package controller

import (
	"fmt"
	"sort"
	"strconv"
	"time"

	"ezops/model"

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

func (h *KubernetesHandler) ListEvents(c *gin.Context) {
	clusterID := h.resolveClusterCode(c.Param("clusterCode"))
	if clusterID == 0 { c.JSON(500, model.Response{Code: 500, Message: "cluster not found"}); return }
	client, _, err := h.getK8sClient(clusterID)
	if err != nil { c.JSON(500, model.Response{Code: 500, Message: err.Error()}); return }

	ns := c.Query("namespace")
	eventType := c.Query("type") // Normal or Warning
	events, err := client.ListEvents(ns)
	if err != nil { c.JSON(500, model.Response{Code: 500, Message: "K8s API error: " + err.Error()}); return }

	type EventSummary struct {
		Namespace string `json:"namespace"`
		Name      string `json:"name"`
		Type      string `json:"type"`
		Reason    string `json:"reason"`
		Message   string `json:"message"`
		Object    string `json:"object"`
		Count     int    `json:"count"`
		FirstTime string `json:"first_time"`
		LastTime  string `json:"last_time"`
	}
	result := []EventSummary{}
	for _, e := range events.Items {
		if eventType != "" && e.Type != eventType { continue }
		object := fmt.Sprintf("%s/%s", e.InvolvedObject.Kind, e.InvolvedObject.Name)
		if e.InvolvedObject.Namespace != "" {
			object = fmt.Sprintf("%s/%s/%s", e.InvolvedObject.Namespace, e.InvolvedObject.Kind, e.InvolvedObject.Name)
		}
		firstTime := ""; if !e.FirstTimestamp.IsZero() { firstTime = e.FirstTimestamp.Format(time.RFC3339) }
		lastTime := ""; if !e.LastTimestamp.IsZero() { lastTime = e.LastTimestamp.Format(time.RFC3339) }
		result = append(result, EventSummary{
			Namespace: e.Metadata.Namespace, Name: e.Metadata.Name, Type: e.Type, Reason: e.Reason,
			Message: e.Message, Object: object, Count: int(e.Count),
			FirstTime: firstTime, LastTime: lastTime,
		})
	}
	c.JSON(200, model.Response{Code: 200, Data: result})
}

// ============================================================================
// Event Aggregation — 事件聚合统计 (M12)
// ============================================================================

// GetEventsSummary returns aggregated event statistics for dashboard
func (h *KubernetesHandler) GetEventsSummary(c *gin.Context) {
	clusterID := h.resolveClusterCode(c.Param("clusterCode"))
	if clusterID == 0 {
		c.JSON(500, model.Response{Code: 500, Message: "cluster not found"})
		return
	}
	client, _, err := h.getK8sClient(clusterID)
	if err != nil {
		c.JSON(500, model.Response{Code: 500, Message: err.Error()})
		return
	}

	ns := c.Query("namespace")
	events, err := client.ListEvents(ns)
	if err != nil {
		c.JSON(500, model.Response{Code: 500, Message: "K8s API error: " + err.Error()})
		return
	}

	// Time window filter (hours)
	timeWindowHours := 0
	if tw := c.Query("hours"); tw != "" {
		if v, err := strconv.Atoi(tw); err == nil && v > 0 {
			timeWindowHours = v
		}
	}
	now := time.Now()
	cutoff := time.Time{}
	if timeWindowHours > 0 {
		cutoff = now.Add(-time.Duration(timeWindowHours) * time.Hour)
	}

	// Aggregation maps
	totalCount := 0
	warningCount := 0
	normalCount := 0
	byReason := map[string]int{}
	byNamespace := map[string]int{}
	byKind := map[string]int{}
	recentWarnings := []map[string]interface{}{}

	for _, e := range events.Items {
		// Time window filter
		if !cutoff.IsZero() && !e.LastTimestamp.IsZero() && e.LastTimestamp.Before(cutoff) {
			continue
		}

		totalCount++
		count := int(e.Count)
		if count == 0 {
			count = 1
		}

		nsName := e.Metadata.Namespace
		if nsName == "" {
			nsName = e.InvolvedObject.Namespace
		}

		if e.Type == "Warning" {
			warningCount += count
			byReason[e.Reason] += count
			byNamespace[nsName] += count
			byKind[e.InvolvedObject.Kind] += count

			// Collect recent warning events (top 10 by lastTimestamp)
			if len(recentWarnings) < 50 {
				recentWarnings = append(recentWarnings, map[string]interface{}{
					"namespace":  nsName,
					"type":       e.Type,
					"reason":     e.Reason,
					"message":    e.Message,
					"object":     fmt.Sprintf("%s/%s", e.InvolvedObject.Kind, e.InvolvedObject.Name),
					"count":      count,
					"last_time":  e.LastTimestamp.Format(time.RFC3339),
					"first_time": e.FirstTimestamp.Format(time.RFC3339),
				})
			}
		} else {
			normalCount += count
		}
	}

	// Sort byReason by count desc → top reasons
	type ReasonStat struct {
		Reason string `json:"reason"`
		Count  int    `json:"count"`
	}
	reasonList := make([]ReasonStat, 0, len(byReason))
	for r, cnt := range byReason {
		reasonList = append(reasonList, ReasonStat{Reason: r, Count: cnt})
	}
	sort.Slice(reasonList, func(i, j int) bool { return reasonList[i].Count > reasonList[j].Count })
	if len(reasonList) > 15 {
		reasonList = reasonList[:15]
	}

	// Sort byNamespace
	type NsStat struct {
		Namespace string `json:"namespace"`
		Count     int    `json:"count"`
	}
	nsList := make([]NsStat, 0, len(byNamespace))
	for n, cnt := range byNamespace {
		nsList = append(nsList, NsStat{Namespace: n, Count: cnt})
	}
	sort.Slice(nsList, func(i, j int) bool { return nsList[i].Count > nsList[j].Count })
	if len(nsList) > 15 {
		nsList = nsList[:15]
	}

	// Sort byKind
	type KindStat struct {
		Kind  string `json:"kind"`
		Count int    `json:"count"`
	}
	kindList := make([]KindStat, 0, len(byKind))
	for k, cnt := range byKind {
		kindList = append(kindList, KindStat{Kind: k, Count: cnt})
	}
	sort.Slice(kindList, func(i, j int) bool { return kindList[i].Count > kindList[j].Count })

	// Sort recentWarnings by last_time desc
	sort.Slice(recentWarnings, func(i, j int) bool {
		ti, _ := recentWarnings[i]["last_time"].(string)
		tj, _ := recentWarnings[j]["last_time"].(string)
		return ti > tj
	})
	if len(recentWarnings) > 10 {
		recentWarnings = recentWarnings[:10]
	}

	result := map[string]interface{}{
		"total":           totalCount,
		"warning_count":   warningCount,
		"normal_count":    normalCount,
		"by_reason":       reasonList,
		"by_namespace":    nsList,
		"by_kind":         kindList,
		"recent_warnings": recentWarnings,
	}

	c.JSON(200, model.Response{Code: 200, Data: result})
}

// ============================================================================
// Capacity Analysis — CPU/Memory request/limit per Deployment
// ============================================================================

// GetCapacityAnalysis returns resource analysis for all deployments