<?php

namespace App\Controllers;

use App\Models\ExpenseModel;
use App\Models\ClientModel;
use App\Models\ClientPolicyModel;
use CodeIgniter\API\ResponseTrait;

class ExpenseController extends AdminController
{
    use ResponseTrait;

    protected $myLogger;
    protected $expenseModel;
    protected $clientModel;
    protected $clientPolicyModel;

    public function __construct()
    {
        set_session_context('Expense');

        $this->myLogger         = \Config\Services::mylogger();
        $this->expenseModel     = new ExpenseModel();
        $this->clientModel      = new ClientModel();
        $this->clientPolicyModel = new ClientPolicyModel();
    }

    /**
     * Web list + form view
     */
    public function index()
    {
        try {
            $data['tab_name']  = 'Expense';
            $data['page_name'] = 'Expense';
            $descriptionPattern = '/^[a-zA-Z0-9\s\.\,\-\(\)\/\&\+\'"]+$/u';
            // Raw GET filters
            $rawFilters = $this->request->getGet() ?? [];
            $rawFilters = is_array($rawFilters) ? $rawFilters : [];

            // Sanitize input array using existing helper
            $sanitized = sanitizeInputArrayAdvanced($rawFilters);

            $filters = [
                'client_id'        => trim($sanitized['client_id'] ?? ''),
                'client_policy_id' => trim($sanitized['client_policy_id'] ?? ''),
                'approved_by'      => trim($sanitized['approved_by'] ?? ''),
                'description'      => trim($sanitized['description'] ?? ''),
                'amount'           => trim($sanitized['amount'] ?? ''),
                'expense_date'     => trim($sanitized['expense_date'] ?? ''),
            ];

            $validationErrors = [];

            // Basic type / format validation for filters
            if ($filters['client_id'] !== '' && ! ctype_digit($filters['client_id'])) {
                $validationErrors[]   = 'Invalid client selected for search.';
                $filters['client_id'] = '';
            }

            if ($filters['client_policy_id'] !== '' && ! ctype_digit($filters['client_policy_id'])) {
                $validationErrors[]         = 'Invalid policy selected for search.';
                $filters['client_policy_id'] = '';
            }

            if ($filters['approved_by'] !== '' && ! ctype_digit($filters['approved_by'])) {
                $validationErrors[]    = 'Invalid approver selected for search.';
                $filters['approved_by'] = '';
            }

            if ($filters['description'] !== '' && ! preg_match($descriptionPattern, $filters['description'])) {
                $validationErrors[]     = 'Description filter contains invalid characters.';
                $filters['description'] = '';
            }

            if ($filters['amount'] !== '') {
                if (! is_numeric($filters['amount']) || (float) $filters['amount'] < 0) {
                    $validationErrors[] = 'Amount filter must be a non-negative number.';
                    $filters['amount']  = '';
                }
            }

            if ($filters['expense_date'] !== '') {
                $dt = \DateTime::createFromFormat('d-m-Y', $filters['expense_date']);
                $errors = $dt ? \DateTime::getLastErrors() : ['warning_count' => 1, 'error_count' => 1];
                if (! $dt || ! empty($errors['warning_count']) || ! empty($errors['error_count'])) {
                    $validationErrors[]      = 'Expense Date filter must be in DD-MM-YYYY format.';
                    $filters['expense_date'] = '';
                }
            }

            $data['filters']           = $filters;
            $data['validation_errors'] = $validationErrors;

            // Clients for dropdown
            $data['clients'] = $this->clientModel
                ->select('id, client_name, short_name')
                ->where('client_type', 1)
                ->where('is_active', 1)
                ->orderBy('client_name', 'ASC')
                ->findAll();

            // Approved by (users) dropdown
            $db = db_connect();
            $data['approved_users'] = $db->table('user_profiles')
                ->select('id, first_name')
                ->where('is_active', 1)
                ->whereIn('id', [7, 8])
                ->orderBy('first_name', 'ASC')
                ->get()
                ->getResultArray();

            // Policies for filter dropdown (when client filter is selected)
            $data['policies_for_filter'] = [];
            if ($filters['client_id'] !== '') {
                $data['policies_for_filter'] = $this->clientPolicyModel
                    ->select('id, policy_no')
                    ->where('client_id', (int) $filters['client_id'])
                    ->where('is_active', 1)
                    ->orderBy('id', 'ASC')
                    ->findAll();
            }

            // Existing expenses with optional filters
            $builder = $this->expenseModel
                ->select('
                    expenses.*,
                    clients.client_name,
                    clients.short_name,
                    client_policy.policy_no,
                    user_profiles.first_name AS approved_by_name
                ')
                ->join('clients', 'clients.id = expenses.client_id')
                ->join('client_policy', 'client_policy.id = expenses.client_policy_id', 'left')
                ->join('user_profiles', 'user_profiles.id = expenses.approved_by', 'left')
                ->where('expenses.is_active', 1);

            if ($filters['client_id'] !== '') {
                $builder->where('expenses.client_id', (int) $filters['client_id']);
            }

            if ($filters['client_policy_id'] !== '') {
                $builder->where('expenses.client_policy_id', (int) $filters['client_policy_id']);
            }

            if ($filters['approved_by'] !== '') {
                $builder->where('expenses.approved_by', (int) $filters['approved_by']);
            }

            if ($filters['description'] !== '') {
                $builder->like('expenses.description', (string) $filters['description']);
            }

            if ($filters['amount'] !== '') {
                $builder->where('expenses.amount', (float) $filters['amount']);
            }

            if ($filters['expense_date'] !== '') {
                $dt = \DateTime::createFromFormat('d-m-Y', $filters['expense_date']);
                if ($dt) {
                    $builder->where('expenses.expense_date', $dt->format('Y-m-d'));
                }
            }

            $data['expenses'] = $builder
                ->orderBy('expenses.id', 'DESC')
                ->findAll();

            return $this->loadLayout('expense_list', $data);
        } catch (\Throwable $e) {
            return handle_exception($e, $this->myLogger, $this->response);
        }
    }

    /**
     * Create / update expense (AJAX)
     */
    public function save()
    {
        try {
            if ($this->request->getMethod() !== 'post') {
                return $this->response
                    ->setStatusCode(405)
                    ->setJSON([
                        'status'  => false,
                        'message' => 'Invalid request method',
                    ]);
            }

            $rawData = $this->request->getPost();
            $data    = sanitizeInputArrayAdvanced($rawData);

            $id = isset($data['id']) && $data['id'] !== '' ? (int) $data['id'] : null;

            $rules = [
                'client_id' => [
                    'rules'  => 'required|is_natural_no_zero',
                    'errors' => [
                        'required' => 'Client is required',
                    ],
                ],
                'client_policy_id' => [
                    'rules'  => 'required|is_natural_no_zero',
                    'errors' => [
                        'required' => 'Policy is required',
                    ],
                ],
                'description' => [
                    'rules'  => 'required|string|min_length[1]|max_length[2000]|regex_match[/^[a-zA-Z0-9\s\.\,\-\(\)\/\&\+]+$/]',
                    'errors' => [
                        'required'    => 'Description is required',
                        'min_length'  => 'Description cannot be empty',
                        'regex_match' => 'Description contains invalid characters.',
                    ],
                ],
                'expense_date' => [
                    'rules'  => 'required|valid_date[d-m-Y]',
                    'errors' => [
                        'required'   => 'Expense Date is required',
                        'valid_date' => 'Expense Date must be in DD-MM-YYYY format',
                    ],
                ],
                'approved_by' => [
                    'rules'  => 'required|is_natural_no_zero',
                    'errors' => [
                        'required' => 'Approved By is required',
                    ],
                ],
                'amount' => [
                    'rules'  => 'required|numeric|greater_than_equal_to[0]|less_than_equal_to[100000000]',
                    'errors' => [
                        'required'               => 'Amount is required',
                        'numeric'                => 'Amount must be numeric',
                        'greater_than_equal_to'  => 'Amount cannot be negative',
                        'less_than_equal_to'     => 'Amount cannot be greater than 100 Cr.',
                    ],
                ],
            ];

            if (! $this->validate($rules)) {
                return $this->response->setStatusCode(400)->setJSON([
                    'status'  => false,
                    'message' => 'Input validation failed',
                    'errors'  => $this->validator->getErrors(),
                ]);
            }

            $payload = [
                'client_id'        => (int) ($data['client_id'] ?? 0),
                'client_policy_id' => (int) ($data['client_policy_id'] ?? 0),
                'description'      => $data['description'] ?? null,
                'approved_by'      => (int) ($data['approved_by'] ?? 0),
                'amount'           => $data['amount'] ?? null,
                'is_active'        => 1,
            ];

            $expenseDate = $data['expense_date'] ?? null;
            if (! empty($expenseDate)) {
                $dt = \DateTime::createFromFormat('d-m-Y', $expenseDate);
                $payload['expense_date'] = $dt ? $dt->format('Y-m-d') : null;
            } else {
                $payload['expense_date'] = null;
            }

            if ($id === null) {
                $insertId = $this->expenseModel->insert($payload, true);
                $success  = ! empty($insertId);
                $id       = $insertId;
                $message  = $success
                    ? 'Expense created successfully'
                    : 'Unable to create expense. Please try again.';
            } else {
                $success = $this->expenseModel->update($id, $payload);
                $message = $success
                    ? 'Expense updated successfully'
                    : 'Unable to update expense. Please try again.';
            }

            return $this->response
                ->setStatusCode($success ? 200 : 400)
                ->setJSON([
                    'status'  => (bool) $success,
                    'message' => $message,
                    'id'      => $id,
                ]);
        } catch (\Throwable $e) {
            return handle_exception($e, $this->myLogger, $this->response);
        }
    }

    /**
     * Get single expense (AJAX)
     */
    public function getExpense($id = null)
    {
        try {
            $id = (int) $id;

            if (empty($id)) {
                return $this->response->setStatusCode(400)->setJSON([
                    'status'  => false,
                    'message' => 'Invalid expense id',
                ]);
            }

            $expense = $this->expenseModel
                ->select('
                    expenses.*,
                    clients.client_name,
                    clients.short_name,
                    client_policy.policy_no,
                    user_profiles.first_name AS approved_by_name
                ')
                ->join('clients', 'clients.id = expenses.client_id', 'left')
                ->join('client_policy', 'client_policy.id = expenses.client_policy_id', 'left')
                ->join('user_profiles', 'user_profiles.id = expenses.approved_by', 'left')
                ->where('expenses.id', $id)
                ->where('expenses.is_active', 1)
                ->first();

            if (empty($expense)) {
                return $this->response->setStatusCode(404)->setJSON([
                    'status'  => false,
                    'message' => 'Expense not found',
                ]);
            }

            return $this->response->setStatusCode(200)->setJSON([
                'status' => true,
                'data'   => $expense,
            ]);
        } catch (\Throwable $e) {
            return handle_exception($e, $this->myLogger, $this->response);
        }
    }

    /**
     * Soft delete expense (AJAX)
     */
    public function delete($id = null)
    {
        try {
            if ($this->request->getMethod() !== 'post') {
                return $this->response
                    ->setStatusCode(405)
                    ->setJSON([
                        'status'  => false,
                        'message' => 'Invalid request method',
                    ]);
            }

            $id = (int) $id;

            if (empty($id)) {
                return $this->response->setStatusCode(400)->setJSON([
                    'status'  => false,
                    'message' => 'Invalid expense id',
                ]);
            }

            $payload = [
                'is_active' => 0,
            ];

            $success = $this->expenseModel->update($id, $payload);

            return $this->response
                ->setStatusCode($success ? 200 : 400)
                ->setJSON([
                    'status'  => (bool) $success,
                    'message' => $success
                        ? 'Expense deleted successfully'
                        : 'Unable to delete expense. Please try again.',
                ]);
        } catch (\Throwable $e) {
            return handle_exception($e, $this->myLogger, $this->response);
        }
    }

    /**
     * Get policies by client for dropdown (AJAX)
     */
    public function clientPolicies()
    {
        try {
            $clientId = (int) ($this->request->getGet('client_id') ?? 0);

            if (empty($clientId)) {
                return $this->response->setStatusCode(400)->setJSON([
                    'status'  => false,
                    'message' => 'Client is required',
                ]);
            }

            $policies = $this->clientPolicyModel
                ->select('client_policy.id, client_policy.policy_no, policy_type.policy_type')
                ->join('policy_type', 'policy_type.id = client_policy.policy_type_id AND policy_type.is_active = 1')
                ->where('client_policy.client_id', $clientId)
                ->where('client_policy.is_active', 1)
                ->orderBy('client_policy.id', 'ASC')
                ->findAll();

            return $this->response->setStatusCode(200)->setJSON([
                'status' => true,
                'data'   => $policies,
            ]);
        } catch (\Throwable $e) {
            return handle_exception($e, $this->myLogger, $this->response);
        }
    }
}