// Copyright 2017 gf Author(https://github.com/gogf/gf). 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 gjson provides convenient API for JSON/XML/YAML/TOML data handling.
package gjson

import (
	"bytes"
	"encoding/json"
	"errors"
	"fmt"
	"github.com/gogf/gf/g/encoding/gtoml"
	"github.com/gogf/gf/g/encoding/gxml"
	"github.com/gogf/gf/g/encoding/gyaml"
	"github.com/gogf/gf/g/internal/rwmutex"
	"github.com/gogf/gf/g/os/gfcache"
	"github.com/gogf/gf/g/text/gregex"
	"github.com/gogf/gf/g/util/gconv"
	"reflect"
)

// New creates a Json object with any variable type of <data>,
// but <data> should be a map or slice for data access reason,
// or it will make no sense.
// The <unsafe> param specifies whether using this Json object
// in un-concurrent-safe context, which is false in default.
func New(data interface{}, unsafe ...bool) *Json {
	j := (*Json)(nil)
	switch data.(type) {
	case string, []byte:
		if r, err := LoadContent(gconv.Bytes(data)); err == nil {
			j = r
		} else {
			j = &Json{
				p:  &data,
				c:  byte(gDEFAULT_SPLIT_CHAR),
				vc: false,
			}
		}
	default:
		rv := reflect.ValueOf(data)
		kind := rv.Kind()
		if kind == reflect.Ptr {
			rv = rv.Elem()
			kind = rv.Kind()
		}
		switch kind {
		case reflect.Slice:
			fallthrough
		case reflect.Array:
			i := interface{}(nil)
			i = gconv.Interfaces(data)
			j = &Json{
				p:  &i,
				c:  byte(gDEFAULT_SPLIT_CHAR),
				vc: false,
			}
		case reflect.Map:
			fallthrough
		case reflect.Struct:
			i := interface{}(nil)
			i = gconv.Map(data, "json")
			j = &Json{
				p:  &i,
				c:  byte(gDEFAULT_SPLIT_CHAR),
				vc: false,
			}
		default:
			j = &Json{
				p:  &data,
				c:  byte(gDEFAULT_SPLIT_CHAR),
				vc: false,
			}
		}
	}
	j.mu = rwmutex.New(unsafe...)
	return j
}

// NewUnsafe creates a un-concurrent-safe Json object.
func NewUnsafe(data ...interface{}) *Json {
	if len(data) > 0 {
		return New(data[0], true)
	}
	return New(nil, true)
}

// Valid checks whether <data> is a valid JSON data type.
func Valid(data interface{}) bool {
	return json.Valid(gconv.Bytes(data))
}

// Encode encodes <value> to JSON data type of bytes.
func Encode(value interface{}) ([]byte, error) {
	return json.Marshal(value)
}

// Decode decodes <data>(string/[]byte) to golang variable.
func Decode(data interface{}) (interface{}, error) {
	var value interface{}
	if err := DecodeTo(gconv.Bytes(data), &value); err != nil {
		return nil, err
	} else {
		return value, nil
	}
}

// Decode decodes <data>(string/[]byte) to specified golang variable <v>.
// The <v> should be a pointer type.
func DecodeTo(data interface{}, v interface{}) error {
	decoder := json.NewDecoder(bytes.NewReader(gconv.Bytes(data)))
	decoder.UseNumber()
	return decoder.Decode(v)
}

// DecodeToJson codes <data>(string/[]byte) to a Json object.
func DecodeToJson(data interface{}, unsafe ...bool) (*Json, error) {
	if v, err := Decode(gconv.Bytes(data)); err != nil {
		return nil, err
	} else {
		return New(v, unsafe...), nil
	}
}

// Load loads content from specified file <path>,
// and creates a Json object from its content.
func Load(path string, unsafe ...bool) (*Json, error) {
	return LoadContent(gfcache.GetBinContents(path), unsafe...)
}

// LoadContent creates a Json object from given content,
// it checks the data type of <content> automatically,
// supporting JSON, XML, YAML and TOML types of data.
func LoadContent(data interface{}, unsafe ...bool) (*Json, error) {
	var err error
	var result interface{}
	b := gconv.Bytes(data)
	t := ""
	if len(b) == 0 {
		return New(nil, unsafe...), nil
	}
	// auto check data type
	if json.Valid(b) {
		t = "json"
	} else if gregex.IsMatch(`^<.+>[\S\s]+<.+>$`, b) {
		t = "xml"
	} else if gregex.IsMatch(`^[\s\t]*\w+\s*:\s*.+`, b) || gregex.IsMatch(`\n[\s\t]*\w+\s*:\s*.+`, b) {
		t = "yml"
	} else if gregex.IsMatch(`^[\s\t]*\w+\s*=\s*.+`, b) || gregex.IsMatch(`\n[\s\t]*\w+\s*=\s*.+`, b) {
		t = "toml"
	} else {
		return nil, errors.New("unsupported data type")
	}
	// convert to json type data
	switch t {
	case "json", ".json":
		// ok
	case "xml", ".xml":
		// TODO UseNumber
		b, err = gxml.ToJson(b)

	case "yml", "yaml", ".yml", ".yaml":
		// TODO UseNumber
		b, err = gyaml.ToJson(b)

	case "toml", ".toml":
		// TODO UseNumber
		b, err = gtoml.ToJson(b)

	default:
		err = errors.New("nonsupport type " + t)
	}
	if err != nil {
		return nil, err
	}
	if result == nil {
		decoder := json.NewDecoder(bytes.NewReader(b))
		decoder.UseNumber()
		if err := decoder.Decode(&result); err != nil {
			return nil, err
		}
		switch result.(type) {
		case string, []byte:
			return nil, fmt.Errorf(`json decoding failed for content: %s`, string(b))
		}
	}
	return New(result, unsafe...), nil
}