package controller

import (
	"encoding/json"
	"fmt"
	"io"
	"net/http"
	"strings"

	"github.com/go-chi/chi"
	httputil "github.com/goodrain/rainbond/util/http"
	"github.com/sirupsen/logrus"
)

// KubeBlocksController -
type KubeBlocksController struct{}

// blockMechanicaBaseURL base URL for block-mechanica service
const blockMechanicaBaseURL = "http://kb-adapter-rbdplugin.rbd-system.svc:80"

// GetSupportedDatabases get KubeBlocks supported databases list
func (c *KubeBlocksController) GetSupportedDatabases(w http.ResponseWriter, r *http.Request) {
	c.forwardRequest(w, r, "/v1/addons", "GET")
}

// GetStorageClasses get KubeBlocks storage classes list
func (c *KubeBlocksController) GetStorageClasses(w http.ResponseWriter, r *http.Request) {
	c.forwardRequest(w, r, "/v1/storageclasses", "GET")
}

// GetBackupRepos get KubeBlocks backup repositories list
func (c *KubeBlocksController) GetBackupRepos(w http.ResponseWriter, r *http.Request) {
	c.forwardRequest(w, r, "/v1/backuprepos", "GET")
}

// CreateCluster create KubeBlocks database cluster
func (c *KubeBlocksController) CreateCluster(w http.ResponseWriter, r *http.Request) {
	c.forwardRequest(w, r, "/v1/clusters", "POST")
}

// GetClusterConnectInfos get KubeBlocks clusters connection infos
func (c *KubeBlocksController) GetClusterConnectInfos(w http.ResponseWriter, r *http.Request) {
	c.forwardRequest(w, r, "/v1/clusters/connect-infos", "GET")
}

// GetClusterByID get KubeBlocks cluster by service ID
func (c *KubeBlocksController) GetClusterByID(w http.ResponseWriter, r *http.Request) {
	serviceID := chi.URLParam(r, "service_id")
	c.forwardRequest(w, r, fmt.Sprintf("/v1/clusters/%s", serviceID), "GET")
}

// ExpansionCluster update KubeBlocks cluster
func (c *KubeBlocksController) ExpansionCluster(w http.ResponseWriter, r *http.Request) {
	serviceID := chi.URLParam(r, "service_id")
	c.forwardRequest(w, r, fmt.Sprintf("/v1/clusters/%s", serviceID), "PUT")
}

// UpdateClusterBackupSchedules update KubeBlocks cluster backup schedules
func (c *KubeBlocksController) UpdateClusterBackupSchedules(w http.ResponseWriter, r *http.Request) {
	serviceID := chi.URLParam(r, "service_id")
	c.forwardRequest(w, r, fmt.Sprintf("/v1/clusters/%s/backup-schedules", serviceID), "PUT")
}

// CreateClusterBackup create KubeBlocks cluster backup
func (c *KubeBlocksController) CreateClusterBackup(w http.ResponseWriter, r *http.Request) {
	serviceID := chi.URLParam(r, "service_id")
	c.forwardRequest(w, r, fmt.Sprintf("/v1/clusters/%s/backups", serviceID), "POST")
}

// GetClusterBackups get KubeBlocks cluster backups
func (c *KubeBlocksController) GetClusterBackups(w http.ResponseWriter, r *http.Request) {
	serviceID := chi.URLParam(r, "service_id")
	c.forwardRequest(w, r, fmt.Sprintf("/v1/clusters/%s/backups", serviceID), "GET")
}

// DeleteClusters delete KubeBlocks clusters
func (c *KubeBlocksController) DeleteClusters(w http.ResponseWriter, r *http.Request) {
	c.forwardRequest(w, r, "/v1/clusters", "DELETE")
}

// DeleteClusterBackup delete KubeBlocks cluster backup
func (c *KubeBlocksController) DeleteClusterBackup(w http.ResponseWriter, r *http.Request) {
	serviceID := chi.URLParam(r, "service_id")
	c.forwardRequest(w, r, fmt.Sprintf("/v1/clusters/%s/backups", serviceID), "DELETE")
}

// ManageCluster forwards to block-mechanica to manage cluster lifecycle
func (c *KubeBlocksController) ManageCluster(w http.ResponseWriter, r *http.Request) {
	logrus.Infof("ManageCluster request: %v", r.Body)
	c.forwardRequest(w, r, "/v1/clusters/actions", "POST")
}

// GetClusterPodDetail forwards to block-mechanica to get pod details managed by Cluster
func (c *KubeBlocksController) GetClusterPodDetail(w http.ResponseWriter, r *http.Request) {
	serviceID := chi.URLParam(r, "service_id")
	podName := chi.URLParam(r, "pod_name")
	c.forwardRequest(w, r, fmt.Sprintf("/v1/clusters/%s/pods/%s/details", serviceID, podName), "GET")
}

// GetClusterEvents forwards to block-mechanica to get cluster's events
func (c *KubeBlocksController) GetClusterEvents(w http.ResponseWriter, r *http.Request) {
	serviceID := chi.URLParam(r, "service_id")
	c.forwardRequest(w, r, fmt.Sprintf("/v1/clusters/%s/events", serviceID), "GET")
}

func (c *KubeBlocksController) GetClusterParameters(w http.ResponseWriter, r *http.Request) {
	serviceID := chi.URLParam(r, "service_id")
	c.forwardRequest(w, r, fmt.Sprintf("/v1/clusters/%s/parameters", serviceID), "GET")
}

func (c *KubeBlocksController) ChangeClusterParameters(w http.ResponseWriter, r *http.Request) {
	serviceID := chi.URLParam(r, "service_id")
	c.forwardRequest(w, r, fmt.Sprintf("/v1/clusters/%s/parameters", serviceID), "POST")
}

func (c *KubeBlocksController) RestoreClusterFromBackup(w http.ResponseWriter, r *http.Request) {
	serviceID := chi.URLParam(r, "service_id")
	c.forwardRequest(w, r, fmt.Sprintf("/v1/clusters/%s/restores", serviceID), "POST") // TODO
}

// forwardRequest helper function to forward requests to Block Mechanica
func (c *KubeBlocksController) forwardRequest(w http.ResponseWriter, r *http.Request, api, method string) {
	// 构建URL
	targetURL := blockMechanicaBaseURL + api
	if r.URL.RawQuery != "" {
		targetURL += "?" + r.URL.RawQuery
	}
	logrus.Debugf("request block-mechanica service: %s %s", method, targetURL)

	var req *http.Request
	var err error

	// 读取请求体
	var body io.Reader
	requestBody, readErr := io.ReadAll(r.Body)
	if readErr != nil {
		logrus.Errorf("read request body failed: %v", readErr)
		httputil.ReturnError(r, w, 400, "read request body failed: "+readErr.Error())
		return
	}
	if len(requestBody) > 0 {
		body = strings.NewReader(string(requestBody))
	}
	req, err = http.NewRequest(method, targetURL, body)

	if err != nil {
		logrus.Errorf("create request to block-mechanica failed: %v", err)
		httputil.ReturnError(r, w, 500, "create request to block-mechanica failed: "+err.Error())
		return
	}

	// Set headers
	for key, values := range r.Header {
		for _, value := range values {
			req.Header.Set(key, value)
		}
	}

	if req.Header.Get("Content-Type") == "" && (method == "POST" || method == "PUT" || method == "DELETE") {
		req.Header.Set("Content-Type", "application/json")
	}

	client := &http.Client{}
	resp, err := client.Do(req)
	if err != nil {
		logrus.Errorf("request block-mechanica service failed: %v", err)
		httputil.ReturnError(r, w, 500, "request block-mechanica service failed: "+err.Error())
		return
	}
	defer resp.Body.Close()

	if resp.StatusCode != http.StatusOK {
		body, _ := io.ReadAll(resp.Body)
		logrus.Errorf("block-mechanica service returned error status code %d: %s", resp.StatusCode, string(body))
		httputil.ReturnError(r, w, resp.StatusCode, "block-mechanica service returned error: "+string(body))
		return
	}

	var result map[string]interface{}
	if err := json.NewDecoder(resp.Body).Decode(&result); err != nil {
		logrus.Errorf("parse block-mechanica response failed: %v", err)
		httputil.ReturnError(r, w, 500, "parse block-mechanica response failed: "+err.Error())
		return
	}

	if list, exists := result["list"]; exists {
		// 尝试提取分页信息，存在分页信息则 ReturnList
		if total, pageNum, ok := extractPaginationInfo(result); ok {
			httputil.ReturnList(r, w, total, pageNum, list)
			return
		}

		httputil.ReturnSuccess(r, w, list)
	} else if field, exists := result["bean"]; exists {
		httputil.ReturnSuccess(r, w, field)
	} else {
		httputil.ReturnSuccess(r, w, result)
	}
}

// extractPaginationInfo 从结果中提取分页信息
func extractPaginationInfo(result map[string]interface{}) (total, pageNum int, ok bool) {
	number, hasNumber := result["number"]
	if !hasNumber {
		return 0, 0, false
	}

	page, hasPage := result["page"]
	if !hasPage {
		return 0, 0, false
	}

	total, totalOk := safeToInt(number)
	if !totalOk {
		return 0, 0, false
	}

	pageNum, pageOk := safeToInt(page)
	if !pageOk {
		return 0, 0, false
	}

	return total, pageNum, true
}

// safeToInt 安全地将 interface{} 转换为 int，支持多种数字类型
func safeToInt(value interface{}) (int, bool) {
	switch v := value.(type) {
	case int:
		return v, true
	case int32:
		return int(v), true
	case int64:
		return int(v), true
	case float32:
		return int(v), true
	case float64:
		return int(v), true
	case json.Number:
		if i, err := v.Int64(); err == nil {
			return int(i), true
		}
	}
	logrus.Warnf("Failed to convert %T(%v) to int", value, value)
	return 0, false
}