// ------------------------------------------------------------------------
// 🚀 Project active3
// 🔗 Active Thing (activething.com) git.activething.com/go
//
//    File name  stringify.go
// ✍️ Created by DEV
// 📅 Modified   06/05/2024
//
// 🔒 Copyright 2024 activething.com
//  
// 📜 LICENSE --------------------------------------------------------------
// 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 erstr

import (
	"bytes"
	"fmt"
	"strings"
	"typs/strs"
)

type (

	StringifyError 	 struct {
		labelSep     string
		lineLabelFmt string
		lineErrorFmt string
		trans        strs.Transformers
	}

	StringifyErrorFnc func (stringify *StringifyError)
)



func NewStringifyError (options ...StringifyErrorFnc) *StringifyError {
	s := &StringifyError{
		labelSep:     labelSep,
		lineLabelFmt: "%s" + labelSep + "%s\n",
		lineErrorFmt: labelError + labelSep + "%s\n",
	}
	for _,o := range options {
		o(s)
	}
	return s
}


func (s *StringifyError) Stringify (text string, err error) string {
	ln := []string { "", text }
	var nl string
	ne := err
	for ne != nil {
		if st,is := ne.(stringer); is {
			nl = st.String()
		}
		if uw,is := ne.(unwrapper); is {
			ne = uw.Unwrap()
		} else {
			ne = nil
			if strings.Index(nl,labelError) != -1 {
				ln[0]= s.trans.Transform(nl)
				break
			}
		}
		ln = append(ln, s.trans.Transform(nl))
	}

	if len(ln[0]) == 0 {
		ln[0]=s.trans.Transform(err.Error())
	}
	if len(ln) == 0 {
		return ln[0]
	}
	b := bytes.Buffer{}
	for _,l := range ln {
		b.WriteString(l)
	}
	return b.String()
}

func (s *StringifyError) FormatLineError(strErr string) string {
	return fmt.Sprintf(s.lineErrorFmt,strErr) }

func (s *StringifyError) FormatLine (label, text string) string {
	return fmt.Sprintf(s.lineLabelFmt,label,text) }

func (s *StringifyError) removeLabel (text string) string {
	if strings.Index(text,s.labelSep) == -1 {
		return text
	}
	l := strings.Split(text,"\n")
	b := bytes.Buffer{}
	for _,t := range l {
		if p := strings.Index(t,s.labelSep); p != -1 {
			b.WriteString(t[p+len(s.labelSep):])
			b.WriteByte('\n')
		} else {
			b.WriteString(t)
		}
	}
	return b.String()
}





func WithFormats (fmtLabelLn, fmtErrorLn, sep string) StringifyErrorFnc {
	return func (s *StringifyError) {
		s.labelSep = sep
		s.lineLabelFmt = fmtLabelLn
		s.lineErrorFmt = fmtErrorLn
	}
}


func WithTransformers (add bool, transformers ...any) StringifyErrorFnc {
	return func (s *StringifyError) {
		if !add {
			s.trans = s.trans[:0]
		}
		for _, tf := range transformers {
			switch t:=tf.(type) {
			case string:
				if t == LabelRemover {
					s.trans = append(s.trans,strs.TransformFnc(s.removeLabel))
				} else {
					tr, hs := strs.G.Transformers.Get(t)
					if !hs {
						panic(strs.G.ErrTransformerNotFound)
					}
					s.trans = append(s.trans, tr)
				}
			case strs.Transformer:
				if t != nil {
					s.trans = append(s.trans,t)
				}
			case func(string)string:
				if t != nil {
					s.trans = append(s.trans,strs.TransformFnc(t))
				}
			default:
				panic(strs.G.ErrTransformerNotFound)
			}
		}
	}
}