"""
Analytics Service — Report Engine.

موتور تولید گزارش cross-module.
"""

import logging
from typing import Any, Dict, Optional

from django.utils import timezone

from .models import GeneratedReport, ReportTemplate

logger = logging.getLogger(__name__)


class ReportEngine:
    """موتور تولید گزارش — استخراج داده و تبدیل به فرمت خروجی."""

    def generate(self, report: GeneratedReport) -> Dict[str, Any]:
        """تولید گزارش از قالب و پارامترهای ورودی."""
        template = report.template
        parameters = report.parameters or {}
        output_format = report.format

        # Step 1: Extract data from modules
        data = self._extract_data(template, parameters)

        # Step 2: Format output
        result = self._format_output(data, template, output_format)

        return result

    def _extract_data(
        self,
        template: ReportTemplate,
        parameters: Dict,
    ) -> Dict[str, Any]:
        """استخراج داده از ماژول‌های مشخص‌شده."""
        query_def = template.query_definition or {}
        modules = template.modules or []

        data = {}
        for module_name in modules:
            try:
                module_data = self._query_module(module_name, query_def, parameters)
                data[module_name] = module_data
            except Exception as e:
                logger.error("Data extraction failed for module %s: %s", module_name, e)
                data[module_name] = {"error": str(e)}

        return data

    @staticmethod
    def _query_module(
        module_name: str,
        query_def: Dict,
        parameters: Dict,
    ) -> Dict[str, Any]:
        """کوئری یک ماژول خاص."""
        # TODO: Implement dynamic query execution per module
        # This should use the module's read-only API or direct DB access
        return {"module": module_name, "status": "not_implemented"}

    def _format_output(
        self,
        data: Dict[str, Any],
        template: ReportTemplate,
        output_format: str,
    ) -> Dict[str, Any]:
        """تبدیل داده به فرمت خروجی."""
        format_options = template.format_options or {}

        if output_format == "pdf":
            return self._generate_pdf(data, format_options)
        elif output_format == "excel":
            return self._generate_excel(data, format_options)
        elif output_format == "csv":
            return self._generate_csv(data, format_options)
        elif output_format == "html":
            return self._generate_html(data, format_options)
        else:
            return {"file_url": "", "file_size": 0}

    @staticmethod
    def _generate_pdf(data: Dict, options: Dict) -> Dict[str, Any]:
        """تولید فایل PDF."""
        # TODO: Implement PDF generation (jsPDF/WeasyPrint)
        logger.info("PDF report generation — placeholder")
        return {"file_url": "", "file_size": 0, "format": "pdf"}

    @staticmethod
    def _generate_excel(data: Dict, options: Dict) -> Dict[str, Any]:
        """تولید فایل Excel."""
        # TODO: Implement Excel generation (openpyxl)
        logger.info("Excel report generation — placeholder")
        return {"file_url": "", "file_size": 0, "format": "excel"}

    @staticmethod
    def _generate_csv(data: Dict, options: Dict) -> Dict[str, Any]:
        """تولید فایل CSV."""
        # TODO: Implement CSV generation
        logger.info("CSV report generation — placeholder")
        return {"file_url": "", "file_size": 0, "format": "csv"}

    @staticmethod
    def _generate_html(data: Dict, options: Dict) -> Dict[str, Any]:
        """تولید فایل HTML."""
        # TODO: Implement HTML generation
        logger.info("HTML report generation — placeholder")
        return {"file_url": "", "file_size": 0, "format": "html"}