// Copyright (C) 2022-2023  Luke Shumaker <lukeshu@lukeshu.com>
//
// SPDX-License-Identifier: GPL-2.0-or-later

package json

import (
	"bytes"
	"encoding/json"
	"io"
	_ "unsafe"

	"git.lukeshu.com/go/lowmemjson"
	"git.lukeshu.com/go/lowmemjson/internal/fastio"
	"git.lukeshu.com/go/lowmemjson/internal/jsonparse"
	"git.lukeshu.com/go/lowmemjson/internal/jsonstruct"
)

var (
	parseTag         = jsonstruct.ParseTag
	clearCache       = jsonstruct.ClearCache
	cachedTypeFields = jsonstruct.IndexStruct
)

type scanner = lowmemjson.ReEncoderConfig

func checkValid(in []byte, scan *lowmemjson.ReEncoderConfig) error {
	return reencode(io.Discard, in, *scan)
}

func isValidNumber(s string) bool {
	var parser jsonparse.Parser
	for _, r := range s {
		if t, _ := parser.HandleRune(r); !t.IsNumber() {
			return false
		}
	}
	if t, _ := parser.HandleEOF(); t == jsonparse.RuneTypeError {
		return false
	}
	return true
}

const (
	startDetectingCyclesAfter = 1000
)

func isSpace(c byte) bool {
	switch c {
	case 0x0020, 0x000A, 0x000D, 0x0009:
		return true
	default:
		return false
	}
}

type encodeState struct {
	bytes.Buffer
}

//go:linkname encodeStringFromString git.lukeshu.com/go/lowmemjson.encodeStringFromString
func encodeStringFromString(w fastio.AllWriter, escaper lowmemjson.BackslashEscaper, str string) error

//go:linkname encodeStringFromBytes git.lukeshu.com/go/lowmemjson.encodeStringFromBytes
func encodeStringFromBytes(w fastio.AllWriter, escaper lowmemjson.BackslashEscaper, str []byte) error

func (es *encodeState) string(str string, _ bool) {
	if err := encodeStringFromString(&es.Buffer, nil, str); err != nil {
		panic(err)
	}
}

func (es *encodeState) stringBytes(str []byte, _ bool) {
	if err := encodeStringFromBytes(&es.Buffer, nil, str); err != nil {
		panic(err)
	}
}

type (
	Token = json.Token
	Delim = json.Delim
)

func (dec *Decoder) Token() (Token, error) {
	panic("not implemented")
}