package logic

import (
	"context"
	"strconv"
	"strings"
	"time"

	"github.com/gogf/gf/v2/frame/g"

	"easygoadmin/api/v1"
	"easygoadmin/internal/service"
	"easygoadmin/utility/cache"
)

// ============================== 缓存监控业务实现 ==============================

// sCacheMonitor 缓存监控业务实现
// Redis 模式解析 INFO 各节；内存降级模式仅返回模式标识
type sCacheMonitor struct{}

func init() {
	service.RegisterCacheMonitor(&sCacheMonitor{})
}

// Info 查询缓存监控信息
func (s *sCacheMonitor) Info(ctx context.Context, req *v1.CacheInfoReq) (res *v1.CacheInfoRes, err error) {
	if cache.UsingMemory() {
		return &v1.CacheInfoRes{Mode: "memory", Connected: false}, nil
	}
	res = &v1.CacheInfoRes{Mode: "redis", Connected: true}
	sections := map[string]map[string]string{}
	for _, name := range []string{"server", "memory", "stats", "clients", "keyspace"} {
		v, err := g.Redis().Do(ctx, "INFO", name)
		if err != nil {
			res.Connected = false
			return res, nil
		}
		sections[name] = parseRedisInfo(v.String())
	}

	res.Version = sections["server"]["redis_version"]
	if sec, e := strconv.ParseInt(sections["server"]["uptime_in_seconds"], 10, 64); e == nil {
		res.Uptime = (time.Duration(sec) * time.Second).String()
	}
	res.UsedMemory = sections["memory"]["used_memory_human"]
	res.UsedMemoryPeak = sections["memory"]["used_memory_peak_human"]
	res.MaxMemory = sections["memory"]["maxmemory_human"]
	res.FragRatio = sections["memory"]["mem_fragmentation_ratio"]
	res.ConnectedClients, _ = strconv.ParseInt(sections["clients"]["connected_clients"], 10, 64)
	res.ExpiredKeys, _ = strconv.ParseInt(sections["stats"]["expired_keys"], 10, 64)
	res.EvictedKeys, _ = strconv.ParseInt(sections["stats"]["evicted_keys"], 10, 64)
	res.TotalCommands, _ = strconv.ParseInt(sections["stats"]["total_commands_processed"], 10, 64)
	res.TotalConns, _ = strconv.ParseInt(sections["stats"]["total_connections_received"], 10, 64)
	res.Hits, _ = strconv.ParseInt(sections["stats"]["keyspace_hits"], 10, 64)
	res.Misses, _ = strconv.ParseInt(sections["stats"]["keyspace_misses"], 10, 64)
	if total := res.Hits + res.Misses; total > 0 {
		res.HitRate = strconv.FormatFloat(float64(res.Hits)/float64(total)*100, 'f', 2, 64)
	} else {
		res.HitRate = "0.00"
	}
	if v, e := g.Redis().Do(ctx, "DBSIZE"); e == nil {
		res.Keys = v.Int64()
	}
	for k, line := range sections["keyspace"] {
		if !strings.HasPrefix(k, "db") {
			continue
		}
		entry := v1.CacheKeySpaceDb{Db: k}
		for _, kv := range strings.Split(line, ",") {
			parts := strings.SplitN(kv, "=", 2)
			if len(parts) != 2 {
				continue
			}
			switch parts[0] {
			case "keys":
				entry.Keys, _ = strconv.ParseInt(parts[1], 10, 64)
			case "expires":
				entry.Expires, _ = strconv.ParseInt(parts[1], 10, 64)
			}
		}
		res.KeySpace = append(res.KeySpace, entry)
	}
	return res, nil
}

// parseRedisInfo 解析 INFO 输出为 键→值 映射
func parseRedisInfo(s string) map[string]string {
	out := map[string]string{}
	for _, line := range strings.Split(s, "\n") {
		line = strings.TrimSpace(line)
		if line == "" || strings.HasPrefix(line, "#") {
			continue
		}
		if idx := strings.Index(line, ":"); idx > 0 {
			out[line[:idx]] = strings.TrimSpace(line[idx+1:])
		}
	}
	return out
}