package metrics

import (
	"fmt"
	"sync"

	"github.com/gin-gonic/gin"
	"github.com/prometheus/client_golang/prometheus"
	"github.com/prometheus/client_golang/prometheus/promauto"
	"github.com/prometheus/client_golang/prometheus/promhttp"
)

type Key struct {
	Group   string
	Version string
	Kind    string
}

func init() {
	gin.SetMode(gin.ReleaseMode)
	gin.DisableConsoleColor()
}

var Mutex sync.Mutex
var (
	// Variables that are to be registered with prometheus.
	// promauto automactically registers the variable with prometheus. If promauto is not used variable needs to be registered using prometheus.register
	// The following variables are of type Gauge metric.
	CtlfishResourceCreations = promauto.NewCounterVec(
		prometheus.CounterOpts{
			Namespace: "ctlfish",
			Name:      "resource_creations",
			Help:      "Resources Created by ctlfish",
		}, []string{"Group", "Version", "Kind"})

	CtlfishResourceUpdates = promauto.NewCounterVec(
		prometheus.CounterOpts{
			Namespace: "ctlfish",
			Name:      "resource_updates",
			Help:      "Resources Updated by ctlfish",
		}, []string{"Group", "Version", "Kind"})

	CtlfishResourceDeletions = promauto.NewCounterVec(
		prometheus.CounterOpts{
			Namespace: "ctlfish",
			Name:      "resource_deletions",
			Help:      "Resources Deleted by ctlfish",
		}, []string{"Group", "Version", "Kind"})
)

type ServerConfig struct {
	Port int
}

type LogMessageObject struct {
	Level     string `json:"level"` // "info", "warn", "error"
	Timestamp int64  `json:"ts"`    // When the request is received
	Msg       string `json:"msg"`   // The log message

	// Request info
	RequestBody []byte // base64 encoded in logs for better parsing/safety.
	UserAgent   string
	RemoteAddr  string
	Method      string
	URL         string

	// Response info
	Status  int
	Latency string // How long the request took to process.
}

type Server struct {
	Router *gin.Engine

	Config ServerConfig
}

var MetricsEndpoints = []string{"/metrics", "/ctlfish/metrics"}

// NewServer creates a Ctlfish server that runs on the desired port.
func NewServer(cfg ServerConfig) (*Server, error) {
	if cfg.Port <= 0 || cfg.Port > 65535 {
		return nil, fmt.Errorf("Invalid port number %q", cfg.Port)
	}

	s := &Server{
		Config: cfg,
	}

	// setup router
	s.Router = gin.New()

	// metrics (prometheus) endpoints
	metricsHandlerFunc := gin.WrapH(promhttp.Handler())
	for _, mep := range MetricsEndpoints {
		s.Router.GET(mep, metricsHandlerFunc)
	}

	return s, nil
}

// Run runs the Gin server on the configured port
func (s *Server) Run() {
	addr := fmt.Sprintf(":%d", s.Config.Port)
	err := s.Router.Run(addr)
	if err != nil {
		fmt.Print("Error when Running the router")
	}
}