/*
	Copyright 2021 SANGFOR TECHNOLOGIES

	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 base

import (
	"fmt"
	"gitee.com/opengauss/ham4db/go/core/log"
	"gitee.com/opengauss/ham4db/go/core/system/osp"
	"gitee.com/opengauss/ham4db/go/dtstruct"
	goos "os"
	"strings"
	"time"
)

// executeProcesses executes a list of processes
func ExecuteProcesses(processes []string, description string, topologyRecovery *dtstruct.TopologyRecovery, failOnError bool) (err error) {
	if len(processes) == 0 {
		AuditTopologyRecovery(topologyRecovery, fmt.Sprintf("No %s hooks to run", description))
		return nil
	}

	AuditTopologyRecovery(topologyRecovery, fmt.Sprintf("Running %d %s hooks", len(processes), description))
	for i, command := range processes {
		command, async := prepareCommand(command, topologyRecovery)
		env := applyEnvironmentVariables(topologyRecovery)
		//todo:异步执行
		async = true
		fullDescription := fmt.Sprintf("%s hook %d of %d", description, i+1, len(processes))
		if async {
			fullDescription = fmt.Sprintf("%s (async)", fullDescription)
		}
		if async {
			// Ignore errors
			go ExecuteProcess(command, env, topologyRecovery, fullDescription)
		} else {
			//todo:此处有报错，先异步处理了
			if cmdErr := ExecuteProcess(command, env, topologyRecovery, fullDescription); cmdErr != nil {
				if failOnError {
					AuditTopologyRecovery(topologyRecovery, fmt.Sprintf("Not running further %s hooks", description))
					return cmdErr
				}
				if err == nil {
					// Keep first error encountered
					err = cmdErr
				}
			}
		}
	}
	AuditTopologyRecovery(topologyRecovery, fmt.Sprintf("done running %s hooks", description))
	return err
}

// applyEnvironmentVariables sets the relevant environment variables for a recovery
func applyEnvironmentVariables(topologyRecovery *dtstruct.TopologyRecovery) []string {
	analysisEntry := &topologyRecovery.AnalysisEntry
	env := goos.Environ()
	env = append(env, fmt.Sprintf("ORC_FAILURE_TYPE=%s", string(analysisEntry.Analysis)))
	env = append(env, fmt.Sprintf("ORC_INSTANCE_TYPE=%s", string(analysisEntry.GetAnalysisInstanceType())))
	env = append(env, fmt.Sprintf("ORC_IS_MASTER=%t", analysisEntry.IsMaster))
	env = append(env, fmt.Sprintf("ORC_IS_CO_MASTER=%t", analysisEntry.IsCoMaster))
	env = append(env, fmt.Sprintf("ORC_FAILURE_DESCRIPTION=%s", analysisEntry.Description))
	env = append(env, fmt.Sprintf("ORC_COMMAND=%s", analysisEntry.CommandHint))
	env = append(env, fmt.Sprintf("ORC_FAILED_HOST=%s", analysisEntry.AnalyzedInstanceKey.Hostname))
	env = append(env, fmt.Sprintf("ORC_FAILED_PORT=%d", analysisEntry.AnalyzedInstanceKey.Port))
	env = append(env, fmt.Sprintf("ORC_FAILURE_CLUSTER=%s", analysisEntry.ClusterDetails.ClusterName))
	env = append(env, fmt.Sprintf("ORC_FAILURE_CLUSTER_ALIAS=%s", analysisEntry.ClusterDetails.ClusterAlias))
	env = append(env, fmt.Sprintf("ORC_FAILURE_CLUSTER_DOMAIN=%s", analysisEntry.ClusterDetails.ClusterDomain))
	env = append(env, fmt.Sprintf("ORC_COUNT_REPLICAS=%d", analysisEntry.CountReplicas))
	env = append(env, fmt.Sprintf("ORC_IS_DOWNTIMED=%v", analysisEntry.IsDowntimed))
	env = append(env, fmt.Sprintf("ORC_AUTO_MASTER_RECOVERY=%v", analysisEntry.ClusterDetails.HasAutomatedMasterRecovery))
	env = append(env, fmt.Sprintf("ORC_AUTO_INTERMEDIATE_MASTER_RECOVERY=%v", analysisEntry.ClusterDetails.HasAutomatedIntermediateMasterRecovery))
	env = append(env, fmt.Sprintf("ORC_HAM4DB_HOST=%s", osp.GetHostname()))
	env = append(env, fmt.Sprintf("ORC_IS_SUCCESSFUL=%v", (topologyRecovery.SuccessorKey != nil)))
	env = append(env, fmt.Sprintf("ORC_LOST_REPLICAS=%s", topologyRecovery.LostReplicas.ToCommaDelimitedList()))
	env = append(env, fmt.Sprintf("ORC_REPLICA_HOSTS=%s", analysisEntry.Downstreams.ToCommaDelimitedList()))
	env = append(env, fmt.Sprintf("ORC_RECOVERY_UID=%s", topologyRecovery.UID))

	if topologyRecovery.SuccessorKey != nil {
		env = append(env, fmt.Sprintf("ORC_SUCCESSOR_HOST=%s", topologyRecovery.SuccessorKey.Hostname))
		env = append(env, fmt.Sprintf("ORC_SUCCESSOR_PORT=%d", topologyRecovery.SuccessorKey.Port))
		// As long as SucesssorKey != nil, we replace {successorAlias}.
		// If SucessorAlias is "", it's fine. We'll replace {successorAlias} with "".
		env = append(env, fmt.Sprintf("ORC_SUCCESSOR_ALIAS=%s", topologyRecovery.SuccessorAlias))
	}

	return env
}

// prepareCommand replaces agreed-upon placeholders with analysis data
func prepareCommand(command string, topologyRecovery *dtstruct.TopologyRecovery) (result string, async bool) {
	analysisEntry := &topologyRecovery.AnalysisEntry
	command = strings.TrimSpace(command)
	if strings.HasSuffix(command, "&") {
		command = strings.TrimRight(command, "&")
		async = true
	}
	command = strings.Replace(command, "{failureType}", string(analysisEntry.Analysis), -1)
	command = strings.Replace(command, "{instanceType}", string(analysisEntry.GetAnalysisInstanceType()), -1)
	command = strings.Replace(command, "{isMaster}", fmt.Sprintf("%t", analysisEntry.IsMaster), -1)
	command = strings.Replace(command, "{isCoMaster}", fmt.Sprintf("%t", analysisEntry.IsCoMaster), -1)
	command = strings.Replace(command, "{failureDescription}", analysisEntry.Description, -1)
	command = strings.Replace(command, "{command}", analysisEntry.CommandHint, -1)
	command = strings.Replace(command, "{failedHost}", analysisEntry.AnalyzedInstanceKey.Hostname, -1)
	command = strings.Replace(command, "{failedPort}", fmt.Sprintf("%d", analysisEntry.AnalyzedInstanceKey.Port), -1)
	command = strings.Replace(command, "{failureCluster}", analysisEntry.ClusterDetails.ClusterName, -1)
	command = strings.Replace(command, "{failureClusterAlias}", analysisEntry.ClusterDetails.ClusterAlias, -1)
	command = strings.Replace(command, "{failureClusterDomain}", analysisEntry.ClusterDetails.ClusterDomain, -1)
	command = strings.Replace(command, "{countSlaves}", fmt.Sprintf("%d", analysisEntry.CountReplicas), -1)
	command = strings.Replace(command, "{countReplicas}", fmt.Sprintf("%d", analysisEntry.CountReplicas), -1)
	command = strings.Replace(command, "{isDowntimed}", fmt.Sprint(analysisEntry.IsDowntimed), -1)
	command = strings.Replace(command, "{autoMasterRecovery}", fmt.Sprint(analysisEntry.ClusterDetails.HasAutomatedMasterRecovery), -1)
	command = strings.Replace(command, "{autoIntermediateMasterRecovery}", fmt.Sprint(analysisEntry.ClusterDetails.HasAutomatedIntermediateMasterRecovery), -1)
	command = strings.Replace(command, "{ham4dbHost}", osp.GetHostname(), -1)
	command = strings.Replace(command, "{recoveryUID}", topologyRecovery.UID, -1)

	command = strings.Replace(command, "{isSuccessful}", fmt.Sprint(topologyRecovery.SuccessorKey != nil), -1)
	if topologyRecovery.SuccessorKey != nil {
		command = strings.Replace(command, "{successorHost}", topologyRecovery.SuccessorKey.Hostname, -1)
		command = strings.Replace(command, "{successorPort}", fmt.Sprintf("%d", topologyRecovery.SuccessorKey.Port), -1)
		// As long as SucesssorKey != nil, we replace {successorAlias}.
		// If SucessorAlias is "", it's fine. We'll replace {successorAlias} with "".
		command = strings.Replace(command, "{successorAlias}", topologyRecovery.SuccessorAlias, -1)
	}

	command = strings.Replace(command, "{lostSlaves}", topologyRecovery.LostReplicas.ToCommaDelimitedList(), -1)
	command = strings.Replace(command, "{lostReplicas}", topologyRecovery.LostReplicas.ToCommaDelimitedList(), -1)
	command = strings.Replace(command, "{countLostReplicas}", fmt.Sprintf("%d", len(topologyRecovery.LostReplicas)), -1)
	command = strings.Replace(command, "{slaveHosts}", analysisEntry.Downstreams.ToCommaDelimitedList(), -1)
	command = strings.Replace(command, "{replicaHosts}", analysisEntry.Downstreams.ToCommaDelimitedList(), -1)

	return command, async
}

func ExecuteProcess(command string, env []string, topologyRecovery *dtstruct.TopologyRecovery, fullDescription string) (err error) {
	// Log the command to be run and record how long it takes as this may be useful
	AuditTopologyRecovery(topologyRecovery, fmt.Sprintf("Running %s: %s", fullDescription, command))
	start := time.Now()
	var info string
	if err = osp.CommandRun(command, env); err == nil {
		info = fmt.Sprintf("Completed %s in %v", fullDescription, time.Since(start))
	} else {
		info = fmt.Sprintf("Execution of %s failed in %v with error: %v", fullDescription, time.Since(start), err)
		log.Errorf(info)
	}
	AuditTopologyRecovery(topologyRecovery, info)
	return err
}