package com.xuqm.update.service;

import com.xuqm.update.repository.DeviceRecordRepository;
import org.springframework.stereotype.Service;

import java.time.LocalDateTime;
import java.util.ArrayList;
import java.util.LinkedHashMap;
import java.util.List;
import java.util.Map;

@Service
public class UpdateStatisticsService {

    private final DeviceRecordRepository deviceRecordRepository;

    public UpdateStatisticsService(DeviceRecordRepository deviceRecordRepository) {
        this.deviceRecordRepository = deviceRecordRepository;
    }

    /**
     * 版本分布：各版本的设备数占比
     * 返回 [{ versionCode, versionName, deviceCount }]
     */
    public List<Map<String, Object>> getVersionDistribution(String appKey, String platform, int days) {
        LocalDateTime since = LocalDateTime.now().minusDays(days);
        List<Object[]> rows = deviceRecordRepository.findVersionDistribution(appKey, platform, since);
        List<Map<String, Object>> result = new ArrayList<>();
        for (Object[] row : rows) {
            Map<String, Object> item = new LinkedHashMap<>();
            item.put("versionCode", row[0]);
            item.put("versionName", row[1]);
            item.put("deviceCount", row[2]);
            result.add(item);
        }
        return result;
    }

    /**
     * 设备型号分布 Top N
     * 返回 [{ model, deviceCount }]
     */
    public List<Map<String, Object>> getDeviceDistribution(String appKey, String platform, int days) {
        LocalDateTime since = LocalDateTime.now().minusDays(days);
        List<Object[]> models = deviceRecordRepository.findModelDistribution(appKey, platform, since, 10);
        List<Map<String, Object>> result = new ArrayList<>();
        for (Object[] row : models) {
            Map<String, Object> item = new LinkedHashMap<>();
            item.put("model", row[0]);
            item.put("deviceCount", row[1]);
            result.add(item);
        }
        return result;
    }

    /**
     * 系统版本分布
     * 返回 [{ osVersion, deviceCount }]
     */
    public List<Map<String, Object>> getOsVersionDistribution(String appKey, String platform, int days) {
        LocalDateTime since = LocalDateTime.now().minusDays(days);
        List<Object[]> rows = deviceRecordRepository.findOsVersionDistribution(appKey, platform, since, 10);
        List<Map<String, Object>> result = new ArrayList<>();
        for (Object[] row : rows) {
            Map<String, Object> item = new LinkedHashMap<>();
            item.put("osVersion", row[0]);
            item.put("deviceCount", row[1]);
            result.add(item);
        }
        return result;
    }

    /**
     * 厂商分布
     * 返回 [{ vendor, deviceCount }]
     */
    public List<Map<String, Object>> getVendorDistribution(String appKey, String platform, int days) {
        LocalDateTime since = LocalDateTime.now().minusDays(days);
        List<Object[]> rows = deviceRecordRepository.findVendorDistribution(appKey, platform, since);
        List<Map<String, Object>> result = new ArrayList<>();
        for (Object[] row : rows) {
            Map<String, Object> item = new LinkedHashMap<>();
            item.put("vendor", row[0]);
            item.put("deviceCount", row[1]);
            result.add(item);
        }
        return result;
    }

    /**
     * 每日检测趋势
     * 返回 [{ day, deviceCount }]
     */
    public List<Map<String, Object>> getDailyTrend(String appKey, String platform, int days) {
        LocalDateTime since = LocalDateTime.now().minusDays(days);
        List<Object[]> rows = deviceRecordRepository.findDailyTrend(appKey, platform, since);
        List<Map<String, Object>> result = new ArrayList<>();
        for (Object[] row : rows) {
            Map<String, Object> item = new LinkedHashMap<>();
            item.put("day", row[0] != null ? row[0].toString() : "");
            item.put("deviceCount", row[1]);
            result.add(item);
        }
        return result;
    }
}