2 files changed, 340 insertions, 0 deletions
diff --git a/liust-50/cmd/liustatus/status.go b/liust-50/cmd/liustatus/status.go
new file mode 100644
index 0000000..2c41e71
--- /dev/null
+++ b/liust-50/cmd/liustatus/status.go
@@ -0,0 +1,208 @@
+package main
+
+import (
+	"fmt"
+	"os"
+	"strings"
+	"time"
+
+	"janouch.name/desktop-tools/liust-50/charset"
+)
+
+// TODO(p): Make more elaberate animations with these.
+var kaomoji = []struct {
+	kao, message string
+}{
+	{"(o_o)", ""},
+	{"(ﾟﾛﾟ)", ""},
+	{"(ﾟ∩ﾟ)", ""},
+	{"(^_^)", ""},
+	{"  (^_^)", ""},
+	{"(^_^)  ", ""},
+	{"(x_x)", "ｽﾞｷｽﾞｷ"},
+	{"(T_T)", "ｽﾞｰﾝ"},
+	{"=^.^=", "ﾆｬｰ"},
+	{"(>_<)", "ｹﾞｯﾌﾟ"},
+	{"(O_O)", "ｼﾞｰ"},
+	{"(-_-)", ""},
+	{"(-_-)", "ｸﾞｰｸﾞｰ"},
+	{"(o_-)", ""},
+	{"(-_o)", ""},
+}
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+
+const (
+	displayWidth  = 20
+	displayHeight = 2
+	targetCharset = 0x63
+)
+
+type DisplayState struct {
+	Display [displayHeight][displayWidth]uint8
+}
+
+type Display struct {
+	Current, Last DisplayState
+}
+
+func NewDisplay() *Display {
+	t := &Display{}
+	for y := 0; y < displayHeight; y++ {
+		for x := 0; x < displayWidth; x++ {
+			t.Current.Display[y][x] = ' '
+			t.Last.Display[y][x] = ' '
+		}
+	}
+	return t
+}
+
+func (t *Display) SetLine(row int, content string) {
+	if row < 0 || row >= displayHeight {
+		return
+	}
+
+	runes := []rune(content)
+	for x := 0; x < displayWidth; x++ {
+		if x < len(runes) {
+			b, ok := charset.ResolveRune(runes[x], targetCharset)
+			if ok {
+				t.Current.Display[row][x] = b
+			} else {
+				t.Current.Display[row][x] = '?'
+			}
+		} else {
+			t.Current.Display[row][x] = ' '
+		}
+	}
+}
+
+func (t *Display) HasChanges() bool {
+	for y := 0; y < displayHeight; y++ {
+		for x := 0; x < displayWidth; x++ {
+			if t.Current.Display[y][x] != t.Last.Display[y][x] {
+				return true
+			}
+		}
+	}
+	return false
+}
+
+func (t *Display) Update() {
+	for y := 0; y < displayHeight; y++ {
+		x := 0
+		for x < displayWidth {
+			if t.Current.Display[y][x] == t.Last.Display[y][x] {
+				x++
+				continue
+			}
+
+			startX := x
+			var changes strings.Builder
+			for x < displayWidth &&
+				t.Current.Display[y][x] != t.Last.Display[y][x] {
+				changes.WriteByte(t.Current.Display[y][x])
+				t.Last.Display[y][x] = t.Current.Display[y][x]
+				x++
+			}
+
+			fmt.Printf("\x1b[%d;%dH%s", y+1, startX+1, changes.String())
+		}
+	}
+
+	os.Stdout.Sync()
+}
+
+func centerText(text string, width int) string {
+	textLen := len([]rune(text))
+	if textLen >= width {
+		return text[:width]
+	}
+	leftPad := (width - textLen + 1) / 2
+	rightPad := width - textLen - leftPad
+	return strings.Repeat(" ", leftPad) + text + strings.Repeat(" ", rightPad)
+}
+
+func kaomojiProducer(lines chan<- string) {
+	ticker := time.NewTicker(30_000 * time.Millisecond)
+	defer ticker.Stop()
+
+	idx := 0
+	for {
+		km := kaomoji[idx]
+
+		line := centerText(km.kao, displayWidth)
+		if km.message != "" {
+			line = line[:14] + km.message
+			line += strings.Repeat(" ", displayWidth-len([]rune(line)))
+		}
+
+		lines <- line
+
+		idx = (idx + 1) % len(kaomoji)
+		<-ticker.C
+	}
+}
+
+func statusProducer(lines chan<- string) {
+	ticker := time.NewTicker(1 * time.Second)
+	defer ticker.Stop()
+
+	temperature, fetcher := "", NewWeatherFetcher()
+	temperatureChan := make(chan string)
+	go fetcher.Run(5*time.Minute, temperatureChan)
+
+	for {
+		select {
+		case newTemperature := <-temperatureChan:
+			temperature = newTemperature
+		default:
+		}
+
+		now := time.Now()
+		status := fmt.Sprintf("%s %3s %s",
+			now.Format("Mon  2 Jan"), temperature, now.Format("15:04"))
+
+		// Ensure exactly 20 characters.
+		runes := []rune(status)
+		if len(runes) > displayWidth {
+			status = string(runes[:displayWidth])
+		} else if len(runes) < displayWidth {
+			status = status + strings.Repeat(" ", displayWidth-len(runes))
+		}
+
+		lines <- status
+		<-ticker.C
+	}
+}
+
+func main() {
+	terminal := NewDisplay()
+
+	kaomojiChan := make(chan string, 1)
+	statusChan := make(chan string, 1)
+
+	go kaomojiProducer(kaomojiChan)
+	go statusProducer(statusChan)
+
+	// TODO(p): And we might want to disable cursor visibility as well.
+	fmt.Printf("\x1bR%c", targetCharset)
+	fmt.Print("\x1b[2J") // Clear display
+
+	go func() {
+		kaomojiChan <- centerText(kaomoji[0].kao, displayWidth)
+		statusChan <- strings.Repeat(" ", displayWidth)
+	}()
+
+	for {
+		select {
+		case line := <-kaomojiChan:
+			terminal.SetLine(0, line)
+		case line := <-statusChan:
+			terminal.SetLine(1, line)
+		}
+		if terminal.HasChanges() {
+			terminal.Update()
+		}
+	}
+}
diff --git a/liust-50/cmd/liustatus/weather.go b/liust-50/cmd/liustatus/weather.go
new file mode 100644
index 0000000..c744f2f
--- /dev/null
+++ b/liust-50/cmd/liustatus/weather.go
@@ -0,0 +1,132 @@
+package main
+
+import (
+	"encoding/xml"
+	"fmt"
+	"io"
+	"log"
+	"net/http"
+	"strconv"
+	"time"
+)
+
+const (
+	baseURL   = "https://api.met.no/weatherapi"
+	userAgent = "liustatus/1.0"
+
+	// Prague coordinates.
+	lat      = 50.08804
+	lon      = 14.42076
+	altitude = 202
+)
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+
+type Weatherdata struct {
+	XMLName xml.Name `xml:"weatherdata"`
+	Product Product  `xml:"product"`
+}
+
+type Product struct {
+	Times []Time `xml:"time"`
+}
+
+type Time struct {
+	From     string   `xml:"from,attr"`
+	To       string   `xml:"to,attr"`
+	Location Location `xml:"location"`
+}
+
+type Location struct {
+	Temperature *Temperature `xml:"temperature"`
+}
+
+type Temperature struct {
+	Unit  string `xml:"unit,attr"`
+	Value string `xml:"value,attr"`
+}
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+
+// WeatherFetcher handles weather data retrieval.
+type WeatherFetcher struct {
+	client *http.Client
+}
+
+// NewWeatherFetcher creates a new weather fetcher instance.
+func NewWeatherFetcher() *WeatherFetcher {
+	return &WeatherFetcher{
+		client: &http.Client{Timeout: 30 * time.Second},
+	}
+}
+
+// fetchWeather retrieves the current temperature from the API.
+func (w *WeatherFetcher) fetchWeather() (string, error) {
+	url := fmt.Sprintf(
+		"%s/locationforecast/2.0/classic?lat=%.5f&lon=%.5f&altitude=%d",
+		baseURL, lat, lon, altitude)
+
+	req, err := http.NewRequest("GET", url, nil)
+	if err != nil {
+		return "", err
+	}
+
+	req.Header.Set("User-Agent", userAgent)
+
+	resp, err := w.client.Do(req)
+	if err != nil {
+		return "", err
+	}
+	defer resp.Body.Close()
+
+	if resp.StatusCode != http.StatusOK {
+		return "", fmt.Errorf("API returned status %d", resp.StatusCode)
+	}
+
+	body, err := io.ReadAll(resp.Body)
+	if err != nil {
+		return "", err
+	}
+
+	var weatherData Weatherdata
+	if err := xml.Unmarshal(body, &weatherData); err != nil {
+		return "", err
+	}
+
+	now := time.Now().UTC()
+	for _, t := range weatherData.Product.Times {
+		toTime, err := time.Parse("2006-01-02T15:04:05Z", t.To)
+		if err != nil || toTime.Before(now) {
+			continue
+		}
+		if t.Location.Temperature != nil {
+			temp, err := strconv.ParseFloat(t.Location.Temperature.Value, 64)
+			if err != nil {
+				continue
+			}
+			return fmt.Sprintf("%dﾟ", int(temp)), nil
+		}
+	}
+
+	return "", fmt.Errorf("no usable temperature data found")
+}
+
+// update fetches new weather data and returns it.
+func (w *WeatherFetcher) update() string {
+	temp, err := w.fetchWeather()
+	if err != nil {
+		log.Printf("Error fetching weather: %v", err)
+	}
+	return temp
+}
+
+// Run runs as a goroutine to periodically fetch weather data.
+func (w *WeatherFetcher) Run(interval time.Duration, output chan<- string) {
+	ticker := time.NewTicker(interval)
+	defer ticker.Stop()
+
+	output <- w.update()
+	for range ticker.C {
+		output <- w.update()
+	}
+}