// Copyright (c) 2015-2021 MinIO, Inc.
//
// This file is part of MinIO Object Storage stack
//
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU Affero General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU Affero General Public License for more details.
//
// You should have received a copy of the GNU Affero General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.

package cmd

import (
	"time"
)

// DeleteOptions represents the disk level delete options available for the APIs
//
//msgp:ignore DeleteOptions
type DeleteOptions struct {
	Recursive bool
	Force     bool
}

//go:generate msgp -file=$GOFILE

// DiskInfo is an extended type which returns current
// disk usage per path.
// The above means that any added/deleted fields are incompatible.
//
// The above means that any added/deleted fields are incompatible.
//
//msgp:tuple DiskInfo
type DiskInfo struct {
	Total      uint64
	Free       uint64
	Used       uint64
	UsedInodes uint64
	FreeInodes uint64
	Major      uint32
	Minor      uint32
	FSType     string
	RootDisk   bool
	Healing    bool
	Scanning   bool
	Endpoint   string
	MountPath  string
	ID         string
	Metrics    DiskMetrics
	Error      string // carries the error over the network
}

// DiskMetrics has the information about XL Storage APIs
// the number of calls of each API and the moving average of
// the duration of each API.
type DiskMetrics struct {
	LastMinute map[string]AccElem `json:"apiLatencies,omitempty"`
	APICalls   map[string]uint64  `json:"apiCalls,omitempty"`
}

// VolsInfo is a collection of volume(bucket) information
type VolsInfo []VolInfo

// VolInfo - represents volume stat information.
// The above means that any added/deleted fields are incompatible.
//
// The above means that any added/deleted fields are incompatible.
//
//msgp:tuple VolInfo
type VolInfo struct {
	// Name of the volume.
	Name string

	// Date and time when the volume was created.
	Created time.Time
}

// FilesInfo represent a list of files, additionally
// indicates if the list is last.
//
//msgp:tuple FileInfo
type FilesInfo struct {
	Files       []FileInfo
	IsTruncated bool
}

// Size returns size of all versions for the object 'Name'
func (f FileInfoVersions) Size() (size int64) {
	for _, v := range f.Versions {
		size += v.Size
	}
	return size
}

// FileInfoVersions represent a list of versions for a given file.
// The above means that any added/deleted fields are incompatible.
//
// The above means that any added/deleted fields are incompatible.
//
//msgp:tuple FileInfoVersions
type FileInfoVersions struct {
	// Name of the volume.
	Volume string `msg:"v,omitempty"`

	// Name of the file.
	Name string `msg:"n,omitempty"`

	// Represents the latest mod time of the
	// latest version.
	LatestModTime time.Time `msg:"lm"`

	Versions     []FileInfo `msg:"vs"`
	FreeVersions []FileInfo `msg:"fvs"`
}

// findVersionIndex will return the version index where the version
// was found. Returns -1 if not found.
func (f *FileInfoVersions) findVersionIndex(v string) int {
	if f == nil || v == "" {
		return -1
	}
	for i, ver := range f.Versions {
		if ver.VersionID == v {
			return i
		}
	}
	return -1
}

// RawFileInfo - represents raw file stat information as byte array.
// The above means that any added/deleted fields are incompatible.
// Make sure to bump the internode version at storage-rest-common.go
type RawFileInfo struct {
	// Content of entire xl.meta (may contain data depending on what was requested by the caller.
	Buf []byte `msg:"b"`

	// DiskMTime indicates the mtime of the xl.meta on disk
	// This is mainly used for detecting a particular issue
	// reported in https://github.com/minio/minio/pull/13803
	DiskMTime time.Time `msg:"dmt"`
}

// FileInfo - represents file stat information.
// The above means that any added/deleted fields are incompatible.
// Make sure to bump the internode version at storage-rest-common.go
type FileInfo struct {
	// Name of the volume.
	Volume string `msg:"v,omitempty"`

	// Name of the file.
	Name string `msg:"n,omitempty"`

	// Version of the file.
	VersionID string `msg:"vid,omitempty"`

	// Indicates if the version is the latest
	IsLatest bool `msg:"is"`

	// Deleted is set when this FileInfo represents
	// a deleted marker for a versioned bucket.
	Deleted bool `msg:"del"`

	// TransitionStatus is set to Pending/Complete for transitioned
	// entries based on state of transition
	TransitionStatus string `msg:"ts"`
	// TransitionedObjName is the object name on the remote tier corresponding
	// to object (version) on the source tier.
	TransitionedObjName string `msg:"to"`
	// TransitionTier is the storage class label assigned to remote tier.
	TransitionTier string `msg:"tt"`
	// TransitionVersionID stores a version ID of the object associate
	// with the remote tier.
	TransitionVersionID string `msg:"tv"`
	// ExpireRestored indicates that the restored object is to be expired.
	ExpireRestored bool `msg:"exp"`

	// DataDir of the file
	DataDir string `msg:"dd"`

	// Indicates if this object is still in V1 format.
	XLV1 bool `msg:"v1"`

	// Date and time when the file was last modified, if Deleted
	// is 'true' this value represents when while was deleted.
	ModTime time.Time `msg:"mt"`

	// Total file size.
	Size int64 `msg:"sz"`

	// File mode bits.
	Mode uint32 `msg:"m"`

	// WrittenByVersion is the unix time stamp of the MinIO
	// version that created this version of the object.
	WrittenByVersion uint64 `msg:"wv"`

	// File metadata
	Metadata map[string]string `msg:"meta"`

	// All the parts per object.
	Parts []ObjectPartInfo `msg:"parts"`

	// Erasure info for all objects.
	Erasure ErasureInfo `msg:"ei"`

	MarkDeleted      bool             `msg:"md"` // mark this version as deleted
	ReplicationState ReplicationState `msg:"rs"` // Internal replication state to be passed back in ObjectInfo

	Data []byte `msg:"d,allownil"` // optionally carries object data

	NumVersions      int       `msg:"nv"`
	SuccessorModTime time.Time `msg:"smt"`

	Fresh bool `msg:"fr"` // indicates this is a first time call to write FileInfo.

	// Position of this version or object in a multi-object delete call,
	// no other caller must set this value other than multi-object delete call.
	// usage in other calls in undefined please avoid.
	Idx int `msg:"i"`

	// DiskMTime indicates the mtime of the xl.meta on disk
	// This is mainly used for detecting a particular issue
	// reported in https://github.com/minio/minio/pull/13803
	DiskMTime time.Time `msg:"dmt"`

	// Combined checksum when object was uploaded.
	Checksum []byte `msg:"cs,allownil"`
}

// WriteQuorum returns expected write quorum for this FileInfo
func (fi FileInfo) WriteQuorum(dquorum int) int {
	if fi.Deleted {
		return dquorum
	}
	quorum := fi.Erasure.DataBlocks
	if fi.Erasure.DataBlocks == fi.Erasure.ParityBlocks {
		quorum++
	}
	return quorum
}

// ReadQuorum returns expected read quorum for this FileInfo
func (fi FileInfo) ReadQuorum(dquorum int) int {
	if fi.Deleted {
		return dquorum
	}
	return fi.Erasure.DataBlocks
}

// Equals checks if fi(FileInfo) matches ofi(FileInfo)
func (fi FileInfo) Equals(ofi FileInfo) (ok bool) {
	if !fi.MetadataEquals(ofi) {
		return false
	}
	if !fi.ReplicationInfoEquals(ofi) {
		return false
	}
	if !fi.TransitionInfoEquals(ofi) {
		return false
	}
	return fi.ModTime.Equal(ofi.ModTime)
}

// GetDataDir returns an expected dataDir given FileInfo
//   - deleteMarker returns "delete-marker"
//   - returns "legacy" if FileInfo is XLV1 and DataDir is
//     empty, returns DataDir otherwise
//   - returns "dataDir"
func (fi FileInfo) GetDataDir() string {
	if fi.Deleted {
		return "delete-marker"
	}
	if fi.XLV1 && fi.DataDir == "" {
		return "legacy"
	}
	return fi.DataDir
}

// InlineData returns true if object contents are inlined alongside its metadata.
func (fi FileInfo) InlineData() bool {
	_, ok := fi.Metadata[ReservedMetadataPrefixLower+"inline-data"]
	return ok
}

// SetInlineData marks object (version) as inline.
func (fi *FileInfo) SetInlineData() {
	if fi.Metadata == nil {
		fi.Metadata = make(map[string]string, 1)
	}
	fi.Metadata[ReservedMetadataPrefixLower+"inline-data"] = "true"
}

// VersionPurgeStatusKey denotes purge status in metadata
const (
	VersionPurgeStatusKey = ReservedMetadataPrefixLower + "purgestatus"
)

// newFileInfo - initializes new FileInfo, allocates a fresh erasure info.
func newFileInfo(object string, dataBlocks, parityBlocks int) (fi FileInfo) {
	fi.Erasure = ErasureInfo{
		Algorithm:    erasureAlgorithm,
		DataBlocks:   dataBlocks,
		ParityBlocks: parityBlocks,
		BlockSize:    blockSizeV2,
		Distribution: hashOrder(object, dataBlocks+parityBlocks),
	}
	return fi
}

// ReadMultipleReq contains information of multiple files to read from disk.
type ReadMultipleReq struct {
	Bucket       string   // Bucket. Can be empty if multiple buckets.
	Prefix       string   // Shared prefix of all files. Can be empty. Will be joined to filename without modification.
	Files        []string // Individual files to read.
	MaxSize      int64    // Return error if size is exceed.
	MetadataOnly bool     // Read as XL meta and truncate data.
	AbortOn404   bool     // Stop reading after first file not found.
	MaxResults   int      // Stop after this many successful results. <= 0 means all.
}

// ReadMultipleResp contains a single response from a ReadMultipleReq.
type ReadMultipleResp struct {
	Bucket  string    // Bucket as given by request.
	Prefix  string    // Prefix as given by request.
	File    string    // File name as given in request.
	Exists  bool      // Returns whether the file existed on disk.
	Error   string    // Returns any error when reading.
	Data    []byte    // Contains all data of file.
	Modtime time.Time // Modtime of file on disk.
}