const { RelocationRequest, Outlet, User, Worknote } = require('../models');
const { Op } = require('sequelize');
const { v4: uuidv4 } = require('uuid');

exports.submitRequest = async (req, res) => {
  try {
    const {
      outletId, relocationType, currentAddress, currentCity, currentState,
      currentLatitude, currentLongitude, proposedAddress, proposedCity,
      proposedState, proposedLatitude, proposedLongitude, reason, proposedDate
    } = req.body;

    const requestId = `REL-${Date.now()}-${uuidv4().substring(0, 4).toUpperCase()}`;

    const request = await RelocationRequest.create({
      requestId,
      outletId,
      dealerId: req.user.id,
      relocationType,
      currentAddress,
      currentCity,
      currentState,
      currentLatitude,
      currentLongitude,
      proposedAddress,
      proposedCity,
      proposedState,
      proposedLatitude,
      proposedLongitude,
      reason,
      proposedDate,
      currentStage: 'RBM Review',
      status: 'Pending',
      progressPercentage: 0,
      timeline: [{
        stage: 'Submitted',
        timestamp: new Date(),
        user: req.user.full_name, // Assuming req.user.full_name is available
        action: 'Request submitted'
      }]
    });

    res.status(201).json({
      success: true,
      message: 'Relocation request submitted successfully',
      requestId: request.requestId
    });
  } catch (error) {
    console.error('Submit relocation error:', error);
    res.status(500).json({ success: false, message: 'Error submitting request' });
  }
};

exports.getRequests = async (req, res) => {
  try {
    const where = {};
    if (req.user.role === 'Dealer') {
      where.dealerId = req.user.id;
    }

    const requests = await RelocationRequest.findAll({
      where,
      include: [
        {
          model: Outlet,
          as: 'outlet',
          attributes: ['code', 'name']
        },
        {
          model: User,
          as: 'dealer',
          attributes: ['full_name'] // Changed 'name' to 'full_name' based on original query
        }
      ],
      order: [['createdAt', 'DESC']]
    });

    res.json({ success: true, requests });
  } catch (error) {
    console.error('Get relocation requests error:', error);
    res.status(500).json({ success: false, message: 'Error fetching requests' });
  }
};

exports.getRequestById = async (req, res) => {
  try {
    const { id } = req.params;

    const request = await RelocationRequest.findOne({
      where: {
        [Op.or]: [
          { id },
          { requestId: id }
        ]
      },
      include: [
        {
          model: Outlet,
          as: 'outlet'
        },
        {
          model: User,
          as: 'dealer',
          attributes: ['full_name', 'email'] // Changed 'name' to 'full_name'
        },
        {
          model: Worknote,
          as: 'worknotes', // Assuming Worknote model is for workflow/comments
          include: [{
            model: User,
            as: 'actionedBy', // Assuming Worknote has an association to User for actioned_by
            attributes: ['full_name']
          }],
          order: [['createdAt', 'ASC']]
        }
      ]
    });

    if (!request) {
      return res.status(404).json({ success: false, message: 'Request not found' });
    }

    // Calculate distance between current and proposed location (retained from original)
    if (request.currentLatitude && request.proposedLatitude) {
      const distance = calculateDistance(
        request.currentLatitude, request.currentLongitude,
        request.proposedLatitude, request.proposedLongitude
      );
      request.dataValues.distance = `${distance.toFixed(2)} km`; // Add to dataValues for response
    }

    res.json({ success: true, request });
  } catch (error) {
    console.error('Get relocation details error:', error);
    res.status(500).json({ success: false, message: 'Error fetching details' });
  }
};

exports.takeAction = async (req, res) => {
  try {
    const { id } = req.params;
    const { action, comments } = req.body;

    const request = await RelocationRequest.findOne({
      where: {
        [Op.or]: [
          { id },
          { requestId: id }
        ]
      }
    });

    if (!request) {
      return res.status(404).json({ success: false, message: 'Request not found' });
    }

    // Update status and current_stage based on action
    let newStatus = request.status;
    let newCurrentStage = request.currentStage;

    if (action === 'Approved') {
      newStatus = 'Approved';
      // Assuming next stage logic would be here, e.g., 'Final Approval'
    } else if (action === 'Rejected') {
      newStatus = 'Rejected';
    } else if (action === 'Forwarded to RBM') {
      newCurrentStage = 'RBM Review';
    } else if (action === 'Forwarded to ZBM') {
      newCurrentStage = 'ZBM Review';
    } else if (action === 'Forwarded to HO') {
      newCurrentStage = 'HO Review';
    }

    // Create a worknote entry
    await Worknote.create({
      requestId: request.id,
      stage: newCurrentStage, // Or the specific stage where action was taken
      action: action,
      comments: comments,
      actionedBy: req.user.id,
      actionedAt: new Date()
    });

    // Update the request status and current stage
    await request.update({
      status: newStatus,
      currentStage: newCurrentStage,
      updatedAt: new Date()
    });

    res.json({ success: true, message: `Request ${action.toLowerCase()} successfully` });
  } catch (error) {
    console.error('Take action error:', error);
    res.status(500).json({ success: false, message: 'Error processing action' });
  }
};

exports.uploadDocuments = async (req, res) => {
  try {
    const { id } = req.params;
    const { documents } = req.body;

    const request = await RelocationRequest.findOne({
      where: {
        [Op.or]: [
          { id },
          { requestId: id }
        ]
      }
    });

    if (!request) {
      return res.status(404).json({ success: false, message: 'Request not found' });
    }

    await request.update({
      documents: documents,
      updatedAt: new Date()
    });

    res.json({ success: true, message: 'Documents uploaded successfully' });
  } catch (error) {
    console.error('Upload documents error:', error);
    res.status(500).json({ success: false, message: 'Error uploading documents' });
  }
};

// Helper function to calculate distance between two coordinates
function calculateDistance(lat1, lon1, lat2, lon2) {
  const R = 6371; // Radius of Earth in km
  const dLat = (lat2 - lat1) * Math.PI / 180;
  const dLon = (lon2 - lon1) * Math.PI / 180;
  const a = Math.sin(dLat / 2) * Math.sin(dLat / 2) +
    Math.cos(lat1 * Math.PI / 180) * Math.cos(lat2 * Math.PI / 180) *
    Math.sin(dLon / 2) * Math.sin(dLon / 2);
  const c = 2 * Math.atan2(Math.sqrt(a), Math.sqrt(1 - a));
  return R * c;
}