package main

import (
	"bytes"
	"encoding/binary"
	"encoding/json"
	"image"
	"image/color"
	"image/png"
	"os"
)

type Config struct {
	Zodiac string `json:"zodiac"`
	City   string `json:"city"`
}

const defaultZodiac = "射手座"

var configPath string

func loadConfig() *Config {
	data, err := os.ReadFile(configPath)
	if err != nil {
		return &Config{Zodiac: defaultZodiac}
	}
	var cfg Config
	if json.Unmarshal(data, &cfg) != nil {
		return &Config{Zodiac: defaultZodiac}
	}
	if cfg.Zodiac == "" {
		cfg.Zodiac = defaultZodiac
	}
	return &cfg
}

func saveConfig(cfg *Config) error {
	data, _ := json.MarshalIndent(cfg, "", "  ")
	return os.WriteFile(configPath, data, 0644)
}

func generateIcon() []byte {
	img := image.NewRGBA(image.Rect(0, 0, 16, 16))
	c := color.RGBA{R: 88, G: 101, B: 242, A: 255}
	for y := 0; y < 16; y++ {
		for x := 0; x < 16; x++ {
			img.Set(x, y, c)
		}
	}
	var buf bytes.Buffer
	png.Encode(&buf, img)
	pngData := buf.Bytes()
	ico := make([]byte, 22+len(pngData))
	binary.LittleEndian.PutUint16(ico[0:], 0)
	binary.LittleEndian.PutUint16(ico[2:], 1)
	binary.LittleEndian.PutUint16(ico[4:], 1)
	ico[6], ico[7], ico[8], ico[9] = 16, 16, 0, 0
	binary.LittleEndian.PutUint16(ico[10:], 1)
	binary.LittleEndian.PutUint16(ico[12:], 32)
	binary.LittleEndian.PutUint32(ico[14:], uint32(len(pngData)))
	binary.LittleEndian.PutUint32(ico[18:], 22)
	copy(ico[22:], pngData)
	return ico
}