package jessy

import (
	"encoding/json"
	"io"

	"github.com/avpetkun/jessy-go/std"
)

// Valid reports whether data is a valid JSON encoding.
func Valid(data []byte) bool {
	return std.Valid(data)
}

type Decoder = json.Decoder

// NewDecoder returns a new decoder that reads from r.
//
// The decoder introduces its own buffering and may
// read data from r beyond the JSON values requested.
func NewDecoder(r io.Reader) *Decoder {
	return json.NewDecoder(r)
}

// Unmarshal parses the JSON-encoded data and stores the result
// in the value pointed to by v. If v is nil or not a pointer,
// Unmarshal returns an [InvalidUnmarshalError].
//
// Unmarshal uses the inverse of the encodings that
// [Marshal] uses, allocating maps, slices, and pointers as necessary,
// with the following additional rules:
//
// To unmarshal JSON into a pointer, Unmarshal first handles the case of
// the JSON being the JSON literal null. In that case, Unmarshal sets
// the pointer to nil. Otherwise, Unmarshal unmarshals the JSON into
// the value pointed at by the pointer. If the pointer is nil, Unmarshal
// allocates a new value for it to point to.
//
// To unmarshal JSON into a value implementing [Unmarshaler],
// Unmarshal calls that value's [Unmarshaler.UnmarshalJSON] method, including
// when the input is a JSON null.
// Otherwise, if the value implements [encoding.TextUnmarshaler]
// and the input is a JSON quoted string, Unmarshal calls
// [encoding.TextUnmarshaler.UnmarshalText] with the unquoted form of the string.
//
// To unmarshal JSON into a struct, Unmarshal matches incoming object
// keys to the keys used by [Marshal] (either the struct field name or its tag),
// preferring an exact match but also accepting a case-insensitive match. By
// default, object keys which don't have a corresponding struct field are
// ignored (see [Decoder.DisallowUnknownFields] for an alternative).
//
// To unmarshal JSON into an interface value,
// Unmarshal stores one of these in the interface value:
//
//   - bool, for JSON booleans
//   - float64, for JSON numbers
//   - string, for JSON strings
//   - []interface{}, for JSON arrays
//   - map[string]interface{}, for JSON objects
//   - nil for JSON null
//
// To unmarshal a JSON array into a slice, Unmarshal resets the slice length
// to zero and then appends each element to the slice.
// As a special case, to unmarshal an empty JSON array into a slice,
// Unmarshal replaces the slice with a new empty slice.
//
// To unmarshal a JSON array into a Go array, Unmarshal decodes
// JSON array elements into corresponding Go array elements.
// If the Go array is smaller than the JSON array,
// the additional JSON array elements are discarded.
// If the JSON array is smaller than the Go array,
// the additional Go array elements are set to zero values.
//
// To unmarshal a JSON object into a map, Unmarshal first establishes a map to
// use. If the map is nil, Unmarshal allocates a new map. Otherwise Unmarshal
// reuses the existing map, keeping existing entries. Unmarshal then stores
// key-value pairs from the JSON object into the map. The map's key type must
// either be any string type, an integer, or implement [encoding.TextUnmarshaler].
//
// If the JSON-encoded data contain a syntax error, Unmarshal returns a [SyntaxError].
//
// If a JSON value is not appropriate for a given target type,
// or if a JSON number overflows the target type, Unmarshal
// skips that field and completes the unmarshaling as best it can.
// If no more serious errors are encountered, Unmarshal returns
// an [UnmarshalTypeError] describing the earliest such error. In any
// case, it's not guaranteed that all the remaining fields following
// the problematic one will be unmarshaled into the target object.
//
// The JSON null value unmarshals into an interface, map, pointer, or slice
// by setting that Go value to nil. Because null is often used in JSON to mean
// “not present,” unmarshaling a JSON null into any other Go type has no effect
// on the value and produces no error.
//
// When unmarshaling quoted strings, invalid UTF-8 or
// invalid UTF-16 surrogate pairs are not treated as an error.
// Instead, they are replaced by the Unicode replacement
// character U+FFFD.
func Unmarshal(data []byte, v any) error {
	return std.Unmarshal(data, v)
}

// Unmarshal without checks
func UnmarshalTrusted(data []byte, v any) error {
	return std.UnmarshalTrusted(data, v)
}
