// Copyright 2019 The Gitea Authors. All rights reserved.
// Use of this source code is governed by a MIT-style
// license that can be found in the LICENSE file.

package setting

import (
	"encoding/json"
	"path"
	"strconv"
	"strings"
	"time"

	"code.gitea.io/gitea/modules/log"
	"code.gitea.io/gitea/modules/queue"
)

type queueSettings struct {
	DataDir          string
	Length           int
	BatchLength      int
	ConnectionString string
	Type             string
	Addresses        string
	Password         string
	DBIndex          int
	WrapIfNecessary  bool
	MaxAttempts      int
	Timeout          time.Duration
	Workers          int
}

// Queue settings
var Queue = queueSettings{}

// CreateQueue for name with provided handler and exemplar
func CreateQueue(name string, handle queue.HandlerFunc, exemplar interface{}) queue.Queue {
	q := getQueueSettings(name)
	opts := make(map[string]interface{})
	opts["QueueLength"] = q.Length
	opts["BatchLength"] = q.BatchLength
	opts["DataDir"] = q.DataDir
	opts["Addresses"] = q.Addresses
	opts["Password"] = q.Password
	opts["DBIndex"] = q.DBIndex
	opts["QueueName"] = name
	opts["Workers"] = q.Workers

	cfg, err := json.Marshal(opts)
	if err != nil {
		log.Error("Unable to marshall generic options: %v Error: %v", opts, err)
		log.Error("Unable to create queue for %s", name, err)
		return nil
	}

	returnable, err := queue.CreateQueue(queue.Type(q.Type), handle, cfg, exemplar)
	if q.WrapIfNecessary && err != nil {
		log.Warn("Unable to create queue for %s: %v", name, err)
		log.Warn("Attempting to create wrapped queue")
		returnable, err = queue.CreateQueue(queue.WrappedQueueType, handle, queue.WrappedQueueConfiguration{
			Underlying:  queue.Type(q.Type),
			Timeout:     q.Timeout,
			MaxAttempts: q.MaxAttempts,
			Config:      cfg,
			QueueLength: q.Length,
		}, exemplar)
	}
	if err != nil {
		log.Error("Unable to create queue for %s: %v", name, err)
		return nil
	}
	return returnable
}

func getQueueSettings(name string) queueSettings {
	q := queueSettings{}
	sec := Cfg.Section("queue." + name)
	// DataDir is not directly inheritable
	q.DataDir = path.Join(Queue.DataDir, name)
	for _, key := range sec.Keys() {
		switch key.Name() {
		case "DATADIR":
			q.DataDir = key.MustString(q.DataDir)
		}
	}
	if !path.IsAbs(q.DataDir) {
		q.DataDir = path.Join(AppDataPath, q.DataDir)
	}
	sec.Key("DATADIR").SetValue(q.DataDir)
	// The rest are...
	q.Length = sec.Key("LENGTH").MustInt(Queue.Length)
	q.BatchLength = sec.Key("BATCH_LENGTH").MustInt(Queue.BatchLength)
	q.ConnectionString = sec.Key("CONN_STR").MustString(Queue.ConnectionString)
	validTypes := queue.RegisteredTypesAsString()
	q.Type = sec.Key("TYPE").In(Queue.Type, validTypes)
	q.WrapIfNecessary = sec.Key("WRAP_IF_NECESSARY").MustBool(Queue.WrapIfNecessary)
	q.MaxAttempts = sec.Key("MAX_ATTEMPTS").MustInt(Queue.MaxAttempts)
	q.Timeout = sec.Key("TIMEOUT").MustDuration(Queue.Timeout)
	q.Workers = sec.Key("WORKER").MustInt(Queue.Workers)

	q.Addresses, q.Password, q.DBIndex, _ = ParseQueueConnStr(q.ConnectionString)
	return q
}

func newQueueService() {
	sec := Cfg.Section("queue")
	Queue.DataDir = sec.Key("DATADIR").MustString("queues/")
	if !path.IsAbs(Queue.DataDir) {
		Queue.DataDir = path.Join(AppDataPath, Queue.DataDir)
	}
	Queue.Length = sec.Key("LENGTH").MustInt(20)
	Queue.BatchLength = sec.Key("BATCH_LENGTH").MustInt(20)
	Queue.ConnectionString = sec.Key("CONN_STR").MustString(path.Join(AppDataPath, ""))
	validTypes := queue.RegisteredTypesAsString()
	Queue.Type = sec.Key("TYPE").In(string(queue.PersistableChannelQueueType), validTypes)
	Queue.Addresses, Queue.Password, Queue.DBIndex, _ = ParseQueueConnStr(Queue.ConnectionString)
	Queue.WrapIfNecessary = sec.Key("WRAP_IF_NECESSARY").MustBool(true)
	Queue.MaxAttempts = sec.Key("MAX_ATTEMPTS").MustInt(10)
	Queue.Timeout = sec.Key("TIMEOUT").MustDuration(GracefulHammerTime + 30*time.Second)
	Queue.Workers = sec.Key("WORKER").MustInt(1)

	Cfg.Section("queue.notification").Key("WORKER").MustInt(5)
}

// ParseQueueConnStr parses a queue connection string
func ParseQueueConnStr(connStr string) (addrs, password string, dbIdx int, err error) {
	fields := strings.Fields(connStr)
	for _, f := range fields {
		items := strings.SplitN(f, "=", 2)
		if len(items) < 2 {
			continue
		}
		switch strings.ToLower(items[0]) {
		case "addrs":
			addrs = items[1]
		case "password":
			password = items[1]
		case "db":
			dbIdx, err = strconv.Atoi(items[1])
			if err != nil {
				return
			}
		}
	}
	return
}