const express = require('express');
const router = express.Router();
const { getTenantDb, requireAuth } = require('./auth');
const eventBus = require('./eventBus');

// 1. GET /api/leads - Fetch all leads scoped by tenant organization via RLS
router.get('/', requireAuth, async (req, res) => {
  try {
    const db = getTenantDb(req);
    
    // RLS in Supabase PostgreSQL automatically handles tenant scoping & role boundaries
    const { data: leads, error } = await db
      .from('leads')
      .select(`
        *,
        counselors (
          name
        ),
        admissions (
          course,
          fees,
          payment_status
        )
      `)
      .order('created_at', { ascending: false });

    if (error) throw error;

    const formattedLeads = (leads || []).map(lead => {
      const hasAdmission = lead.admissions && lead.admissions.length > 0;
      const admissionRecord = hasAdmission ? lead.admissions[0] : null;
      
      let followupTime = 'One Day';
      if (lead.notes) {
        try {
          const parsed = JSON.parse(lead.notes);
          if (parsed.followup_time) {
            followupTime = parsed.followup_time;
          }
        } catch (e) {}
      }

      return {
        id: lead.id,
        student_name: lead.name,
        phone_number: lead.phone,
        email: lead.email || '',
        interested_course: lead.course_interested,
        lead_source: lead.source,
        counselor_name: lead.counselors ? lead.counselors.name : '',
        followup_status: lead.status || 'Pending',
        followup_time: followupTime,
        admission_status: hasAdmission ? 'Admitted' : 'Not Admitted',
        fees: admissionRecord ? parseFloat(admissionRecord.fees || 0) : 0,
        lead_score: lead.lead_score || 50,
        created_date: lead.created_at
      };
    });

    res.json(formattedLeads);
  } catch (error) {
    console.error('Error fetching leads:', error);
    res.status(500).json({ error: 'Internal Server Error' });
  }
});

// 2. PUT /api/update-lead - Update a lead's follow-up or admission status
router.put('/update-lead', requireAuth, async (req, res) => {
  const { phone_number, followup_status, admission_status, followup_time } = req.body;
  
  if (!phone_number) {
    return res.status(400).json({ error: 'Phone number is required' });
  }

  try {
    const db = getTenantDb(req);
    
    // Find the lead first
    const { data: leads, error: findError } = await db
      .from('leads')
      .select('id, name, course_interested, status, counselor_id, notes, organization_id, branch_id')
      .eq('phone', phone_number);

    if (findError) throw findError;

    if (!leads || leads.length === 0) {
      return res.status(404).json({ error: 'Lead not found' });
    }

    const lead = leads[0];

    // Parse metadata notes JSON
    let metadata = {};
    try {
      if (lead.notes && lead.notes.startsWith('{')) {
        metadata = JSON.parse(lead.notes);
      } else if (lead.notes) {
        metadata = { text_notes: lead.notes };
      }
    } catch (e) {}

    let notesUpdated = false;
    if (followup_time) {
      metadata.followup_time = followup_time;
      notesUpdated = true;
    }

    // Prepare lead updates
    const leadUpdates = {};
    const oldStatus = lead.status;
    if (followup_status && followup_status !== lead.status) {
      leadUpdates.status = followup_status;
    }
    if (notesUpdated) {
      leadUpdates.notes = JSON.stringify(metadata);
    }

    if (Object.keys(leadUpdates).length > 0) {
      const { error: updateLeadError } = await db
        .from('leads')
        .update(leadUpdates)
        .eq('id', lead.id);

      if (updateLeadError) throw updateLeadError;

      // Log followup details if status changed
      if (followup_status && followup_status !== oldStatus) {
        await db.from('follow_ups').insert([{
          lead_id: lead.id,
          organization_id: lead.organization_id,
          branch_id: lead.branch_id,
          followup_date: new Date().toISOString(),
          followup_type: 'Call',
          status: followup_status === 'Pending' ? 'Pending' : 'Completed',
          remarks: `Status updated via CRM to ${followup_status}`,
          created_by: lead.counselor_id
        }]);

        // Publish event to decoupled Event Bus
        eventBus.publish('lead.status_changed', {
          lead_id: lead.id,
          student_name: lead.name,
          phone: phone_number,
          old_status: oldStatus,
          new_status: followup_status,
          followup_time: followup_time || 'One Day',
          organization_id: lead.organization_id,
          branch_id: lead.branch_id
        });
      }
    }

    // Update admissions status
    if (admission_status) {
      const { data: existingAdmissions, error: admSelectError } = await db
        .from('admissions')
        .select('id')
        .eq('lead_id', lead.id);

      if (admSelectError) throw admSelectError;

      const hasAdmissionRecord = existingAdmissions && existingAdmissions.length > 0;

      if (admission_status === 'Admitted' && !hasAdmissionRecord) {
        // Trigger Lead Converted Event Bus sequence
        eventBus.publish('lead.converted', {
          lead_id: lead.id,
          student_name: lead.name,
          phone: phone_number,
          course: lead.course_interested || 'Default Course',
          counselor_id: lead.counselor_id,
          organization_id: lead.organization_id,
          branch_id: lead.branch_id
        });
      } else if (admission_status === 'Not Admitted' && hasAdmissionRecord) {
        // Remove admission details
        const { error: deleteAdmError } = await db
          .from('admissions')
          .delete()
          .eq('lead_id', lead.id);
        if (deleteAdmError) throw deleteAdmError;
      }
    }

    res.json({ message: 'Lead updated successfully' });
  } catch (error) {
    console.error('Error updating lead:', error);
    res.status(500).json({ error: 'Internal Server Error' });
  }
});

module.exports = router;