package slog

import (
	"encoding/json"
	"io"
	"os"
	"strings"
)

type LogWriter interface {
	WriteLog(msg string, kvs map[string]interface{})
}

func Printf(format string, args ...any) {
	formatLoc := format

	optNum := 0

	for bofs := strings.Index(formatLoc, "{{"); bofs != -1; bofs = strings.Index(formatLoc, "{{") {
		if optNum > len(args) {
			break
		}

		os.Stdout.Write([]byte(formatLoc[0:bofs]))

		formatLoc = formatLoc[bofs+2:]

		eofs := strings.Index(formatLoc, "}}")
		if eofs == -1 {
			break
		}

		b, _ := json.Marshal(args[optNum])

		os.Stdout.Write(b)

		optNum++

		formatLoc = formatLoc[eofs+2:]

	}
	os.Stdout.Write([]byte(formatLoc))
}

type Logger struct {
	w LogWriter
}

type KV struct {
	Key   string
	Value any
}

func (p *Logger) Printf(format string, args ...interface{}) {
	formatLoc := format
	optNum := 0

	kvs := make(map[string]interface{})
	for bofs := strings.Index(formatLoc, "{{"); bofs != -1; bofs = strings.Index(formatLoc, "{{") {
		if optNum > len(args) {
			break
		}

		formatLoc = formatLoc[bofs+2:]
		eofs := strings.Index(formatLoc, "}}")
		if eofs == -1 {
			break
		}

		key := formatLoc[0:eofs]

		kvs[key] = args[optNum]
		optNum++
		formatLoc = formatLoc[eofs+2:]
	}

	p.w.WriteLog(format, kvs)
}

func NewLogger(w LogWriter) *Logger {
	return &Logger{
		w: w,
	}
}

type JsonAdapter struct {
	w io.Writer
}

func NewJsonAdapter(w io.Writer) LogWriter {
	return &JsonAdapter{w: w}
}

func (j *JsonAdapter) WriteLog(msg string, kvs map[string]interface{}) {
	kvs["Log"] = msg
	b, _ := json.Marshal(kvs)
	j.w.Write(b)
}

type NullAdapter struct {
	w io.Writer
}

func NewNullAdapter() LogWriter {
	return &NullAdapter{}
}

func (j *NullAdapter) WriteLog(msg string, kvs map[string]interface{}) {
}