<?php
/**
 * 发现页随机数据接口
 * 
 * @file      api_discover.php
 * @author    AI Assistant
 * @date      2026-04-12
 * @version   1.1.0
 * @desc      提供随机数据用于首页/发现页瀑布流，支持响应式布局
 *             同一客户端多次请求返回不重复数据，30分钟后重置
 * @lastUpdate 2026-04-12 添加已返回ID排除机制，避免重复数据
 */

$startTime = microtime(true);

require '../zb_system/function/c_system_base.php';
$zbp->Load();

require_once 'cache.php';
require_once 'response.php';

header('Access-Control-Allow-Origin: *');
header('Access-Control-Allow-Methods: GET, POST, OPTIONS');
header('Cache-Control: public, max-age=5');

if ($_SERVER['REQUEST_METHOD'] === 'OPTIONS') {
    http_response_code(200);
    exit;
}

$method = $_SERVER['REQUEST_METHOD'];

if ($method === 'GET') {
    $params = $_GET;
} elseif ($method === 'POST') {
    $input = file_get_contents('php://input');
    $jsonData = json_decode($input, true);
    if (is_array($jsonData)) {
        $params = $jsonData;
    } else {
        $params = $_POST;
    }
} else {
    $params = array();
}

$format = ApiResponse::getFormat();
$forceRefresh = isset($params['_refresh']) && $params['_refresh'] === '1';

$clientIP = getClientIP();

header('X-Cache: MISS');

$counts = calculateCounts($params);

$data = array(
    'recipes' => getRandomRecipes($counts['recipe'], $clientIP),
    'ingredients' => getRandomIngredients($counts['ingredient'], $clientIP),
    'categories' => getRandomCategories($counts['category'], $clientIP),
    'tags' => getRandomTags($counts['tag'], $clientIP),
    'nutrition_types' => getNutritionTypes($counts['nutrition'], $clientIP),
    'meal_times' => getMealTimes($counts['meal_time'])
);

$recipeIds = array_column($data['recipes'], 'id');
$ingredientIds = array_column($data['ingredients'], 'id');
$categoryIds = array_column($data['categories'], 'id');
$tagIds = array_column($data['tags'], 'id');
$nutritionNames = array_column($data['nutrition_types'], 'name');

if (!empty($recipeIds)) {
    ApiCache::addDiscoverReturnedIds($clientIP, 'recipe', $recipeIds);
}
if (!empty($ingredientIds)) {
    ApiCache::addDiscoverReturnedIds($clientIP, 'ingredient', $ingredientIds);
}
if (!empty($categoryIds)) {
    ApiCache::addDiscoverReturnedIds($clientIP, 'category', $categoryIds);
}
if (!empty($tagIds)) {
    ApiCache::addDiscoverReturnedIds($clientIP, 'tag', $tagIds);
}
if (!empty($nutritionNames)) {
    ApiCache::addDiscoverReturnedIds($clientIP, 'nutrition', $nutritionNames);
}

$result = array(
    'code' => 200,
    'message' => 'success',
    'data' => $data,
    'meta' => array(
        'cache_status' => 'fresh',
        'counts' => $counts
    )
);

$result['_query_time'] = round((microtime(true) - $startTime) * 1000, 2) . 'ms';

ApiResponse::output($result, $format);
exit;

/**
 * 获取客户端IP
 */
function getClientIP() {
    $ip = '';
    if (!empty($_SERVER['HTTP_CLIENT_IP'])) {
        $ip = $_SERVER['HTTP_CLIENT_IP'];
    } elseif (!empty($_SERVER['HTTP_X_FORWARDED_FOR'])) {
        $ip = explode(',', $_SERVER['HTTP_X_FORWARDED_FOR'])[0];
    } elseif (!empty($_SERVER['REMOTE_ADDR'])) {
        $ip = $_SERVER['REMOTE_ADDR'];
    }
    return trim($ip) ?: 'unknown';
}

/**
 * 计算各类型数量
 */
function calculateCounts($params) {
    $total = isset($params['total']) ? min((int) $params['total'], 100) : 50;
    
    $ratios = array(
        'recipe' => 0.75,
        'ingredient' => 0.03,
        'category' => 0.10,
        'tag' => 0.03,
        'nutrition' => 0.02,
        'meal_time' => 0.02
    );
    
    $counts = array();
    $specifiedTotal = 0;
    $specifiedTypes = array();
    
    foreach ($ratios as $type => $ratio) {
        $paramName = $type === 'nutrition' ? 'nutrition' : $type;
        if (isset($params[$paramName]) && (int) $params[$paramName] > 0) {
            $counts[$type] = min((int) $params[$paramName], 80);
            $specifiedTotal += $counts[$type];
            $specifiedTypes[] = $type;
        }
    }
    
    if (count($specifiedTypes) === count($ratios)) {
        return $counts;
    }
    
    $remaining = $total - $specifiedTotal;
    $remainingTypes = array_diff(array_keys($ratios), $specifiedTypes);
    
    $remainingRatioSum = 0;
    foreach ($remainingTypes as $type) {
        $remainingRatioSum += $ratios[$type];
    }
    
    foreach ($remainingTypes as $type) {
        $adjustedRatio = $remainingRatioSum > 0 ? $ratios[$type] / $remainingRatioSum : 1 / count($remainingTypes);
        $counts[$type] = max(1, round($remaining * $adjustedRatio));
    }
    
    return $counts;
}

/**
 * 获取随机菜品
 */
function getRandomRecipes($limit, $clientIP = '') {
    global $zbp;
    
    if ($limit <= 0) return array();
    
    $tablePost = $zbp->db->dbpre . 'post';
    $tableCategory = $zbp->db->dbpre . 'category';
    $tablePostStat = $zbp->db->dbpre . 'post_stat';
    $tableIdMap = $zbp->db->dbpre . 'recipe_id_map';
    
    $excludeIds = array();
    if (!empty($clientIP)) {
        $excludeIds = ApiCache::getDiscoverReturnedIds($clientIP, 'recipe');
    }
    
    $whereClause = "p.log_Type = 0 AND p.log_Status = 0";
    if (!empty($excludeIds)) {
        $excludeIdsStr = implode(',', array_map('intval', $excludeIds));
        $whereClause .= " AND p.log_ID NOT IN ($excludeIdsStr)";
    }
    
    $sql = "SELECT p.log_ID, p.log_Title, p.log_CateID, p.log_ViewNums,
                   c.cate_Name,
                   s.rate_nums, s.rate_score,
                   m.old_id
            FROM $tablePost p
            LEFT JOIN $tableCategory c ON p.log_CateID = c.cate_ID
            LEFT JOIN $tablePostStat s ON p.log_ID = s.log_id
            LEFT JOIN $tableIdMap m ON p.log_ID = m.new_log_id
            WHERE $whereClause
            ORDER BY RAND()
            LIMIT $limit";
    
    $results = $zbp->db->Query($sql);
    
    if (empty($results) && !empty($excludeIds)) {
        ApiCache::clearDiscoverReturnedIds($clientIP, 'recipe');
        return getRandomRecipes($limit, $clientIP);
    }
    
    $list = array();
    foreach ($results as $row) {
        $rateNums = (int) ($row['rate_nums'] ?? 0);
        $rateScore = (float) ($row['rate_score'] ?? 0);
        $rating = ApiResponse::getRatingSummary($rateScore, $rateNums);
        
        $cover = '';
        if (!empty($row['old_id'])) {
            $cover = 'http://eat.wktyl.com/api/assets/pic/' . $row['old_id'] . 'a.jpg';
        }
        
        $list[] = array(
            'id' => (int) $row['log_ID'],
            'title' => $row['log_Title'],
            'cover' => $cover,
            'category' => array(
                'id' => (int) $row['log_CateID'],
                'name' => $row['cate_Name'] ?? ''
            ),
            'rating' => $rating,
            'views' => (int) $row['log_ViewNums']
        );
    }
    
    return $list;
}

/**
 * 获取随机食材
 */
function getRandomIngredients($limit, $clientIP = '') {
    global $zbp;
    
    if ($limit <= 0) return array();
    
    $tableIngredient = $zbp->db->dbpre . 'ingredient_detail';
    $tableCategory = $zbp->db->dbpre . 'category';
    
    $excludeIds = array();
    if (!empty($clientIP)) {
        $excludeIds = ApiCache::getDiscoverReturnedIds($clientIP, 'ingredient');
    }
    
    $whereClause = "1=1";
    if (!empty($excludeIds)) {
        $excludeIdsStr = implode(',', array_map('intval', $excludeIds));
        $whereClause .= " AND i.ingredient_id NOT IN ($excludeIdsStr)";
    }
    
    $sql = "SELECT i.ingredient_id, i.name, i.cate_ID, i.allergen, i.introduction,
                   c.cate_Name
            FROM $tableIngredient i
            LEFT JOIN $tableCategory c ON i.cate_ID = c.cate_ID
            WHERE $whereClause
            ORDER BY RAND()
            LIMIT $limit";
    
    $results = $zbp->db->Query($sql);
    
    if (empty($results) && !empty($excludeIds)) {
        ApiCache::clearDiscoverReturnedIds($clientIP, 'ingredient');
        return getRandomIngredients($limit, $clientIP);
    }
    
    $list = array();
    foreach ($results as $row) {
        $allergen = array();
        if (!empty($row['allergen'])) {
            $decoded = json_decode($row['allergen'], true);
            $allergen = is_array($decoded) ? $decoded : array($row['allergen']);
        }
        
        $intro = $row['introduction'] ?? '';
        if (mb_strlen($intro) > 100) {
            $intro = mb_substr($intro, 0, 100) . '...';
        }
        
        $list[] = array(
            'id' => (int) $row['ingredient_id'],
            'name' => $row['name'],
            'category' => array(
                'id' => (int) $row['cate_ID'],
                'name' => $row['cate_Name'] ?? ''
            ),
            'allergen' => $allergen,
            'intro' => $intro
        );
    }
    
    return $list;
}

/**
 * 获取随机分类
 */
function getRandomCategories($limit, $clientIP = '') {
    global $zbp;
    
    if ($limit <= 0) return array();
    
    $tableCategory = $zbp->db->dbpre . 'category';
    $tableIngredient = $zbp->db->dbpre . 'ingredient_detail';
    
    $excludeIds = array();
    if (!empty($clientIP)) {
        $excludeIds = ApiCache::getDiscoverReturnedIds($clientIP, 'category');
    }
    
    $excludeClause = '';
    if (!empty($excludeIds)) {
        $excludeIdsStr = implode(',', array_map('intval', $excludeIds));
        $excludeClause = " AND cate_ID NOT IN ($excludeIdsStr)";
    }
    
    $recipeLimit = max(1, ceil($limit * 0.6));
    $ingredientLimit = $limit - $recipeLimit;
    
    $results = array();
    
    $sqlRecipe = "SELECT cate_ID, cate_Name, cate_Count, cate_ParentID
                  FROM $tableCategory
                  WHERE cate_ID > 10 AND cate_ID < 1000 AND cate_ParentID != 11 $excludeClause
                  ORDER BY RAND()
                  LIMIT $recipeLimit";
    $recipeResults = $zbp->db->Query($sqlRecipe);
    $results = array_merge($results, $recipeResults);
    
    $sqlIngredient = "SELECT cate_ID, cate_Name, cate_Count, cate_ParentID
                      FROM $tableCategory
                      WHERE cate_ID >= 1000 $excludeClause
                      ORDER BY RAND()
                      LIMIT $ingredientLimit";
    $ingredientResults = $zbp->db->Query($sqlIngredient);
    $results = array_merge($results, $ingredientResults);
    
    if (empty($results) && !empty($excludeIds)) {
        ApiCache::clearDiscoverReturnedIds($clientIP, 'category');
        return getRandomCategories($limit, $clientIP);
    }
    
    $ingredientCounts = array();
    $cateIds = array_column($results, 'cate_ID');
    if (!empty($cateIds)) {
        $cateIdsStr = implode(',', array_map('intval', $cateIds));
        $sqlIngredientCount = "SELECT cate_ID, COUNT(*) as cnt FROM $tableIngredient WHERE cate_ID IN ($cateIdsStr) GROUP BY cate_ID";
        $ingredientCountResults = $zbp->db->Query($sqlIngredientCount);
        foreach ($ingredientCountResults as $row) {
            $ingredientCounts[$row['cate_ID']] = (int) $row['cnt'];
        }
    }
    
    $parentIds = array_unique(array_filter(array_column($results, 'cate_ParentID')));
    $parentNames = array();
    if (!empty($parentIds)) {
        $parentIdsStr = implode(',', array_map('intval', $parentIds));
        $sqlParent = "SELECT cate_ID, cate_Name FROM $tableCategory WHERE cate_ID IN ($parentIdsStr)";
        $parentResults = $zbp->db->Query($sqlParent);
        foreach ($parentResults as $row) {
            $parentNames[$row['cate_ID']] = $row['cate_Name'];
        }
    }
    
    $list = array();
    foreach ($results as $row) {
        $type = 'recipe';
        if ($row['cate_ParentID'] >= 1000 || $row['cate_ID'] >= 1000) {
            $type = 'ingredient';
        } elseif ($row['cate_ParentID'] == 11) {
            $type = 'recipe_main';
        }
        
        $recipeCount = (int) ($row['cate_Count'] ?? 0);
        $ingredientCount = isset($ingredientCounts[$row['cate_ID']]) ? $ingredientCounts[$row['cate_ID']] : 0;
        $parentId = (int) $row['cate_ParentID'];
        $parentName = isset($parentNames[$parentId]) ? $parentNames[$parentId] : '';
        
        $list[] = array(
            'id' => (int) $row['cate_ID'],
            'name' => $row['cate_Name'],
            'type' => $type,
            'recipe_count' => $recipeCount,
            'ingredient_count' => $ingredientCount,
            'count' => $type === 'ingredient' ? $ingredientCount : $recipeCount,
            'parent_id' => $parentId,
            'parent_name' => $parentName
        );
    }
    
    shuffle($list);
    
    return $list;
}

/**
 * 获取随机标签
 */
function getRandomTags($limit, $clientIP = '') {
    global $zbp;
    
    if ($limit <= 0) return array();
    
    $tableTag = $zbp->db->dbpre . 'tag';
    
    $excludeIds = array();
    if (!empty($clientIP)) {
        $excludeIds = ApiCache::getDiscoverReturnedIds($clientIP, 'tag');
    }
    
    $whereClause = "tag_Alias IN ('口味', '做法')";
    if (!empty($excludeIds)) {
        $excludeIdsStr = implode(',', array_map('intval', $excludeIds));
        $whereClause .= " AND tag_ID NOT IN ($excludeIdsStr)";
    }
    
    $sql = "SELECT tag_ID, tag_Name, tag_Alias, tag_Count
            FROM $tableTag
            WHERE $whereClause
            ORDER BY RAND()
            LIMIT $limit";
    
    $results = $zbp->db->Query($sql);
    
    if (empty($results) && !empty($excludeIds)) {
        ApiCache::clearDiscoverReturnedIds($clientIP, 'tag');
        return getRandomTags($limit, $clientIP);
    }
    
    $list = array();
    foreach ($results as $row) {
        $type = 'taste';
        if ($row['tag_Alias'] === '做法') {
            $type = 'cooking';
        }
        
        $list[] = array(
            'id' => (int) $row['tag_ID'],
            'name' => $row['tag_Name'],
            'type' => $type,
            'count' => (int) ($row['tag_Count'] ?? 0)
        );
    }
    
    return $list;
}

/**
 * 获取营养成分类型
 */
function getNutritionTypes($limit, $clientIP = '') {
    global $zbp;
    
    if ($limit <= 0) return array();
    
    $tableNutrition = $zbp->db->dbpre . 'recipe_nutrition';
    
    $excludeNames = array();
    if (!empty($clientIP)) {
        $excludeNames = ApiCache::getDiscoverReturnedIds($clientIP, 'nutrition');
    }
    
    $whereClause = "name IS NOT NULL AND name != ''";
    if (!empty($excludeNames)) {
        $escapedNames = array_map(function($name) use ($zbp) {
            return $zbp->db->EscapeString($name);
        }, $excludeNames);
        $excludeNamesStr = "'" . implode("','", $escapedNames) . "'";
        $whereClause .= " AND name NOT IN ($excludeNamesStr)";
    }
    
    $sql = "SELECT DISTINCT name, unit
            FROM $tableNutrition
            WHERE $whereClause
            ORDER BY RAND()
            LIMIT $limit";
    
    $results = $zbp->db->Query($sql);
    
    if (empty($results) && !empty($excludeNames)) {
        ApiCache::clearDiscoverReturnedIds($clientIP, 'nutrition');
        return getNutritionTypes($limit, $clientIP);
    }
    
    $list = array();
    foreach ($results as $row) {
        $list[] = array(
            'name' => $row['name'],
            'unit' => $row['unit'] ?? ''
        );
    }
    
    return $list;
}

/**
 * 获取用餐时段
 */
function getMealTimes($limit) {
    global $zbp;
    
    if ($limit <= 0) return array();
    
    $tablePost = $zbp->db->dbpre . 'post';
    
    $sql = "SELECT log_Intro FROM $tablePost 
            WHERE log_Type = 0 AND log_Status = 0 
              AND log_Intro IS NOT NULL AND log_Intro != ''
            LIMIT 500";
    
    $results = $zbp->db->Query($sql);
    
    $mealTimes = array();
    foreach ($results as $row) {
        $times = preg_split('/[、，,]/u', $row['log_Intro']);
        foreach ($times as $time) {
            $time = trim($time);
            if (!empty($time) && mb_strlen($time) <= 10) {
                if (!isset($mealTimes[$time])) {
                    $mealTimes[$time] = 0;
                }
                $mealTimes[$time]++;
            }
        }
    }
    
    arsort($mealTimes);
    
    $list = array();
    $id = 1;
    foreach ($mealTimes as $name => $count) {
        if ($id > $limit) break;
        $list[] = array(
            'id' => $id++,
            'name' => $name,
            'count' => $count
        );
    }
    
    return $list;
}