package migrate

import (
	"time"

	"github.com/gogo/protobuf/proto"
	"github.com/influxdata/influxdb/v2/tsdb/migrate/internal"
)

//go:generate protoc --gogo_out=. internal/meta.proto

// Data represents the top level collection of all metadata.
type Data struct {
	Term      uint64 // associated raft term
	Index     uint64 // associated raft index
	ClusterID uint64
	Databases []DatabaseInfo

	MaxShardGroupID uint64
	MaxShardID      uint64
}

// unmarshal deserializes from a protobuf representation.
func (data *Data) unmarshal(pb *internal.Data) {
	data.Databases = make([]DatabaseInfo, len(pb.GetDatabases()))
	for i, x := range pb.GetDatabases() {
		data.Databases[i].unmarshal(x)
	}
}

// UnmarshalBinary decodes the object from a binary format.
func (data *Data) UnmarshalBinary(buf []byte) error {
	var pb internal.Data
	if err := proto.Unmarshal(buf, &pb); err != nil {
		return err
	}
	data.unmarshal(&pb)
	return nil
}

// DatabaseInfo represents information about a database in the system.
type DatabaseInfo struct {
	Name                   string
	DefaultRetentionPolicy string
	RetentionPolicies      []RetentionPolicyInfo
}

// unmarshal deserializes from a protobuf representation.
func (di *DatabaseInfo) unmarshal(pb *internal.DatabaseInfo) {
	di.Name = pb.GetName()
	di.DefaultRetentionPolicy = pb.GetDefaultRetentionPolicy()

	if len(pb.GetRetentionPolicies()) > 0 {
		di.RetentionPolicies = make([]RetentionPolicyInfo, len(pb.GetRetentionPolicies()))
		for i, x := range pb.GetRetentionPolicies() {
			di.RetentionPolicies[i].unmarshal(x)
		}
	}
}

// RetentionPolicyInfo represents metadata about a retention policy.
type RetentionPolicyInfo struct {
	Name               string
	ReplicaN           int
	Duration           time.Duration
	ShardGroupDuration time.Duration
}

// unmarshal deserializes from a protobuf representation.
func (rpi *RetentionPolicyInfo) unmarshal(pb *internal.RetentionPolicyInfo) {
	rpi.Name = pb.GetName()
	rpi.ReplicaN = int(pb.GetReplicaN())
	rpi.Duration = time.Duration(pb.GetDuration())
	rpi.ShardGroupDuration = time.Duration(pb.GetShardGroupDuration())
}