// Copyright GoFrame Author(https://goframe.org). All Rights Reserved.
//
// This Source Code Form is subject to the terms of the MIT License.
// If a copy of the MIT was not distributed with this file,
// You can obtain one at https://github.com/gogf/gf.

package gerror

import (
	"bytes"
	"fmt"
)

// Stack returns the stack callers as string.
// It returns an empty string if the `err` does not support stacks.
func (err *Error) Stack() string {
	if err == nil {
		return ""
	}
	var (
		loop   = err
		index  = 1
		buffer = bytes.NewBuffer(nil)
	)
	for loop != nil {
		buffer.WriteString(fmt.Sprintf("%d. %-v\n", index, loop))
		index++
		formatSubStack(loop.stack, buffer)
		if loop.error != nil {
			if e, ok := loop.error.(*Error); ok {
				loop = e
			} else {
				buffer.WriteString(fmt.Sprintf("%d. %s\n", index, loop.error.Error()))
				index++
				break
			}
		} else {
			break
		}
	}
	return buffer.String()
}