/*
 * MinIO Cloud Storage, (C) 2015-2020 MinIO, Inc.
 *
 * 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 cmd

import "errors"

// errUnexpected - unexpected error, requires manual intervention.
var errUnexpected = StorageErr("unexpected error, please report this issue at https://github.com/minio/minio/issues")

// errCorruptedFormat - corrupted backend format.
var errCorruptedFormat = StorageErr("corrupted backend format, specified disk mount has unexpected previous content")

// errUnformattedDisk - unformatted disk found.
var errUnformattedDisk = StorageErr("unformatted disk found")

// errInconsistentDisk - inconsistent disk found.
var errInconsistentDisk = StorageErr("inconsistent disk found")

// errUnsupporteDisk - when disk does not support O_DIRECT flag.
var errUnsupportedDisk = StorageErr("disk does not support O_DIRECT")

// errDiskFull - cannot create volume or files when disk is full.
var errDiskFull = StorageErr("disk path full")

// errDiskNotDir - cannot use storage disk if its not a directory
var errDiskNotDir = StorageErr("disk is not directory or mountpoint")

// errDiskNotFound - cannot find the underlying configured disk anymore.
var errDiskNotFound = StorageErr("disk not found")

// errFaultyRemoteDisk - remote disk is faulty.
var errFaultyRemoteDisk = StorageErr("remote disk is faulty")

// errFaultyDisk - disk is faulty.
var errFaultyDisk = StorageErr("disk is faulty")

// errDiskAccessDenied - we don't have write permissions on disk.
var errDiskAccessDenied = StorageErr("disk access denied")

// errFileNotFound - cannot find the file.
var errFileNotFound = StorageErr("file not found")

// errFileNotFound - cannot find requested file version.
var errFileVersionNotFound = StorageErr("file version not found")

// errTooManyOpenFiles - too many open files.
var errTooManyOpenFiles = StorageErr("too many open files, please increase 'ulimit -n'")

// errFileNameTooLong - given file name is too long than supported length.
var errFileNameTooLong = StorageErr("file name too long")

// errVolumeExists - cannot create same volume again.
var errVolumeExists = StorageErr("volume already exists")

// errIsNotRegular - not of regular file type.
var errIsNotRegular = StorageErr("not of regular file type")

// errPathNotFound - cannot find the path.
var errPathNotFound = StorageErr("path not found")

// errVolumeNotFound - cannot find the volume.
var errVolumeNotFound = StorageErr("volume not found")

// errVolumeNotEmpty - volume not empty.
var errVolumeNotEmpty = StorageErr("volume is not empty")

// errVolumeAccessDenied - cannot access volume, insufficient permissions.
var errVolumeAccessDenied = StorageErr("volume access denied")

// errFileAccessDenied - cannot access file, insufficient permissions.
var errFileAccessDenied = StorageErr("file access denied")

// errFileCorrupt - file has an unexpected size, or is not readable
var errFileCorrupt = StorageErr("file is corrupted")

// errFileParentIsFile - cannot have overlapping objects, parent is already a file.
var errFileParentIsFile = StorageErr("parent is a file")

// errBitrotHashAlgoInvalid - the algo for bit-rot hash
// verification is empty or invalid.
var errBitrotHashAlgoInvalid = StorageErr("bit-rot hash algorithm is invalid")

// errCrossDeviceLink - rename across devices not allowed.
var errCrossDeviceLink = StorageErr("Rename across devices not allowed, please fix your backend configuration")

// errMinDiskSize - cannot create volume or files when disk size is less than threshold.
var errMinDiskSize = StorageErr("The disk size is less than 900MiB threshold")

// errLessData - returned when less data available than what was requested.
var errLessData = StorageErr("less data available than what was requested")

// errMoreData = returned when more data was sent by the caller than what it was supposed to.
var errMoreData = StorageErr("more data was sent than what was advertised")

// indicates readDirFn to return without further applying the fn()
var errDoneForNow = errors.New("done for now")

// errSkipFile returned by the fn() for readDirFn() when it needs
// to proceed to next entry.
var errSkipFile = errors.New("skip this file")

// StorageErr represents error generated by xlStorage call.
type StorageErr string

func (h StorageErr) Error() string {
	return string(h)
}

// Collection of basic errors.
var baseErrs = []error{
	errDiskNotFound,
	errFaultyDisk,
	errFaultyRemoteDisk,
}

var baseIgnoredErrs = baseErrs

// Is a one place function which converts all os.PathError
// into a more FS object layer friendly form, converts
// known errors into their typed form for top level
// interpretation.
func osErrToFileErr(err error) error {
	if err == nil {
		return nil
	}
	if osIsNotExist(err) {
		return errFileNotFound
	}
	if osIsPermission(err) {
		return errFileAccessDenied
	}
	if isSysErrNotDir(err) || isSysErrIsDir(err) {
		return errFileNotFound
	}
	if isSysErrPathNotFound(err) {
		return errFileNotFound
	}
	if isSysErrTooManyFiles(err) {
		return errTooManyOpenFiles
	}
	if isSysErrHandleInvalid(err) {
		return errFileNotFound
	}
	if isSysErrIO(err) {
		return errFaultyDisk
	}
	if isSysErrInvalidArg(err) {
		return errUnsupportedDisk
	}
	if isSysErrNoSpace(err) {
		return errDiskFull
	}
	return err
}
