// Copyright 2020 The Gitea Authors. All rights reserved.
// SPDX-License-Identifier: MIT

package git

import (
	"fmt"
	"strconv"
)

// EntryMode the type of the object in the git tree
type EntryMode int

// There are only a few file modes in Git. They look like unix file modes, but they can only be
// one of these.
const (
	// EntryModeNoEntry is possible if the file was added or removed in a commit. In the case of
	// added the base commit will not have the file in its tree so a mode of 0o000000 is used.
	EntryModeNoEntry EntryMode = 0o000000
	// EntryModeBlob
	EntryModeBlob EntryMode = 0o100644
	// EntryModeExec
	EntryModeExec EntryMode = 0o100755
	// EntryModeSymlink
	EntryModeSymlink EntryMode = 0o120000
	// EntryModeCommit
	EntryModeCommit EntryMode = 0o160000
	// EntryModeTree
	EntryModeTree EntryMode = 0o040000
)

// String converts an EntryMode to a string
func (e EntryMode) String() string {
	return strconv.FormatInt(int64(e), 8)
}

// ToEntryMode converts a string to an EntryMode
func ToEntryMode(value string) EntryMode {
	v, _ := strconv.ParseInt(value, 8, 32)
	return EntryMode(v)
}

func ParseEntryMode(mode string) (EntryMode, error) {
	switch mode {
	case "000000":
		return EntryModeNoEntry, nil
	case "100644":
		return EntryModeBlob, nil
	case "100755":
		return EntryModeExec, nil
	case "120000":
		return EntryModeSymlink, nil
	case "160000":
		return EntryModeCommit, nil
	case "040000", "040755": // git uses 040000 for tree object, but some users may get 040755 for unknown reasons
		return EntryModeTree, nil
	default:
		return 0, fmt.Errorf("unparsable entry mode: %s", mode)
	}
}