libgpiod support and better docs

.gitignore

@@ -0,0 +1 @@
+.notes

README.md

@@ -0,0 +1,10 @@
+# WoLBodge
+
+## Configuration
+Configuration is done using environment variables.
+- `WOLBODGE_ADDRESS`: The address that WoLBodge should listen on, defaults to `:3000`.
+- `WOLBODGE_STORAGE_TYPE`: Storage type to pick, defaults to `ram`.
+  - `ram`: Sessions are stored in RAM.
+- `WOLBODGE_DEVICE_TYPE`: Device type to pick, defaults to `test`-
+  - `test`: A dummy device, used for testing.
+  - `libgpiod`: Uses the libgpiod commands under the hood. The gpio chip is specified using `WOLBODGE_DEVICE_GPIOCHIP`, the power button pin using `WOLBODGE_DEVICE_POWER_BUTTON_PIN` and the power LED pin using `WOLBODGE_DEVICE_POWER_LED_PIN`.

devices/raspi-gpio.go

@@ -1,5 +1,99 @@
 package devices
 
-func NewRaspiGPIO() Device {
+import (
+	"fmt"
+	"os/exec"
+	"sync"
+	"time"
+)
+
+func NewLibgpiod(gpiochip string, powerButtonPin int, powerLEDPin int) Device {
+	device := &libgpiod{
+		gpiochip:       gpiochip,
+		powerButtonPin: powerButtonPin,
+		powerLEDPin:    powerLEDPin,
+		lock:           sync.Mutex{},
+	}
+
+	return device
+}
+
+type libgpiod struct {
+	gpiochip       string
+	powerButtonPin int
+	powerLEDPin    int
+	lock           sync.Mutex
+}
+
+func (d *libgpiod) Status() (bool, error) {
+	d.lock.Lock()
+	defer d.lock.Unlock()
+
+	status, err := d.read(d.powerLEDPin)
+	if err != nil {
+		return false, err
+	}
+
+	return status, nil
+}
+
+func (d *libgpiod) PushPowerButton() error {
+	d.lock.Lock()
+	defer d.lock.Unlock()
+
+	err := d.write(d.powerButtonPin, 1)
+	if err != nil {
+		return err
+	}
+
+	time.Sleep(2 * time.Second)
+
+	err = d.write(d.powerButtonPin, 0)
+	if err != nil {
+		return err
+	}
+
 	return nil
 }
+
+func (d *libgpiod) write(pin int, value int) error {
+	cmd := exec.Command(
+		"env", "sh", "-c",
+		fmt.Sprintf("gpioset %s %d=%d", d.gpiochip, pin, value),
+	)
+
+	outRaw, err := cmd.Output()
+	if err != nil {
+		return err
+	}
+
+	out := string(outRaw)
+	if out == "" {
+		return nil
+	}
+
+	return fmt.Errorf("unexpected command output: %s", err)
+}
+
+func (d *libgpiod) read(pin int) (bool, error) {
+	cmd := exec.Command(
+		"env", "sh", "-c",
+		fmt.Sprintf("gpioget --bias pull-down %s %d", d.gpiochip, pin),
+	)
+
+	outRaw, err := cmd.Output()
+	if err != nil {
+		return false, err
+	}
+
+	out := string(outRaw)
+
+	switch out {
+	case "0\n":
+		return false, nil
+	case "1\n":
+		return true, nil
+	default:
+		return false, fmt.Errorf("unexpected command output: %s", out)
+	}
+}

env.go

@@ -0,0 +1,77 @@
+package main
+
+import (
+	"fmt"
+	"log"
+	"os"
+	"strconv"
+
+	"git.1e99.eu/1e99/wolbodge/devices"
+	"git.1e99.eu/1e99/wolbodge/sessions"
+)
+
+func NewStorage() (sessions.Storage, error) {
+	var storageType string
+	Env("WOLBODGE_STORAGE_TYPE", &storageType, "mem")
+
+	switch storageType {
+	case "mem", "memory":
+		return sessions.NewMemStorage(), nil
+
+	default:
+		return nil, fmt.Errorf("unknown storage type: %s", storageType)
+	}
+}
+
+func NewDevice() (devices.Device, error) {
+	var deviceType string
+	Env("WOLBODGE_DEVICE_TYPE", &deviceType, "test")
+
+	switch deviceType {
+	case "test":
+		return devices.NewTest(false), nil
+
+	case "libgpiod":
+		var gpiochip string
+		var powerButtonPin int
+		var powerLEDPin int
+		Env("WOLBODGE_DEVICE_GPIOCHIP", &gpiochip, "gpiochip0")
+		Env("WOLBODGE_DEVICE_POWER_BUTTON_PIN", &powerButtonPin, "27")
+		Env("WOLBODGE_DEVICE_POWER_LED_PIN", &powerLEDPin, "17")
+
+		return devices.NewLibgpiod(gpiochip, powerButtonPin, powerLEDPin), nil
+
+	default:
+		return nil, fmt.Errorf("unknown device type: %s", deviceType)
+	}
+}
+
+func Env(name string, out any, def string) {
+	raw := os.Getenv(name)
+	if raw == "" {
+		raw = def
+		log.Printf("No \"%s\" provided, defaulting to \"%s\".", name, def)
+	}
+
+	switch value := out.(type) {
+	case *int:
+		i, err := strconv.ParseInt(raw, 10, 64)
+		if err != nil {
+			log.Printf("\"%s\" is not a number (\"%s\").", name, raw)
+			return
+		}
+
+		*value = int(i)
+
+	case *bool:
+		switch raw {
+		case "true", "TRUE", "1":
+			*value = true
+		case "false", "FALSE", "0":
+			*value = false
+		}
+
+	case *string:
+		*value = raw
+	}
+}

main.go

@@ -7,9 +7,7 @@ import (
 	"net/http"
 	"time"
 
-	"git.1e99.eu/1e99/wolbodge/devices"
 	"git.1e99.eu/1e99/wolbodge/routes"
-	"git.1e99.eu/1e99/wolbodge/sessions"
 
 	_ "embed"
 )
@@ -18,7 +16,8 @@ import (
 var embed string
 
 func Run() error {
-	address := ":3000"
+	var address string
+	Env("WOLBODGE_ADDRESS", &address, ":3000")
 
 	tmpl := template.New("")
 	_, err := tmpl.Parse(embed)
@@ -26,8 +25,16 @@ func Run() error {
 		return fmt.Errorf("failed to parse template: %w", err)
 	}
 
-	device := devices.NewTest(false)
-	storage := sessions.NewMemStorage()
+	device, err := NewDevice()
+	if err != nil {
+		return fmt.Errorf("failed to create new device: %w", err)
+	}
+
+	storage, err := NewStorage()
+	if err != nil {
+		return fmt.Errorf("failed to create new storage: %w", err)
+	}
+
 	logger := log.Default()
 	mux := http.NewServeMux()