<?php

namespace App\Http\Controllers\Api;

use Carbon\Carbon;
use Symfony\Component\HttpFoundation\Response;

class TimeController extends BaseApiController
{
    protected string $defaultUserTimezone = 'America/New_York';
    protected string $serverTimezone;

    public function __construct()
    {
        parent::__construct();
        $this->serverTimezone = config('app.timezone', 'UTC');
    }

    protected function detectUserTimezone(): string
    {
        $header = $this->laravelRequest->headers->get('X-Timezone');
        if (!empty($header) && in_array($header, timezone_identifiers_list(), true)) {
            return $header;
        }

        $param = $this->laravelRequest->get('timezone');
        if (!empty($param) && in_array($param, timezone_identifiers_list(), true)) {
            return $param;
        }

        return $this->defaultUserTimezone;
    }

    public function convert()
    {
        $data = $this->payloadData();
        if (empty($data['time']) || empty($data['direction'])) {
            return $this->respondValidationError(['time' => 'Required', 'direction' => 'Required']);
        }

        $userTz = $this->detectUserTimezone();
        $time = trim((string) $data['time']);
        $direction = strtolower((string) $data['direction']);

        try {
            if ($direction === 'toutc') {
                $converted = Carbon::parse($time, $userTz)
                    ->setTimezone('UTC')
                    ->toDateTimeString();

                return $this->success([
                    'user_timezone'   => $userTz,
                    'server_timezone' => 'UTC',
                    'original_time'   => $time,
                    'converted_time'  => $converted,
                ], 'Conversion completed');
            }

            if ($direction === 'tolocal') {
                $converted = Carbon::parse($time, 'UTC')
                    ->setTimezone($userTz)
                    ->toDateTimeString();

                return $this->success([
                    'user_timezone'   => $userTz,
                    'server_timezone' => 'UTC',
                    'original_time'   => $time,
                    'converted_time'  => $converted,
                ], 'Conversion completed');
            }

            return $this->respondValidationError(['direction' => 'Must be toUTC or toLocal']);
        } catch (\Throwable $e) {
            return $this->respondError('Failed to convert time: ' . $e->getMessage(), Response::HTTP_INTERNAL_SERVER_ERROR);
        }
    }

    public function now()
    {
        $userTz = $this->detectUserTimezone();

        try {
            $local = Carbon::now($userTz)->toDateTimeString();
            $utc   = Carbon::now('UTC')->toDateTimeString();

            return $this->success([
                'user_timezone'   => $userTz,
                'server_timezone' => 'UTC',
                'local_time'      => $local,
                'utc_time'        => $utc,
            ], 'Current time retrieved');
        } catch (\Throwable $e) {
            return $this->respondError('Failed to determine current time', Response::HTTP_INTERNAL_SERVER_ERROR);
        }
    }
}