/*
---------------------------------------------------------
   Project activething
   Active Thing (activething.com) git.activething.com/go

   File name  err_list.go
   Created by DEV
   Modified   23/10/2023

   Copyright 2023 activething.com
---------------------------------------------------------
// 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 errs

type ErrList []error



func (l ErrList) Clean() ErrList {
	for _, e := range l {
		if e == nil {
			return l.clean()
		}
	}
	return l
}


func (l ErrList) clean() ErrList {
	rs := make([]error, 0, len(l))
	for _, e := range l {
		if e != nil {
			rs = append(rs, e)
		}
	}
	return rs
}


func (l ErrList) GetFirst() error {
	for _, er := range l {
		if er != nil {
			return er
		}
	}
	return nil
}


func (l ErrList) GetLast() error {
	for i := len(l) - 1; i >= 0; i-- {
		if l[i] != nil {
			return l[i]
		}
	}
	return nil
}


func (l ErrList) Any() bool {
	return l.count(true) > 0 }


func (l ErrList) Count() int {
	return _errorsCount(false, l) }


func (l ErrList) count(ext bool) int {
	rs := 0
	for _, er := range l {
		if er != nil {
			if ext {
				return 1
			}
			rs++
		}
	}
	return rs
}


func (l ErrList) Stack() StackTrace {
	for _, er := range l {
		if er != nil {
			st := getStackTrace(er)
			if st != nil {
				return st
			}
		}
	}
	return nil
}


func (l ErrList) ToError() error {
	switch _errorsCount(false, l) {
	case 0:
		return nil
	case 1:
		return l.GetFirst()
	default:
		return ErrGroup(l)
	}
}


func _errorsCount(exitOnAny bool, els []error) int {
	rs := 0
	for _, er := range els {
		if er != nil {
			rs++
			if exitOnAny {
				break
			}
		}
	}
	return rs
}

/*
   ::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::

   I HAVE NO DESIRE TO WALK ON WATER," SAID SIDDHARTA.
   "LET THE OLD SHRAMANAS SATISFY THEMSELVES WITH SUCH SKILLS.

   SIDDHARTA
   - HERMANN HESSE -

   :::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::

*/