import { Request, Response } from 'express';
import * as readingService from '../services/reading.service';

/**
 * GET /readings
 * List all readings with pagination and filtering
 */
export async function getAll(req: Request, res: Response): Promise<void> {
  try {
    const {
      page = '1',
      pageSize = '50',
      meter_id,
      concentrator_id,
      project_id,
      start_date,
      end_date,
      reading_type,
    } = req.query;

    const filters: readingService.ReadingFilters = {};
    if (meter_id) filters.meter_id = meter_id as string;
    if (concentrator_id) filters.concentrator_id = concentrator_id as string;
    if (project_id) filters.project_id = project_id as string;
    if (start_date) filters.start_date = start_date as string;
    if (end_date) filters.end_date = end_date as string;
    if (reading_type) filters.reading_type = reading_type as string;

    const pagination = {
      page: parseInt(page as string, 10),
      pageSize: Math.min(parseInt(pageSize as string, 10), 100), // Max 100 per page
    };

    const result = await readingService.getAll(filters, pagination);

    res.status(200).json({
      success: true,
      data: result.data,
      pagination: result.pagination,
    });
  } catch (error) {
    console.error('Error fetching readings:', error);
    res.status(500).json({
      success: false,
      error: 'Internal server error',
    });
  }
}

/**
 * GET /readings/:id
 * Get a single reading by ID
 */
export async function getById(req: Request, res: Response): Promise<void> {
  try {
    const { id } = req.params;

    const reading = await readingService.getById(id);

    if (!reading) {
      res.status(404).json({
        success: false,
        error: 'Reading not found',
      });
      return;
    }

    res.status(200).json({
      success: true,
      data: reading,
    });
  } catch (error) {
    console.error('Error fetching reading:', error);
    res.status(500).json({
      success: false,
      error: 'Internal server error',
    });
  }
}

/**
 * POST /readings
 * Create a new reading
 */
export async function create(req: Request, res: Response): Promise<void> {
  try {
    const data = req.body as readingService.CreateReadingInput;

    const reading = await readingService.create(data);

    res.status(201).json({
      success: true,
      data: reading,
    });
  } catch (error) {
    console.error('Error creating reading:', error);
    res.status(500).json({
      success: false,
      error: 'Internal server error',
    });
  }
}

/**
 * DELETE /readings/:id
 * Delete a reading
 */
export async function deleteReading(req: Request, res: Response): Promise<void> {
  try {
    const { id } = req.params;

    const deleted = await readingService.deleteReading(id);

    if (!deleted) {
      res.status(404).json({
        success: false,
        error: 'Reading not found',
      });
      return;
    }

    res.status(200).json({
      success: true,
      data: { message: 'Reading deleted successfully' },
    });
  } catch (error) {
    console.error('Error deleting reading:', error);
    res.status(500).json({
      success: false,
      error: 'Internal server error',
    });
  }
}

/**
 * GET /readings/summary
 * Get consumption summary statistics
 */
export async function getSummary(req: Request, res: Response): Promise<void> {
  try {
    const { project_id } = req.query;

    const summary = await readingService.getConsumptionSummary(
      project_id as string | undefined
    );

    res.status(200).json({
      success: true,
      data: summary,
    });
  } catch (error) {
    console.error('Error fetching summary:', error);
    res.status(500).json({
      success: false,
      error: 'Internal server error',
    });
  }
}