<?php
     $file = 'counter.dat';

// 读取并自增
$counter = (int)@file_get_contents($file);
$counter++;

// 使用 LOCK_EX 防止并发写入冲突
file_put_contents($file, $counter, LOCK_EX); 
 ?>
<?php
// 天气查询 API - 使用国内平台数据
header('Content-Type: application/json; charset=utf-8');
header('Access-Control-Allow-Origin: *');

// 获取参数
$city = $_GET['city'] ?? $_GET['q'] ?? null;
$type = $_GET['type'] ?? 'json'; // json, xml 
$lang = $_GET['lang'] ?? 'zh'; // zh, en

// 验证参数
if (!$city) {
    http_response_code(400);
    echo json_encode([
        'status' => 'error',
        'code' => 400,
        'message' => '缺少必要参数: city (城市名称)',
        'example' => '/api/tq/?city=北京&type=json&lang=zh'
    ], JSON_UNESCAPED_UNICODE);
    exit;
}

// 非法字符检查
if (!preg_match('/^[\u4e00-\u9fff\w\s\-]+$/u', $city) || strlen($city) > 50) {
    http_response_code(400);
    echo json_encode([
        'status' => 'error',
        'code' => 400,
        'message' => '无效的城市名称'
    ], JSON_UNESCAPED_UNICODE);
    exit;
}

$result = null;
$error = null;

// 方案1: wttr.in 天气服务 (支持中文)
// 方案2: 使用中国天气网数据源

// 尝试方案1: wttr.in 天气服务 (支持中文)
$url = "https://wttr.in/" . urlencode($city) . "?format=j1&lang=" . ($lang === 'en' ? 'en' : 'zh-CN');

$ch = curl_init();
curl_setopt($ch, CURLOPT_URL, $url);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
curl_setopt($ch, CURLOPT_TIMEOUT, 10);
curl_setopt($ch, CURLOPT_USERAGENT, 'Mozilla/5.0 (Windows NT 10.0; Win64; x64) QuickAPI/1.0');
curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, false);
curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, false);

$response = curl_exec($ch);
$http_code = curl_getinfo($ch, CURLINFO_HTTP_CODE);
curl_close($ch);

if ($http_code == 200 && $response) {
    $data = json_decode($response, true);
    
    if ($data && isset($data['current_condition'])) {
        $current = $data['current_condition'][0];
        $desc = $current['desc'] ?? [];
        
        $result = [
            'status' => 'success',
            'code' => 200,
            'city' => $city,
            'current' => [
                'temperature' => (float)$current['temp_C'] ?? null,
                'temperature_f' => (float)$current['temp_F'] ?? null,
                'feels_like' => (float)$current['FeelsLikeC'] ?? null,
                'condition' => is_array($desc) ? ($desc[$lang === 'en' ? 'en' : 'zh-CN'] ?? $desc[0] ?? 'Unknown') : 'Unknown',
                'humidity' => (int)$current['humidity'] ?? null,
                'wind_speed' => (float)$current['windspeedKmph'] ?? null,
                'wind_speed_ms' => (float)$current['windspeedKmph'] / 3.6 ?? null,
                'wind_direction' => $current['winddir16Point'] ?? null,
                'pressure' => (int)$current['pressure'] ?? null,
                'precipitation' => (float)$current['precipMM'] ?? null,
                'visibility' => (float)$current['visibility'] ?? null,
                'uv_index' => (int)$current['uvIndex'] ?? null,
                'cloud_cover' => (int)$current['cloudcover'] ?? null
            ],
            'forecast' => [],
            'source' => 'wttr.in',
            'updated_at' => date('Y-m-d H:i:s')
        ];
        
        // 添加预报数据 (如果可用)
        if (isset($data['weather']) && is_array($data['weather'])) {
            foreach ($data['weather'] as $day_idx => $day) {
                if ($day_idx >= 3) break; // 只显示3天预报
                
                $forecast_avg = $day['avgtemp_c'] ?? null;
                $forecast_max = $day['maxtemp_c'] ?? null;
                $forecast_min = $day['mintemp_c'] ?? null;
                $forecast_desc = $day['hourly'][0]['desc'] ?? [];
                
                $result['forecast'][] = [
                    'date' => $day['date'] ?? null,
                    'avg_temp' => (float)$forecast_avg,
                    'max_temp' => (float)$forecast_max,
                    'min_temp' => (float)$forecast_min,
                    'condition' => is_array($forecast_desc) ? ($forecast_desc[$lang === 'en' ? 'en' : 'zh-CN'] ?? $forecast_desc[0] ?? 'Unknown') : 'Unknown',
                    'avg_humidity' => (int)$day['avghumidity'] ?? null,
                    'total_snow' => (float)$day['totalSnow_cm'] ?? null,
                    'uv_index' => (int)$day['uvIndex'] ?? null
                ];
            }
        }
    } else {
        $error = '无法解析天气数据';
    }
} else {
    $error = '无法连接到天气服务或城市不存在';
}

// 如果主方案失败,尝试方案2: 心知天气 API (中国天气网数据)
if (!$result) {
    // 心知天气免费API - 无需key即可使用基础功能
    $url2 = "https://api.seniverse.com/v1/now.json?location=" . urlencode($city) . "&language=" . ($lang === 'en' ? 'en' : 'zh-Hans');
    
    $ch2 = curl_init();
    curl_setopt($ch2, CURLOPT_URL, $url2);
    curl_setopt($ch2, CURLOPT_RETURNTRANSFER, true);
    curl_setopt($ch2, CURLOPT_TIMEOUT, 10);
    curl_setopt($ch2, CURLOPT_USERAGENT, 'Mozilla/5.0 QuickAPI/1.0');
    curl_setopt($ch2, CURLOPT_SSL_VERIFYPEER, false);
    
    $response2 = curl_exec($ch2);
    $http_code2 = curl_getinfo($ch2, CURLINFO_HTTP_CODE);
    curl_close($ch2);
    
    if ($http_code2 == 200 && $response2) {
        $data2 = json_decode($response2, true);
        
        if ($data2 && isset($data2['results']) && count($data2['results']) > 0) {
            $results = $data2['results'][0];
            $location = $results['location'];
            $now = $results['now'];
            
            $result = [
                'status' => 'success',
                'code' => 200,
                'city' => $location['name'] ?? $city,
                'region' => $location['country'] ?? null,
                'coordinates' => [
                    'latitude' => (float)$location['lat'] ?? null,
                    'longitude' => (float)$location['lon'] ?? null
                ],
                'current' => [
                    'temperature' => (float)$now['temperature'] ?? null,
                    'feels_like' => (float)$now['feels_like'] ?? null,
                    'condition' => $now['text'] ?? 'Unknown',
                    'condition_code' => $now['code'] ?? null,
                    'wind_speed' => (float)$now['wind_speed'] ?? null,
                    'wind_speed_kph' => ((float)$now['wind_speed'] * 3.6) ?? null,
                    'wind_direction' => $now['wind_direction'] ?? null,
                    'wind_direction_code' => $now['wind_direction_code'] ?? null,
                    'humidity' => (int)$now['humidity'] ?? null,
                    'visibility' => (float)$now['visibility'] ?? null,
                    'pressure' => (int)$now['pressure'] ?? null
                ],
                'source' => '心知天气(中国天气数据)',
                'updated_at' => date('Y-m-d H:i:s')
            ];
        }
    }
}

// 如果仍未获得数据,尝试方案3: 和风天气 API
if (!$result) {
    // 和风天气免费API
    $url3 = "https://devapi.qweather.com/v7/weather/now?location=" . urlencode($city) . "&lang=" . ($lang === 'en' ? 'en' : 'zh');
    
    $ch3 = curl_init();
    curl_setopt($ch3, CURLOPT_URL, $url3);
    curl_setopt($ch3, CURLOPT_RETURNTRANSFER, true);
    curl_setopt($ch3, CURLOPT_TIMEOUT, 10);
    curl_setopt($ch3, CURLOPT_USERAGENT, 'Mozilla/5.0 QuickAPI/1.0');
    curl_setopt($ch3, CURLOPT_SSL_VERIFYPEER, false);
    
    $response3 = curl_exec($ch3);
    $http_code3 = curl_getinfo($ch3, CURLINFO_HTTP_CODE);
    curl_close($ch3);
    
    if ($http_code3 == 200 && $response3) {
        $data3 = json_decode($response3, true);
        
        if ($data3 && isset($data3['now'])) {
            $now = $data3['now'];
            
            $result = [
                'status' => 'success',
                'code' => 200,
                'city' => $data3['fxLink'] ? substr($data3['fxLink'], strrpos($data3['fxLink'], '/') + 1) : $city,
                'current' => [
                    'temperature' => (int)$now['temp'] ?? null,
                    'feels_like' => (int)$now['feelsLike'] ?? null,
                    'condition_code' => $now['icon'] ?? null,
                    'condition' => $now['text'] ?? 'Unknown',
                    'wind_speed' => (float)$now['windSpeed'] ?? null,
                    'wind_direction' => $now['windDir'] ?? null,
                    'wind_direction_code' => (int)$now['wind_degree'] ?? null,
                    'humidity' => (int)$now['humidity'] ?? null,
                    'pressure' => (int)$now['pressure'] ?? null,
                    'visibility' => (int)$now['vis'] ?? null,
                    'dew_point' => (int)$now['dewPoint'] ?? null
                ],
                'source' => '和风天气(中国天气数据)',
                'updated_at' => date('Y-m-d H:i:s')
            ];
        }
    }
}

// 返回结果
if ($result) {
    if ($type === 'xml' || $type === 'XML') {
        header('Content-type: application/xml; charset=UTF-8');
        echo arrayToXml($result, null, null, 'weather');
    } else {
        echo json_encode($result, JSON_UNESCAPED_UNICODE | JSON_PRETTY_PRINT);
    }
} else {
    http_response_code(500);
    echo json_encode([
        'status' => 'error',
        'code' => 500,
        'message' => $error ?? '天气服务暂时不可用',
        'tips' => '请尝试使用其他城市名称或稍后再试'
    ], JSON_UNESCAPED_UNICODE);
}

// 数组转XML函数
function arrayToXml($arr, $dom = null, $node = null, $root = 'root', $cdata = false) {
    if (!$dom) {
        $dom = new DOMDocument('1.0', 'utf-8');
    }
    if (!$node) {
        $node = $dom->createElement($root);
        $dom->appendChild($node);
    }
    
    foreach ($arr as $key => $value) {
        if (is_numeric($key)) {
            $key = 'item';
        }
        $child_node = $dom->createElement($key);
        $node->appendChild($child_node);
        
        if (!is_array($value)) {
            if (!$cdata) {
                $data = $dom->createTextNode((string)$value);
            } else {
                $data = $dom->createCDATASection((string)$value);
            }
            $child_node->appendChild($data);
        } else {
            arrayToXml($value, $dom, $child_node, $root, $cdata);
        }
    }
    
    return $dom->saveXML();
}
?>