// Copyright 2022-2023 EMQ Technologies Co., Ltd.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

package server

import (
	"context"
	"errors"
	"fmt"
	"github.com/lf-edge/ekuiper/internal/binder/function"
	"github.com/lf-edge/ekuiper/internal/binder/io"
	"github.com/lf-edge/ekuiper/internal/binder/meta"
	"github.com/lf-edge/ekuiper/internal/conf"
	meta2 "github.com/lf-edge/ekuiper/internal/meta"
	"github.com/lf-edge/ekuiper/internal/pkg/store"
	"github.com/lf-edge/ekuiper/internal/processor"
	"github.com/lf-edge/ekuiper/internal/topo/connection/factory"
	"github.com/lf-edge/ekuiper/internal/topo/rule"
	"github.com/lf-edge/ekuiper/pkg/ast"
	"net/http"
	"os"
	"os/signal"
	"path/filepath"
	"sort"
	"syscall"
	"time"
)

var (
	logger           = conf.Log
	startTimeStamp   int64
	version          = ""
	ruleProcessor    *processor.RuleProcessor
	streamProcessor  *processor.StreamProcessor
	rulesetProcessor *processor.RulesetProcessor
)

// Create path if mount an empty dir. For edgeX, all the folders must be created priorly
func createPaths() {
	dataDir, err := conf.GetDataLoc()
	if err != nil {
		panic(err)
	}
	dirs := []string{"uploads", "sources", "sinks", "functions", "services", "services/schemas", "connections"}

	for _, v := range dirs {
		// Create dir if not exist
		realDir := filepath.Join(dataDir, v)
		if _, err := os.Stat(realDir); os.IsNotExist(err) {
			if err := os.MkdirAll(realDir, os.ModePerm); err != nil {
				fmt.Printf("Failed to create dir %s: %v", realDir, err)
			}
		}
	}

	files := []string{"connections/connection.yaml"}
	for _, v := range files {
		// Create dir if not exist
		realFile := filepath.Join(dataDir, v)
		if _, err := os.Stat(realFile); os.IsNotExist(err) {
			if _, err := os.Create(realFile); err != nil {
				fmt.Printf("Failed to create file %s: %v", realFile, err)
			}
		}
	}

}

func StartUp(Version, LoadFileType string) {
	version = Version
	conf.LoadFileType = LoadFileType
	startTimeStamp = time.Now().Unix()
	createPaths()
	conf.InitConf()
	factory.InitClientsFactory()

	err := store.SetupWithKuiperConfig(conf.Config)
	if err != nil {
		panic(err)
	}

	meta2.InitYamlConfigManager()
	ruleProcessor = processor.NewRuleProcessor()
	streamProcessor = processor.NewStreamProcessor()
	rulesetProcessor = processor.NewRulesetProcessor(ruleProcessor, streamProcessor)

	// register all extensions
	for k, v := range components {
		logger.Infof("register component %s", k)
		v.register()
	}

	// Bind the source, function, sink
	sort.Sort(entries)
	err = function.Initialize(entries)
	if err != nil {
		panic(err)
	}
	err = io.Initialize(entries)
	if err != nil {
		panic(err)
	}
	meta.Bind()
	initRuleset()

	registry = &RuleRegistry{internal: make(map[string]*rule.RuleState)}
	//Start lookup tables
	streamProcessor.RecoverLookupTable()
	//Start rules
	if rules, err := ruleProcessor.GetAllRules(); err != nil {
		logger.Infof("Start rules error: %s", err)
	} else {
		logger.Info("Starting rules")
		var reply string
		for _, name := range rules {
			rule, err := ruleProcessor.GetRuleById(name)
			if err != nil {
				logger.Error(err)
				continue
			}
			//err = server.StartRule(rule, &reply)
			reply = recoverRule(rule)
			if 0 != len(reply) {
				logger.Info(reply)
			}
		}
	}

	//Start rest service
	srvRest := createRestServer(conf.Config.Basic.RestIp, conf.Config.Basic.RestPort, conf.Config.Basic.Authentication)
	go func() {
		var err error
		if conf.Config.Basic.RestTls == nil {
			err = srvRest.ListenAndServe()
		} else {
			err = srvRest.ListenAndServeTLS(conf.Config.Basic.RestTls.Certfile, conf.Config.Basic.RestTls.Keyfile)
		}
		if err != nil && err != http.ErrServerClosed {
			logger.Errorf("Error serving rest service: %s", err)
		}
	}()

	// Start extend services
	for k, v := range servers {
		logger.Infof("start service %s", k)
		v.serve()
	}

	//Startup message
	restHttpType := "http"
	if conf.Config.Basic.RestTls != nil {
		restHttpType = "https"
	}
	msg := fmt.Sprintf("Serving kuiper (version - %s) on port %d, and restful api on %s://%s:%d. \n", Version, conf.Config.Basic.Port, restHttpType, conf.Config.Basic.RestIp, conf.Config.Basic.RestPort)
	logger.Info(msg)
	fmt.Printf(msg)

	//Stop the services
	sigint := make(chan os.Signal, 1)
	signal.Notify(sigint, os.Interrupt, syscall.SIGTERM)
	<-sigint

	if err = srvRest.Shutdown(context.TODO()); err != nil {
		logger.Errorf("rest server shutdown error: %v", err)
	}
	logger.Info("rest server successfully shutdown.")

	// close extend services
	for k, v := range servers {
		logger.Infof("close service %s", k)
		v.close()
	}

	os.Exit(0)
}

func initRuleset() error {
	loc, err := conf.GetDataLoc()
	if err != nil {
		return err
	}
	signalFile := filepath.Join(loc, "initialized")
	if _, err := os.Stat(signalFile); errors.Is(err, os.ErrNotExist) {
		defer os.Create(signalFile)
		content, err := os.ReadFile(filepath.Join(loc, "init.json"))
		if err != nil {
			conf.Log.Infof("fail to read init file: %v", err)
			return nil
		}
		conf.Log.Infof("start to initialize ruleset")
		_, counts, err := rulesetProcessor.Import(content)
		conf.Log.Infof("initialzie %d streams, %d tables and %d rules", counts[0], counts[1], counts[2])
	}
	return nil
}

func resetAllRules() error {
	rules, err := ruleProcessor.GetAllRules()
	if err != nil {
		return err
	}
	for _, name := range rules {
		_ = deleteRule(name)
		_, err := ruleProcessor.ExecDrop(name)
		if err != nil {
			logger.Warnf("delete rule: %s with error %v", name, err)
			continue
		}
	}
	return nil
}

func resetAllStreams() error {
	allStreams, err := streamProcessor.GetAll()
	if err != nil {
		return err
	}
	Streams := allStreams["streams"]
	Tables := allStreams["tables"]

	for name, _ := range Streams {
		_, err2 := streamProcessor.DropStream(name, ast.TypeStream)
		if err2 != nil {
			logger.Warnf("streamProcessor DropStream %s error: %v", name, err2)
			continue
		}
	}
	for name, _ := range Tables {
		_, err2 := streamProcessor.DropStream(name, ast.TypeTable)
		if err2 != nil {
			logger.Warnf("streamProcessor DropTable %s error: %v", name, err2)
			continue
		}
	}
	return nil
}