<?php

declare(strict_types=1);

namespace App\Controllers;

use App\Models\Employee;
use App\Repositories\EmployeeRepository;
use App\ViewModels\EmployeeFormViewModel;
use Core\Controller;
use Core\Request;
use Core\Validator;

class EmployeeController extends Controller
{
    public function index()
    {
        $request = Request::capture();
        $viewModel = $this->buildViewModel((string) $request->input('search', ''));
        $viewModel->saved = $request->input('saved') === '1';

        return $this->view('employees.create', [
            'model' => $viewModel,
            'pageTitle' => $viewModel->title,
        ]);
    }

    public function store()
    {
        $request = Request::capture();
        $form = $this->sanitizeFormData($request);
        $errors = $this->validateForm($form, $request);

        if (empty($errors) && $this->employees()->findByEmail($form['email']) !== null) {
            $errors['email'][] = 'That email address is already in use.';
        }

        if (!empty($errors)) {
            $viewModel = $this->buildViewModel();
            $viewModel->form = $form;
            $viewModel->errors = $errors;

            if ($this->isHtmxRequest($request)) {
                return $this->fragment('employees.partials.form', [
                    'model' => $viewModel,
                ]);
            }

            return $this->view('employees.create', [
                'model' => $viewModel,
                'pageTitle' => $viewModel->title,
            ]);
        }

        $employee = new Employee();
        $employee->firstName = $form['first_name'];
        $employee->lastName = $form['last_name'];
        $employee->email = $form['email'];
        $employee->department = $form['department'];
        $employee->jobTitle = $form['job_title'];
        $employee->startDate = $form['start_date'];

        $this->employees()->create($employee);

        if ($this->isHtmxRequest($request)) {
            $viewModel = $this->buildViewModel();
            $viewModel->saved = true;

            return $this->fragment('employees.partials.form', [
                'model' => $viewModel,
            ], 200, [
                'HX-Trigger' => json_encode(['employees-changed' => true]),
            ]);
        }

        return $this->redirect('/employees?saved=1');
    }

    public function create()
    {
        return $this->redirect('/employees');
    }

    public function summary()
    {
        $request = Request::capture();
        $viewModel = $this->buildViewModel((string) $request->input('search', ''));

        return $this->fragment('employees.partials.summary', [
            'model' => $viewModel,
        ]);
    }

    public function data()
    {
        $request = Request::capture();
        $search = trim((string) $request->input('search', ''));
        $rows = $this->employees()->search($search);

        $data = array_map(
            static function (array $row): array {
                return [
                    'id' => (int) $row['id'],
                    'full_name' => trim($row['first_name'] . ' ' . $row['last_name']),
                    'first_name' => (string) $row['first_name'],
                    'last_name' => (string) $row['last_name'],
                    'email' => (string) $row['email'],
                    'department' => (string) $row['department'],
                    'job_title' => (string) $row['job_title'],
                    'start_date' => (string) $row['start_date'],
                    'created_at' => (string) $row['created_at'],
                ];
            },
            $rows
        );

        return $this->json($data);
    }

    /**
     * @return array<string, string>
     */
    private function sanitizeFormData(Request $request): array
    {
        return [
            'first_name' => trim((string) $request->input('first_name', '')),
            'last_name' => trim((string) $request->input('last_name', '')),
            'email' => trim((string) $request->input('email', '')),
            'department' => trim((string) $request->input('department', '')),
            'job_title' => trim((string) $request->input('job_title', '')),
            'start_date' => trim((string) $request->input('start_date', '')),
        ];
    }

    /**
     * @param array<string, string> $form
     * @return array<string, list<string>>
     */
    private function validateForm(array $form, Request $request): array
    {
        $validator = new Validator();

        $validator
            ->required('first_name', $form['first_name'], 'First name is required.')
            ->maxLength('first_name', $form['first_name'], 100, 'First name must be 100 characters or fewer.')
            ->required('last_name', $form['last_name'], 'Last name is required.')
            ->maxLength('last_name', $form['last_name'], 100, 'Last name must be 100 characters or fewer.')
            ->required('email', $form['email'], 'Email is required.')
            ->maxLength('email', $form['email'], 255, 'Email must be 255 characters or fewer.')
            ->required('department', $form['department'], 'Department is required.')
            ->maxLength('department', $form['department'], 100, 'Department must be 100 characters or fewer.')
            ->required('job_title', $form['job_title'], 'Job title is required.')
            ->maxLength('job_title', $form['job_title'], 150, 'Job title must be 150 characters or fewer.')
            ->required('start_date', $form['start_date'], 'Start date is required.');

        $errors = $validator->errors();

        if (!verify_csrf_token((string) $request->input('_token', ''))) {
            $errors['_token'][] = 'Your form session expired. Please refresh the page and try again.';
        }

        if ($form['email'] !== '' && filter_var($form['email'], FILTER_VALIDATE_EMAIL) === false) {
            $errors['email'][] = 'Enter a valid email address.';
        }

        if ($form['start_date'] !== '' && !$this->isValidDate($form['start_date'])) {
            $errors['start_date'][] = 'Enter a valid start date.';
        }

        return $errors;
    }

    private function isValidDate(string $value): bool
    {
        $date = \DateTimeImmutable::createFromFormat('Y-m-d', $value);

        return $date !== false && $date->format('Y-m-d') === $value;
    }

    private function employees(): EmployeeRepository
    {
        return new EmployeeRepository(database());
    }

    private function isHtmxRequest(Request $request): bool
    {
        return strtolower((string) $request->server('HTTP_HX_REQUEST', '')) === 'true';
    }

    private function buildViewModel(string $search = ''): EmployeeFormViewModel
    {
        $viewModel = new EmployeeFormViewModel();
        $viewModel->search = trim($search);

        $employees = $this->employees()->search($viewModel->search);
        $newestEmployee = $this->employees()->newestMatching($viewModel->search);

        $viewModel->employees = array_slice($employees, 0, 5);
        $viewModel->newestEmployee = $newestEmployee;
        $viewModel->summary = [
            'employee_count' => $this->employees()->countMatching($viewModel->search),
            'department_count' => $this->employees()->countDepartments($viewModel->search),
            'latest_start_date' => $newestEmployee['start_date'] ?? 'N/A',
        ];

        return $viewModel;
    }
}