names.get(m["sku"], "")
    return result

@router.post("/api/mappings")
async def create_mapping(data: MappingCreate):
    try:
        result = mapping_service.create_mapping(data.sku, data.codmat, data.cantitate_roa, data.procent_pret)
        # Mark SKU as resolved in missing_skus tracking
        await sqlite_service.resolve_missing_sku(data.sku)
        return {"success": True, **result}
    except Exception as e:
        return {"success": False, "error": str(e)}

@router.put("/api/mappings/{sku}/{codmat}")
def update_mapping(sku: str, codmat: str, data: MappingUpdate):
    try:
        updated = mapping_service.update_mapping(sku, codmat, data.cantitate_roa, data.procent_pret, data.activ)
        return {"success": updated}
    except Exception as e:
        return {"success": False, "error": str(e)}

@router.put("/api/mappings/{sku}/{codmat}/edit")
def edit_mapping(sku: str, codmat: str, data: MappingEdit):
    try:
        result = mapping_service.edit_mapping(sku, codmat, data.new_sku, data.new_codmat,
                                               data.cantitate_roa, data.procent_pret)
        return {"success": result}
    except Exception as e:
        return {"success": False, "error": str(e)}

@router.delete("/api/mappings/{sku}/{codmat}")
def delete_mapping(sku: str, codmat: str):
    try:
        deleted = mapping_service.delete_mapping(sku, codmat)
        return {"success": deleted}
    except Exception as e:
        return {"success": False, "error": str(e)}

@router.post("/api/mappings/{sku}/{codmat}/restore")
def restore_mapping(sku: str, codmat: str):
    try:
        restored = mapping_service.restore_mapping(sku, codmat)
        return {"success": restored}
    except Exception as e:
        return {"success": False, "error": str(e)}

@router.post("/api/mappings/batch")
async def create_batch_mapping(data: MappingBatchCreate):
    """Create multiple (sku, codmat) rows for complex sets (R11)."""
    if not data.mappings:
        return {"success": False, "error": "No mappings provided"}

    # Validate procent_pret sums to 100 for multi-line sets
    if len(data.mappings) > 1:
        total_pct = sum(m.procent_pret for m in data.mappings)
        if abs(total_pct - 100) > 0.01:
            return {"success": False, "error": f"Procent pret trebuie sa fie 100% (actual: {total_pct}%)"}

    try:
        results = []
        for m in data.mappings:
            r = mapping_service.create_mapping(data.sku, m.codmat, m.cantitate_roa, m.procent_pret)
            results.append(r)
        # Mark SKU as resolved in missing_skus tracking
        await sqlite_service.resolve_missing_sku(data.sku)
        return {"success": True, "created": len(results)}
    except Exception as e:
        return {"success": False, "error": str(e)}


@router.post("/api/mappings/import-csv")
async def import_csv(file: UploadFile = File(...)):
    content = await file.read()
    text = content.decode("utf-8-sig")
    result = mapping_service.import_csv(text)
    return result

@router.get("/api/mappings/export-csv")
def export_csv():
    csv_content = mapping_service.export_csv()
    return StreamingResponse(
        io.BytesIO(csv_content.encode("utf-8-sig")),
        media_type="text/csv",
        headers={"Content-Disposition": "attachment; filename=mappings.csv"}
    )

@router.get("/api/mappings/csv-template")
def csv_template():
    content = mapping_service.get_csv_template()
    return StreamingResponse(
        io.BytesIO(content.encode("utf-8-sig")),
        media_type="text/csv",
        headers={"Content-Disposition": "attachment; filename=mappings_template.csv"}
    )