package handlers

import (
	"encoding/json"
	"fmt"
	"net/http"
	"time"

	"ezops/internal/models"

	"github.com/gin-gonic/gin"
	"gorm.io/gorm"
)

// AgentHandler 处理 Agent 上报数据 // Logan.Li
type AgentHandler struct {
	db *gorm.DB
}

func NewAgentHandler(db *gorm.DB) *AgentHandler {
	return &AgentHandler{db: db}
}

// ReceiveReport 接收 Agent 上报的指标数据
// POST /api/v1/agent/report
func (h *AgentHandler) ReceiveReport(c *gin.Context) {
	var req models.AgentReportRequest
	if err := c.ShouldBindJSON(&req); err != nil {
		c.JSON(http.StatusBadRequest, models.Response{Code: 400, Message: "请求格式错误: " + err.Error()})
		return
	}

	// 解析上报时间
	reportTime := time.Now()
	if req.Timestamp != "" {
		if t, err := time.Parse(time.RFC3339, req.Timestamp); err == nil {
			reportTime = t
		}
	}

	// 序列化磁盘和端口信息
	diskJSON, _ := json.Marshal(req.Disks)
	portJSON, _ := json.Marshal(req.Ports)

	// 存储到数据库
	report := models.AgentReport{
		Hostname:   req.Hostname,
		CPUUsage:   req.CPU.UsagePercent,
		CPUCores:   req.CPU.CoreCount,
		Load1:      req.CPU.Load1,
		Load5:      req.CPU.Load5,
		Load15:     req.CPU.Load15,
		MemTotal:   req.Memory.TotalGB,
		MemUsed:    req.Memory.UsedGB,
		MemUsage:   req.Memory.UsagePercent,
		DiskInfo:   string(diskJSON),
		PortInfo:   string(portJSON),
		ReportTime: reportTime,
	}

	if err := h.db.Create(&report).Error; err != nil {
		c.JSON(http.StatusInternalServerError, models.Response{Code: 500, Message: "保存失败: " + err.Error()})
		return
	}

	// 保存成功
	c.JSON(http.StatusOK, models.Response{Code: 200, Message: "ok"})
}

// GetLatestReports 获取各主机最新上报
// GET /api/v1/agent/latest
func (h *AgentHandler) GetLatestReports(c *gin.Context) {
	// 子查询：每个 hostname 最新的一条记录
	var reports []models.AgentReport
	h.db.Raw(`
		SELECT * FROM agent_reports 
		WHERE id IN (
			SELECT MAX(id) FROM agent_reports GROUP BY hostname
		)
		ORDER BY report_time DESC
	`).Scan(&reports)

	c.JSON(http.StatusOK, models.Response{
		Code:    200,
		Message: "success",
		Data:    reports,
	})
}

// GetHostHistory 获取指定主机的历史指标
// GET /api/v1/agent/history/:hostname?hours=1
func (h *AgentHandler) GetHostHistory(c *gin.Context) {
	hostname := c.Param("hostname")
	hours := 1
	if v := c.Query("hours"); v != "" {
		fmt.Sscanf(v, "%d", &hours)
	}
	since := time.Now().Add(-time.Duration(hours) * time.Hour)

	var reports []models.AgentReport
	h.db.Where("hostname = ? AND report_time >= ?", hostname, since).
		Order("report_time ASC").
		Find(&reports)

	c.JSON(http.StatusOK, models.Response{
		Code:    200,
		Message: "success",
		Data:    reports,
	})
}