<?php

namespace App\Services;

use App\Models\Work;
use App\Models\User;
use App\Models\Transaction;
use App\Models\Dealer;
use Carbon\Carbon;
use Illuminate\Support\Facades\DB;
use Illuminate\Support\Facades\Log;

class TechnicianReportService
{
    /**
     * Get technician report data for all works and mechanics on a specific date range
     */
    public function getTechnicianReportData($dealerId = null, $startDate = null, $endDate = null)
    {
        try {
            // Debug: Check all users and roles
            $allUsers = User::with('role')->get();
            Log::info('All users in database:', [
                'total_users' => $allUsers->count(),
                'users_with_roles' => $allUsers->map(function($user) {
                    $roleName = 'No role';
                    if ($user->role) {
                        $roleName = is_string($user->role) ? $user->role : $user->role->name;
                    }
                    return [
                        'id' => $user->id,
                        'name' => $user->name,
                        'role_id' => $user->role_id,
                        'role_name' => $roleName,
                        'dealer_id' => $user->dealer_id
                    ];
                })
            ]);

            // Get all works with category in single query
            $works = Work::with(['category'])
                ->orderBy('name')
                ->get();

            // Get all mechanics (users with role name = 'mechanic')
            $mechanics = User::with('role')->whereHas('role', function($query) {
                    $query->where('name', 'mechanic');
                })
                ->when($dealerId, function($query) use ($dealerId) {
                    return $query->where('dealer_id', $dealerId);
                })
                ->orderBy('name')
                ->get(['id', 'name', 'role_id', 'dealer_id']);

            // Fallback: If no mechanics found, get all users with dealer_id
            if ($mechanics->isEmpty()) {
                Log::info('No users with role "mechanic" found, using fallback: all users with dealer_id');
                $mechanics = User::with('role')->whereNotNull('dealer_id')
                    ->whereNotNull('role_id')
                    ->when($dealerId, function($query) use ($dealerId) {
                        return $query->where('dealer_id', $dealerId);
                    })
                    ->orderBy('name')
                    ->get(['id', 'name', 'role_id', 'dealer_id']);
            }

            Log::info('Mechanics found:', [
                'count' => $mechanics->count(),
                'dealer_id_filter' => $dealerId,
                'mechanics' => $mechanics->map(function($mechanic) {
                    $roleName = 'Unknown';
                    if ($mechanic->role) {
                        $roleName = is_string($mechanic->role) ? $mechanic->role : $mechanic->role->name;
                    }
                    return [
                        'id' => $mechanic->id,
                        'name' => $mechanic->name,
                        'role_id' => $mechanic->role_id,
                        'role_name' => $roleName,
                        'dealer_id' => $mechanic->dealer_id
                    ];
                })
            ]);

            // Get all transaction data in single optimized query
            $transactions = $this->getOptimizedTransactionData($dealerId, $startDate, $endDate, $mechanics->pluck('id'), $works->pluck('id'));

            Log::info('Transaction data:', [
                'transaction_count' => count($transactions),
                'sample_transactions' => array_slice($transactions, 0, 5, true)
            ]);

            $data = [];
            
            foreach ($works as $work) {
                $row = [
                    'work_id' => $work->id,
                    'work_name' => $work->name,
                    'work_code' => $work->shortname,
                    'category_name' => $work->category ? $work->category->name : '-',
                    'total_tickets' => 0
                ];

                // Calculate totals for each mechanic
                foreach ($mechanics as $mechanic) {
                    $key = $work->id . '_' . $mechanic->id;
                    $mechanicData = $transactions[$key] ?? ['total' => 0, 'completed' => 0, 'pending' => 0];
                    
                    $row["mechanic_{$mechanic->id}_total"] = $mechanicData['total'];
                    
                    // Add to totals
                    $row['total_tickets'] += $mechanicData['total'];
                }

                $data[] = $row;
            }

            Log::info('Final data prepared:', [
                'data_count' => count($data),
                'sample_data' => array_slice($data, 0, 2)
            ]);

            return [
                'data' => $data,
                'mechanics' => $mechanics,
                'works' => $works
            ];
            
        } catch (\Exception $e) {
            Log::error('Error in getTechnicianReportData: ' . $e->getMessage(), [
                'dealer_id' => $dealerId,
                'start_date' => $startDate,
                'end_date' => $endDate,
                'trace' => $e->getTraceAsString()
            ]);
            
            // Return empty data structure but with proper format
            return [
                'data' => [],
                'mechanics' => collect(),
                'works' => collect()
            ];
        }
    }

    /**
     * Get optimized transaction data in single query
     */
    private function getOptimizedTransactionData($dealerId = null, $startDate = null, $endDate = null, $mechanicIds = null, $workIds = null)
    {
        $query = Transaction::select(
            'work_id',
            'user_id',
            'status',
            DB::raw('COUNT(*) as count')
        )
        ->groupBy('work_id', 'user_id', 'status');

        if ($dealerId) {
            $query->where('dealer_id', $dealerId);
        }

        if ($startDate) {
            $query->where('date', '>=', $startDate);
        }

        if ($endDate) {
            $query->where('date', '<=', $endDate);
        }

        if ($mechanicIds && $mechanicIds->count() > 0) {
            $query->whereIn('user_id', $mechanicIds);
        }

        if ($workIds && $workIds->count() > 0) {
            $query->whereIn('work_id', $workIds);
        }

        // Remove index hint that doesn't exist
        $results = $query->get();

        // Organize data by work_id_user_id key
        $organizedData = [];
        
        foreach ($results as $result) {
            $key = $result->work_id . '_' . $result->user_id;
            
            if (!isset($organizedData[$key])) {
                $organizedData[$key] = [
                    'total' => 0,
                    'completed' => 0,
                    'pending' => 0
                ];
            }
            
            $organizedData[$key]['total'] += $result->count;
            
            if ($result->status == 1) {
                $organizedData[$key]['completed'] += $result->count;
            } else {
                $organizedData[$key]['pending'] += $result->count;
            }
        }

        return $organizedData;
    }

    /**
     * Get total ticket count for a specific work and mechanic (legacy method for backward compatibility)
     */
    private function getTicketCount($workId, $mechanicId, $dealerId = null, $startDate = null, $endDate = null)
    {
        $query = Transaction::where('work_id', $workId)
            ->where('user_id', $mechanicId);

        if ($dealerId) {
            $query->where('dealer_id', $dealerId);
        }

        if ($startDate) {
            $query->where('date', '>=', $startDate);
        }

        if ($endDate) {
            $query->where('date', '<=', $endDate);
        }

        return $query->count();
    }

    /**
     * Get completed ticket count for a specific work and mechanic (legacy method for backward compatibility)
     */
    private function getCompletedTicketCount($workId, $mechanicId, $dealerId = null, $startDate = null, $endDate = null)
    {
        $query = Transaction::where('work_id', $workId)
            ->where('user_id', $mechanicId)
            ->where('status', 1); // Assuming status 1 is completed

        if ($dealerId) {
            $query->where('dealer_id', $dealerId);
        }

        if ($startDate) {
            $query->where('date', '>=', $startDate);
        }

        if ($endDate) {
            $query->where('date', '<=', $endDate);
        }

        return $query->count();
    }

    /**
     * Get pending ticket count for a specific work and mechanic (legacy method for backward compatibility)
     */
    private function getPendingTicketCount($workId, $mechanicId, $dealerId = null, $startDate = null, $endDate = null)
    {
        $query = Transaction::where('work_id', $workId)
            ->where('user_id', $mechanicId)
            ->where('status', 0); // Assuming status 0 is pending

        if ($dealerId) {
            $query->where('dealer_id', $dealerId);
        }

        if ($startDate) {
            $query->where('date', '>=', $startDate);
        }

        if ($endDate) {
            $query->where('date', '<=', $endDate);
        }

        return $query->count();
    }

    /**
     * Get all dealers for filter
     */
    public function getDealers()
    {
        return Dealer::orderBy('name')->get(['id', 'name', 'dealer_code']);
    }

    /**
     * Get default dealer for filter (tidak perlu berbasis user)
     */
    public function getDefaultDealer()
    {
        // Dealer pertama saja jika ada
        return Dealer::orderBy('name')->first();
    }

    /**
     * Get mechanics for a specific dealer
     */
    public function getMechanicsByDealer($dealerId = null)
    {
        $query = User::with('role')->whereHas('role', function($query) {
                $query->where('name', 'mechanic');
            });
        
        if ($dealerId) {
            $query->where('dealer_id', $dealerId);
        }
        
        return $query->orderBy('name')->get(['id', 'name', 'dealer_id']);
    }

    /**
     * Get technician report data for Yajra DataTable
     */
    public function getTechnicianReportDataForDataTable($dealerId = null, $startDate = null, $endDate = null)
    {
        try {
            // Get all works with category
            $works = Work::with(['category'])
                ->orderBy('name')
                ->get();

            // Get all mechanics
            $mechanics = User::with('role')->whereHas('role', function($query) {
                    $query->where('name', 'mechanic');
                })
                ->when($dealerId, function($query) use ($dealerId) {
                    return $query->where('dealer_id', $dealerId);
                })
                ->orderBy('name')
                ->get(['id', 'name', 'role_id', 'dealer_id']);

            // Fallback: If no mechanics found, get all users with dealer_id
            if ($mechanics->isEmpty()) {
                Log::info('No users with role "mechanic" found, using fallback: all users with dealer_id');
                $mechanics = User::with('role')->whereNotNull('dealer_id')
                    ->whereNotNull('role_id')
                    ->when($dealerId, function($query) use ($dealerId) {
                        return $query->where('dealer_id', $dealerId);
                    })
                    ->orderBy('name')
                    ->get(['id', 'name', 'role_id', 'dealer_id']);
            }

            // Get transaction data
            $transactions = $this->getOptimizedTransactionData($dealerId, $startDate, $endDate, $mechanics->pluck('id'), $works->pluck('id'));

            $data = [];
            
            foreach ($works as $work) {
                $row = [
                    'DT_RowIndex' => count($data) + 1,
                    'work_name' => $work->name,
                    'work_code' => $work->shortname,
                    'category_name' => $work->category ? $work->category->name : '-'
                ];

                // Add mechanic columns
                foreach ($mechanics as $mechanic) {
                    $key = $work->id . '_' . $mechanic->id;
                    $mechanicData = $transactions[$key] ?? ['total' => 0, 'completed' => 0, 'pending' => 0];
                    
                    $row["mechanic_{$mechanic->id}_total"] = $mechanicData['total'];
                }

                $data[] = $row;
            }

            // Create DataTable response
            return response()->json([
                'draw' => request()->input('draw', 1),
                'recordsTotal' => count($data),
                'recordsFiltered' => count($data),
                'data' => $data,
                'mechanics' => $mechanics,
                'works' => $works
            ]);
            
        } catch (\Exception $e) {
            Log::error('Error in getTechnicianReportDataForDataTable: ' . $e->getMessage(), [
                'dealer_id' => $dealerId,
                'start_date' => $startDate,
                'end_date' => $endDate,
                'trace' => $e->getTraceAsString()
            ]);
            
            return response()->json([
                'draw' => request()->input('draw', 1),
                'recordsTotal' => 0,
                'recordsFiltered' => 0,
                'data' => [],
                'mechanics' => collect(),
                'works' => collect()
            ]);
        }
    }

}