/*
 * Minio Cloud Storage, (C) 2015 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 (
	"encoding/xml"
	"net/http"
)

// APIError structure
type APIError struct {
	Code           string
	Description    string
	HTTPStatusCode int
}

// APIErrorResponse - error response format
type APIErrorResponse struct {
	XMLName    xml.Name `xml:"Error" json:"-"`
	Code       string
	Message    string
	Key        string
	BucketName string
	Resource   string
	RequestID  string `xml:"RequestId"`
	HostID     string `xml:"HostId"`
}

// APIErrorCode type of error status.
type APIErrorCode int

// Error codes, non exhaustive list - http://docs.aws.amazon.com/AmazonS3/latest/API/ErrorResponses.html
const (
	ErrNone APIErrorCode = iota
	ErrAccessDenied
	ErrBadDigest
	ErrEntityTooSmall
	ErrEntityTooLarge
	ErrIncompleteBody
	ErrInternalError
	ErrInvalidAccessKeyID
	ErrInvalidBucketName
	ErrInvalidDigest
	ErrInvalidRange
	ErrInvalidCopyPartRange
	ErrInvalidCopyPartRangeSource
	ErrInvalidMaxKeys
	ErrInvalidMaxUploads
	ErrInvalidMaxParts
	ErrInvalidPartNumberMarker
	ErrInvalidRequestBody
	ErrInvalidCopySource
	ErrInvalidMetadataDirective
	ErrInvalidCopyDest
	ErrInvalidPolicyDocument
	ErrInvalidObjectState
	ErrMalformedXML
	ErrMissingContentLength
	ErrMissingContentMD5
	ErrMissingRequestBodyError
	ErrNoSuchBucket
	ErrNoSuchBucketPolicy
	ErrNoSuchKey
	ErrNoSuchUpload
	ErrNotImplemented
	ErrPreconditionFailed
	ErrRequestTimeTooSkewed
	ErrSignatureDoesNotMatch
	ErrMethodNotAllowed
	ErrInvalidPart
	ErrInvalidPartOrder
	ErrAuthorizationHeaderMalformed
	ErrMalformedPOSTRequest
	ErrPOSTFileRequired
	ErrSignatureVersionNotSupported
	ErrBucketNotEmpty
	ErrAllAccessDisabled
	ErrMalformedPolicy
	ErrMissingFields
	ErrMissingCredTag
	ErrCredMalformed
	ErrInvalidRegion
	ErrInvalidService
	ErrInvalidRequestVersion
	ErrMissingSignTag
	ErrMissingSignHeadersTag
	ErrPolicyAlreadyExpired
	ErrMalformedDate
	ErrMalformedPresignedDate
	ErrMalformedCredentialDate
	ErrMalformedCredentialRegion
	ErrMalformedExpires
	ErrNegativeExpires
	ErrAuthHeaderEmpty
	ErrExpiredPresignRequest
	ErrRequestNotReadyYet
	ErrUnsignedHeaders
	ErrMissingDateHeader
	ErrInvalidQuerySignatureAlgo
	ErrInvalidQueryParams
	ErrBucketAlreadyOwnedByYou
	ErrInvalidDuration
	ErrNotSupported
	ErrBucketAlreadyExists
	// Add new error codes here.

	// Bucket notification related errors.
	ErrEventNotification
	ErrARNNotification
	ErrRegionNotification
	ErrOverlappingFilterNotification
	ErrFilterNameInvalid
	ErrFilterNamePrefix
	ErrFilterNameSuffix
	ErrFilterValueInvalid
	ErrOverlappingConfigs

	// S3 extended errors.
	ErrContentSHA256Mismatch

	// Add new extended error codes here.

	// Minio extended errors.
	ErrReadQuorum
	ErrWriteQuorum
	ErrStorageFull
	ErrObjectExistsAsDirectory
	ErrPolicyNesting
	ErrInvalidObjectName
	ErrInvalidResourceName
	ErrServerNotInitialized
	// Add new extended error codes here.
	// Please open a https://github.com/minio/minio/issues before adding
	// new error codes here.

	ErrAdminInvalidAccessKey
	ErrAdminInvalidSecretKey
	ErrAdminConfigNoQuorum
	ErrInsecureClientRequest
)

// error code to APIError structure, these fields carry respective
// descriptions for all the error responses.
var errorCodeResponse = map[APIErrorCode]APIError{
	ErrInvalidCopyDest: {
		Code:           "InvalidRequest",
		Description:    "This copy request is illegal because it is trying to copy an object to itself without changing the object's metadata, storage class, website redirect location or encryption attributes.",
		HTTPStatusCode: http.StatusBadRequest,
	},
	ErrInvalidCopySource: {
		Code:           "InvalidArgument",
		Description:    "Copy Source must mention the source bucket and key: sourcebucket/sourcekey.",
		HTTPStatusCode: http.StatusBadRequest,
	},
	ErrInvalidMetadataDirective: {
		Code:           "InvalidArgument",
		Description:    "Unknown metadata directive.",
		HTTPStatusCode: http.StatusBadRequest,
	},
	ErrInvalidRequestBody: {
		Code:           "InvalidArgument",
		Description:    "Body shouldn't be set for this request.",
		HTTPStatusCode: http.StatusBadRequest,
	},
	ErrInvalidMaxUploads: {
		Code:           "InvalidArgument",
		Description:    "Argument max-uploads must be an integer between 0 and 2147483647",
		HTTPStatusCode: http.StatusBadRequest,
	},
	ErrInvalidMaxKeys: {
		Code:           "InvalidArgument",
		Description:    "Argument maxKeys must be an integer between 0 and 2147483647",
		HTTPStatusCode: http.StatusBadRequest,
	},
	ErrInvalidMaxParts: {
		Code:           "InvalidArgument",
		Description:    "Argument max-parts must be an integer between 0 and 2147483647",
		HTTPStatusCode: http.StatusBadRequest,
	},
	ErrInvalidPartNumberMarker: {
		Code:           "InvalidArgument",
		Description:    "Argument partNumberMarker must be an integer.",
		HTTPStatusCode: http.StatusBadRequest,
	},
	ErrInvalidPolicyDocument: {
		Code:           "InvalidPolicyDocument",
		Description:    "The content of the form does not meet the conditions specified in the policy document.",
		HTTPStatusCode: http.StatusBadRequest,
	},
	ErrAccessDenied: {
		Code:           "AccessDenied",
		Description:    "Access Denied.",
		HTTPStatusCode: http.StatusForbidden,
	},
	ErrBadDigest: {
		Code:           "BadDigest",
		Description:    "The Content-Md5 you specified did not match what we received.",
		HTTPStatusCode: http.StatusBadRequest,
	},
	ErrEntityTooSmall: {
		Code:           "EntityTooSmall",
		Description:    "Your proposed upload is smaller than the minimum allowed object size.",
		HTTPStatusCode: http.StatusBadRequest,
	},
	ErrEntityTooLarge: {
		Code:           "EntityTooLarge",
		Description:    "Your proposed upload exceeds the maximum allowed object size.",
		HTTPStatusCode: http.StatusBadRequest,
	},
	ErrIncompleteBody: {
		Code:           "IncompleteBody",
		Description:    "You did not provide the number of bytes specified by the Content-Length HTTP header.",
		HTTPStatusCode: http.StatusBadRequest,
	},
	ErrInternalError: {
		Code:           "InternalError",
		Description:    "We encountered an internal error, please try again.",
		HTTPStatusCode: http.StatusInternalServerError,
	},
	ErrInvalidAccessKeyID: {
		Code:           "InvalidAccessKeyId",
		Description:    "The access key ID you provided does not exist in our records.",
		HTTPStatusCode: http.StatusForbidden,
	},
	ErrInvalidBucketName: {
		Code:           "InvalidBucketName",
		Description:    "The specified bucket is not valid.",
		HTTPStatusCode: http.StatusBadRequest,
	},
	ErrInvalidDigest: {
		Code:           "InvalidDigest",
		Description:    "The Content-Md5 you specified is not valid.",
		HTTPStatusCode: http.StatusBadRequest,
	},
	ErrInvalidRange: {
		Code:           "InvalidRange",
		Description:    "The requested range is not satisfiable",
		HTTPStatusCode: http.StatusRequestedRangeNotSatisfiable,
	},
	ErrMalformedXML: {
		Code:           "MalformedXML",
		Description:    "The XML you provided was not well-formed or did not validate against our published schema.",
		HTTPStatusCode: http.StatusBadRequest,
	},
	ErrMissingContentLength: {
		Code:           "MissingContentLength",
		Description:    "You must provide the Content-Length HTTP header.",
		HTTPStatusCode: http.StatusLengthRequired,
	},
	ErrMissingContentMD5: {
		Code:           "MissingContentMD5",
		Description:    "Missing required header for this request: Content-Md5.",
		HTTPStatusCode: http.StatusBadRequest,
	},
	ErrMissingRequestBodyError: {
		Code:           "MissingRequestBodyError",
		Description:    "Request body is empty.",
		HTTPStatusCode: http.StatusLengthRequired,
	},
	ErrNoSuchBucket: {
		Code:           "NoSuchBucket",
		Description:    "The specified bucket does not exist",
		HTTPStatusCode: http.StatusNotFound,
	},
	ErrNoSuchBucketPolicy: {
		Code:           "NoSuchBucketPolicy",
		Description:    "The bucket policy does not exist",
		HTTPStatusCode: http.StatusNotFound,
	},
	ErrNoSuchKey: {
		Code:           "NoSuchKey",
		Description:    "The specified key does not exist.",
		HTTPStatusCode: http.StatusNotFound,
	},
	ErrNoSuchUpload: {
		Code:           "NoSuchUpload",
		Description:    "The specified multipart upload does not exist. The upload ID may be invalid, or the upload may have been aborted or completed.",
		HTTPStatusCode: http.StatusNotFound,
	},
	ErrNotImplemented: {
		Code:           "NotImplemented",
		Description:    "A header you provided implies functionality that is not implemented",
		HTTPStatusCode: http.StatusNotImplemented,
	},
	ErrPreconditionFailed: {
		Code:           "PreconditionFailed",
		Description:    "At least one of the pre-conditions you specified did not hold",
		HTTPStatusCode: http.StatusPreconditionFailed,
	},
	ErrRequestTimeTooSkewed: {
		Code:           "RequestTimeTooSkewed",
		Description:    "The difference between the request time and the server's time is too large.",
		HTTPStatusCode: http.StatusForbidden,
	},
	ErrSignatureDoesNotMatch: {
		Code:           "SignatureDoesNotMatch",
		Description:    "The request signature we calculated does not match the signature you provided. Check your key and signing method.",
		HTTPStatusCode: http.StatusForbidden,
	},
	ErrMethodNotAllowed: {
		Code:           "MethodNotAllowed",
		Description:    "The specified method is not allowed against this resource.",
		HTTPStatusCode: http.StatusMethodNotAllowed,
	},
	ErrInvalidPart: {
		Code:           "InvalidPart",
		Description:    "One or more of the specified parts could not be found.",
		HTTPStatusCode: http.StatusBadRequest,
	},
	ErrInvalidPartOrder: {
		Code:           "InvalidPartOrder",
		Description:    "The list of parts was not in ascending order. The parts list must be specified in order by part number.",
		HTTPStatusCode: http.StatusBadRequest,
	},
	ErrInvalidObjectState: {
		Code:           "InvalidObjectState",
		Description:    "The operation is not valid for the current state of the object.",
		HTTPStatusCode: http.StatusForbidden,
	},
	ErrAuthorizationHeaderMalformed: {
		Code:           "AuthorizationHeaderMalformed",
		Description:    "The authorization header is malformed; the region is wrong; expecting 'us-east-1'.",
		HTTPStatusCode: http.StatusBadRequest,
	},
	ErrMalformedPOSTRequest: {
		Code:           "MalformedPOSTRequest",
		Description:    "The body of your POST request is not well-formed multipart/form-data.",
		HTTPStatusCode: http.StatusBadRequest,
	},
	ErrPOSTFileRequired: {
		Code:           "InvalidArgument",
		Description:    "POST requires exactly one file upload per request.",
		HTTPStatusCode: http.StatusBadRequest,
	},
	ErrSignatureVersionNotSupported: {
		Code:           "InvalidRequest",
		Description:    "The authorization mechanism you have provided is not supported. Please use AWS4-HMAC-SHA256.",
		HTTPStatusCode: http.StatusBadRequest,
	},
	ErrBucketNotEmpty: {
		Code:           "BucketNotEmpty",
		Description:    "The bucket you tried to delete is not empty",
		HTTPStatusCode: http.StatusConflict,
	},
	ErrBucketAlreadyExists: {
		Code:           "BucketAlreadyExists",
		Description:    "The requested bucket name is not available. The bucket namespace is shared by all users of the system. Please select a different name and try again.",
		HTTPStatusCode: http.StatusConflict,
	},
	ErrAllAccessDisabled: {
		Code:           "AllAccessDisabled",
		Description:    "All access to this bucket has been disabled.",
		HTTPStatusCode: http.StatusForbidden,
	},
	ErrMalformedPolicy: {
		Code:           "MalformedPolicy",
		Description:    "Policy has invalid resource.",
		HTTPStatusCode: http.StatusBadRequest,
	},
	ErrMissingFields: {
		Code:           "MissingFields",
		Description:    "Missing fields in request.",
		HTTPStatusCode: http.StatusBadRequest,
	},
	ErrMissingCredTag: {
		Code:           "InvalidRequest",
		Description:    "Missing Credential field for this request.",
		HTTPStatusCode: http.StatusBadRequest,
	},
	ErrCredMalformed: {
		Code:           "AuthorizationQueryParametersError",
		Description:    "Error parsing the X-Amz-Credential parameter; the Credential is mal-formed; expecting \"<YOUR-AKID>/YYYYMMDD/REGION/SERVICE/aws4_request\".",
		HTTPStatusCode: http.StatusBadRequest,
	},
	ErrMalformedDate: {
		Code:           "MalformedDate",
		Description:    "Invalid date format header, expected to be in ISO8601, RFC1123 or RFC1123Z time format.",
		HTTPStatusCode: http.StatusBadRequest,
	},
	ErrMalformedPresignedDate: {
		Code:           "AuthorizationQueryParametersError",
		Description:    "X-Amz-Date must be in the ISO8601 Long Format \"yyyyMMdd'T'HHmmss'Z'\"",
		HTTPStatusCode: http.StatusBadRequest,
	},
	// FIXME: Should contain the invalid param set as seen in https://github.com/minio/minio/issues/2385.
	// right Description:    "Error parsing the X-Amz-Credential parameter; incorrect date format \"%s\". This date in the credential must be in the format \"yyyyMMdd\".",
	// Need changes to make sure variable messages can be constructed.
	ErrMalformedCredentialDate: {
		Code:           "AuthorizationQueryParametersError",
		Description:    "Error parsing the X-Amz-Credential parameter; incorrect date format \"%s\". This date in the credential must be in the format \"yyyyMMdd\".",
		HTTPStatusCode: http.StatusBadRequest,
	},
	// FIXME: Should contain the invalid param set as seen in https://github.com/minio/minio/issues/2385.
	// right Description:    "Error parsing the X-Amz-Credential parameter; the region 'us-east-' is wrong; expecting 'us-east-1'".
	// Need changes to make sure variable messages can be constructed.
	ErrMalformedCredentialRegion: {
		Code:           "AuthorizationQueryParametersError",
		Description:    "Error parsing the X-Amz-Credential parameter; the region is wrong;",
		HTTPStatusCode: http.StatusBadRequest,
	},
	ErrInvalidRegion: {
		Code:           "InvalidRegion",
		Description:    "Region does not match.",
		HTTPStatusCode: http.StatusBadRequest,
	},
	// FIXME: Should contain the invalid param set as seen in https://github.com/minio/minio/issues/2385.
	// right Description:   "Error parsing the X-Amz-Credential parameter; incorrect service \"s4\". This endpoint belongs to \"s3\".".
	// Need changes to make sure variable messages can be constructed.
	ErrInvalidService: {
		Code:           "AuthorizationQueryParametersError",
		Description:    "Error parsing the X-Amz-Credential parameter; incorrect service. This endpoint belongs to \"s3\".",
		HTTPStatusCode: http.StatusBadRequest,
	},
	// FIXME: Should contain the invalid param set as seen in https://github.com/minio/minio/issues/2385.
	// Description:   "Error parsing the X-Amz-Credential parameter; incorrect terminal "aws4_reque". This endpoint uses "aws4_request".
	// Need changes to make sure variable messages can be constructed.
	ErrInvalidRequestVersion: {
		Code:           "AuthorizationQueryParametersError",
		Description:    "Error parsing the X-Amz-Credential parameter; incorrect terminal. This endpoint uses \"aws4_request\".",
		HTTPStatusCode: http.StatusBadRequest,
	},
	ErrMissingSignTag: {
		Code:           "AccessDenied",
		Description:    "Signature header missing Signature field.",
		HTTPStatusCode: http.StatusBadRequest,
	},
	ErrMissingSignHeadersTag: {
		Code:           "InvalidArgument",
		Description:    "Signature header missing SignedHeaders field.",
		HTTPStatusCode: http.StatusBadRequest,
	},
	ErrPolicyAlreadyExpired: {
		Code:           "AccessDenied",
		Description:    "Invalid according to Policy: Policy expired.",
		HTTPStatusCode: http.StatusBadRequest,
	},
	ErrMalformedExpires: {
		Code:           "AuthorizationQueryParametersError",
		Description:    "X-Amz-Expires should be a number",
		HTTPStatusCode: http.StatusBadRequest,
	},
	ErrNegativeExpires: {
		Code:           "AuthorizationQueryParametersError",
		Description:    "X-Amz-Expires must be non-negative",
		HTTPStatusCode: http.StatusBadRequest,
	},
	ErrAuthHeaderEmpty: {
		Code:           "InvalidArgument",
		Description:    "Authorization header is invalid -- one and only one ' ' (space) required.",
		HTTPStatusCode: http.StatusBadRequest,
	},
	ErrMissingDateHeader: {
		Code:           "AccessDenied",
		Description:    "AWS authentication requires a valid Date or x-amz-date header",
		HTTPStatusCode: http.StatusBadRequest,
	},
	ErrInvalidQuerySignatureAlgo: {
		Code:           "AuthorizationQueryParametersError",
		Description:    "X-Amz-Algorithm only supports \"AWS4-HMAC-SHA256\".",
		HTTPStatusCode: http.StatusBadRequest,
	},
	ErrExpiredPresignRequest: {
		Code:           "AccessDenied",
		Description:    "Request has expired",
		HTTPStatusCode: http.StatusForbidden,
	},
	ErrRequestNotReadyYet: {
		Code:           "AccessDenied",
		Description:    "Request is not valid yet",
		HTTPStatusCode: http.StatusForbidden,
	},
	// FIXME: Actual XML error response also contains the header which missed in list of signed header parameters.
	ErrUnsignedHeaders: {
		Code:           "AccessDenied",
		Description:    "There were headers present in the request which were not signed",
		HTTPStatusCode: http.StatusBadRequest,
	},
	ErrInvalidQueryParams: {
		Code:           "AuthorizationQueryParametersError",
		Description:    "Query-string authentication version 4 requires the X-Amz-Algorithm, X-Amz-Credential, X-Amz-Signature, X-Amz-Date, X-Amz-SignedHeaders, and X-Amz-Expires parameters.",
		HTTPStatusCode: http.StatusBadRequest,
	},
	ErrBucketAlreadyOwnedByYou: {
		Code:           "BucketAlreadyOwnedByYou",
		Description:    "Your previous request to create the named bucket succeeded and you already own it.",
		HTTPStatusCode: http.StatusConflict,
	},
	ErrInvalidDuration: {
		Code:           "InvalidDuration",
		Description:    "Duration provided in the request is invalid.",
		HTTPStatusCode: http.StatusBadRequest,
	},

	/// Bucket notification related errors.
	ErrEventNotification: {
		Code:           "InvalidArgument",
		Description:    "A specified event is not supported for notifications.",
		HTTPStatusCode: http.StatusBadRequest,
	},
	ErrARNNotification: {
		Code:           "InvalidArgument",
		Description:    "A specified destination ARN does not exist or is not well-formed. Verify the destination ARN.",
		HTTPStatusCode: http.StatusBadRequest,
	},
	ErrRegionNotification: {
		Code:           "InvalidArgument",
		Description:    "A specified destination is in a different region than the bucket. You must use a destination that resides in the same region as the bucket.",
		HTTPStatusCode: http.StatusBadRequest,
	},
	ErrOverlappingFilterNotification: {
		Code:           "InvalidArgument",
		Description:    "An object key name filtering rule defined with overlapping prefixes, overlapping suffixes, or overlapping combinations of prefixes and suffixes for the same event types.",
		HTTPStatusCode: http.StatusBadRequest,
	},
	ErrFilterNameInvalid: {
		Code:           "InvalidArgument",
		Description:    "filter rule name must be either prefix or suffix",
		HTTPStatusCode: http.StatusBadRequest,
	},
	ErrFilterNamePrefix: {
		Code:           "InvalidArgument",
		Description:    "Cannot specify more than one prefix rule in a filter.",
		HTTPStatusCode: http.StatusBadRequest,
	},
	ErrFilterNameSuffix: {
		Code:           "InvalidArgument",
		Description:    "Cannot specify more than one suffix rule in a filter.",
		HTTPStatusCode: http.StatusBadRequest,
	},
	ErrFilterValueInvalid: {
		Code:           "InvalidArgument",
		Description:    "Size of filter rule value cannot exceed 1024 bytes in UTF-8 representation",
		HTTPStatusCode: http.StatusBadRequest,
	},
	ErrOverlappingConfigs: {
		Code:           "InvalidArgument",
		Description:    "Configurations overlap. Configurations on the same bucket cannot share a common event type.",
		HTTPStatusCode: http.StatusBadRequest,
	},
	ErrInvalidCopyPartRange: {
		Code:           "InvalidArgument",
		Description:    "The x-amz-copy-source-range value must be of the form bytes=first-last where first and last are the zero-based offsets of the first and last bytes to copy",
		HTTPStatusCode: http.StatusBadRequest,
	},
	ErrInvalidCopyPartRangeSource: {
		Code:           "InvalidArgument",
		Description:    "Range specified is not valid for source object",
		HTTPStatusCode: http.StatusBadRequest,
	},

	/// S3 extensions.
	ErrContentSHA256Mismatch: {
		Code:           "XAmzContentSHA256Mismatch",
		Description:    "The provided 'x-amz-content-sha256' header does not match what was computed.",
		HTTPStatusCode: http.StatusBadRequest,
	},

	/// Minio extensions.
	ErrStorageFull: {
		Code:           "XMinioStorageFull",
		Description:    "Storage backend has reached its minimum free disk threshold. Please delete few objects to proceed.",
		HTTPStatusCode: http.StatusInternalServerError,
	},
	ErrObjectExistsAsDirectory: {
		Code:           "XMinioObjectExistsAsDirectory",
		Description:    "Object name already exists as a directory.",
		HTTPStatusCode: http.StatusConflict,
	},
	ErrReadQuorum: {
		Code:           "XMinioReadQuorum",
		Description:    "Multiple disk failures, unable to reconstruct data.",
		HTTPStatusCode: http.StatusServiceUnavailable,
	},
	ErrWriteQuorum: {
		Code:           "XMinioWriteQuorum",
		Description:    "Multiple disks failures, unable to write data.",
		HTTPStatusCode: http.StatusServiceUnavailable,
	},
	ErrPolicyNesting: {
		Code:           "XMinioPolicyNesting",
		Description:    "New bucket policy conflicts with an existing policy. Please try again with new prefix.",
		HTTPStatusCode: http.StatusConflict,
	},
	ErrInvalidObjectName: {
		Code:           "XMinioInvalidObjectName",
		Description:    "Object name contains unsupported characters.",
		HTTPStatusCode: http.StatusBadRequest,
	},
	ErrInvalidResourceName: {
		Code:           "XMinioInvalidResourceName",
		Description:    "Resource name contains bad components such as \"..\" or \".\".",
		HTTPStatusCode: http.StatusBadRequest,
	},
	ErrServerNotInitialized: {
		Code:           "XMinioServerNotInitialized",
		Description:    "Server not initialized, please try again.",
		HTTPStatusCode: http.StatusServiceUnavailable,
	},
	ErrAdminInvalidAccessKey: {
		Code:           "XMinioAdminInvalidAccessKey",
		Description:    "The access key is invalid.",
		HTTPStatusCode: http.StatusBadRequest,
	},
	ErrAdminInvalidSecretKey: {
		Code:           "XMinioAdminInvalidSecretKey",
		Description:    "The secret key is invalid.",
		HTTPStatusCode: http.StatusBadRequest,
	},
	ErrAdminConfigNoQuorum: {
		Code:           "XMinioAdminConfigNoQuorum",
		Description:    "Configuration update failed because server quorum was not met",
		HTTPStatusCode: http.StatusServiceUnavailable,
	},
	ErrInsecureClientRequest: {
		Code:           "XMinioInsecureClientRequest",
		Description:    "Cannot respond to plain-text request from TLS-encrypted server",
		HTTPStatusCode: http.StatusBadRequest,
	},

	// Add your error structure here.
}

// toAPIErrorCode - Converts embedded errors. Convenience
// function written to handle all cases where we have known types of
// errors returned by underlying layers.
func toAPIErrorCode(err error) (apiErr APIErrorCode) {
	if err == nil {
		return ErrNone
	}

	err = errorCause(err)
	// Verify if the underlying error is signature mismatch.
	switch err {
	case errSignatureMismatch:
		apiErr = ErrSignatureDoesNotMatch
	case errContentSHA256Mismatch:
		apiErr = ErrContentSHA256Mismatch
	case errDataTooLarge:
		apiErr = ErrEntityTooLarge
	case errDataTooSmall:
		apiErr = ErrEntityTooSmall
	case errInvalidAccessKeyLength:
		apiErr = ErrAdminInvalidAccessKey
	case errInvalidSecretKeyLength:
		apiErr = ErrAdminInvalidSecretKey
	}

	if apiErr != ErrNone {
		// If there was a match in the above switch case.
		return apiErr
	}

	switch err.(type) {
	case StorageFull:
		apiErr = ErrStorageFull
	case BadDigest:
		apiErr = ErrBadDigest
	case AllAccessDisabled:
		apiErr = ErrAllAccessDisabled
	case IncompleteBody:
		apiErr = ErrIncompleteBody
	case ObjectExistsAsDirectory:
		apiErr = ErrObjectExistsAsDirectory
	case PrefixAccessDenied:
		apiErr = ErrAccessDenied
	case BucketNameInvalid:
		apiErr = ErrInvalidBucketName
	case BucketNotFound:
		apiErr = ErrNoSuchBucket
	case BucketAlreadyOwnedByYou:
		apiErr = ErrBucketAlreadyOwnedByYou
	case BucketNotEmpty:
		apiErr = ErrBucketNotEmpty
	case BucketAlreadyExists:
		apiErr = ErrBucketAlreadyExists
	case BucketExists:
		apiErr = ErrBucketAlreadyOwnedByYou
	case ObjectNotFound:
		apiErr = ErrNoSuchKey
	case ObjectNameInvalid:
		apiErr = ErrInvalidObjectName
	case InvalidUploadID:
		apiErr = ErrNoSuchUpload
	case InvalidPart:
		apiErr = ErrInvalidPart
	case InsufficientWriteQuorum:
		apiErr = ErrWriteQuorum
	case InsufficientReadQuorum:
		apiErr = ErrReadQuorum
	case UnsupportedDelimiter:
		apiErr = ErrNotImplemented
	case InvalidMarkerPrefixCombination:
		apiErr = ErrNotImplemented
	case InvalidUploadIDKeyCombination:
		apiErr = ErrNotImplemented
	case MalformedUploadID:
		apiErr = ErrNoSuchUpload
	case PartTooSmall:
		apiErr = ErrEntityTooSmall
	case SignatureDoesNotMatch:
		apiErr = ErrSignatureDoesNotMatch
	case SHA256Mismatch:
		apiErr = ErrContentSHA256Mismatch
	case ObjectTooLarge:
		apiErr = ErrEntityTooLarge
	case ObjectTooSmall:
		apiErr = ErrEntityTooSmall
	case NotSupported:
		apiErr = ErrNotSupported
	case NotImplemented:
		apiErr = ErrNotImplemented
	case PolicyNotFound:
		apiErr = ErrNoSuchBucketPolicy
	default:
		apiErr = ErrInternalError
	}

	return apiErr
}

// getAPIError provides API Error for input API error code.
func getAPIError(code APIErrorCode) APIError {
	return errorCodeResponse[code]
}

// getErrorResponse gets in standard error and resource value and
// provides a encodable populated response values
func getAPIErrorResponse(err APIError, resource string) APIErrorResponse {
	return APIErrorResponse{
		Code:      err.Code,
		Message:   err.Description,
		Resource:  resource,
		RequestID: "3L137",
		HostID:    "3L137",
	}
}
