package main

import (
	"bytes"
	"crypto/tls"
	"encoding/json"
	"flag"
	"io"
	"log"
	"net/http"
)

type switcher struct {
	Name  string `json:"name"`
	State bool   `json:"state"`
}

var (
	logger log.Logger = *log.Default()
)

func init() {
	logger.SetFlags(log.Llongfile | log.Ltime)
}

func patch_request(url string, cmd string) error {
	req, err := http.NewRequest(http.MethodPatch, url, bytes.NewReader([]byte(cmd)))
	if err != nil {
		return err
	}
	res, err := http.DefaultClient.Do(req)
	if err != nil {
		return err
	}
	logger.Printf("got response!\n")
	logger.Printf("status code: %d\n", res.StatusCode)
	return nil
}

func do_the_switch(sw switcher) {
	var url string
	var cmd string
	switch sw.Name {
	case "chicken":
		url = "http://barsch:8080/katara/chicken"
		if sw.State {
			cmd = "{\"value\":\"on\"}"
		} else {
			cmd = "{\"value\":\"off\"}"
		}
	case "bed":
		url = "http://barsch:8080/katara/bed"
		if sw.State {
			cmd = "{\"value\":\"on\"}"
		} else {
			cmd = "{\"value\":\"off\"}"
		}
	case "sauna":
		url = "http://barsch:8080/katara/sauna"
		if sw.State {
			cmd = "{\"value\":\"on\"}"
		} else {
			cmd = "{\"value\":\"off\"}"
		}
	case "nut":
		url = "https://perinode-ms26f.local/sample/gpio2"
		if sw.State {
			cmd = "{\"data\": true}"
		} else {
			cmd = "{\"data\": false}"
		}
	case "wood":
		url = "https://perinode-gzzx6.local/sample/gpio1"
		if sw.State {
			cmd = "{\"data\": true}"
		} else {
			cmd = "{\"data\": false}"
		}
	case "tomato":
		url = "https://perinode-jim7u.local/sample/gpio1"
		if sw.State {
			cmd = "{\"data\": true}"
		} else {
			cmd = "{\"data\": false}"
		}
	case "barn":
		url = "https://perinode-jim7u.local/sample/gpio1"
		if sw.State {
			cmd = "{\"data\": true}"
		} else {
			cmd = "{\"data\": false}"
		}
	default:
		logger.Printf("Unknown switch: %s", sw.Name)
		return
	}
	err := patch_request(url, cmd)
	if err != nil {
		logger.Print(err)
	}
}

func http_endpoint_water_switch(w http.ResponseWriter, r *http.Request) {
	w.Header().Set("Content-type", "application/json; charset=utf-8;")
	if r.Method == http.MethodPatch {
		tmp, err := io.ReadAll(r.Body)
		if err != nil {
			w.WriteHeader(http.StatusInternalServerError)
			w.Write(json.RawMessage(`{"error": "cannot unmarshal json to object"}`))
		} else {
			var sw switcher
			err = json.Unmarshal(tmp, &sw)
			if err != nil {
				w.WriteHeader(http.StatusInternalServerError)
				w.Write(json.RawMessage(`{"error": "cannot unmarshal json to object"}`))
			} else {
				do_the_switch(sw)
				w.WriteHeader(http.StatusAccepted)
			}
		}
	} else {
		w.WriteHeader(http.StatusMethodNotAllowed)
	}
}

func main() {
	logger.Println("starting")

	var webui_path string
	flag.StringVar(&webui_path, "w", "./webui", "Specify path to serve the web ui. Default is ./webui")
	flag.Parse()

	http.DefaultTransport.(*http.Transport).TLSClientConfig = &tls.Config{InsecureSkipVerify: true}
	// Serve files from static folder
	http.Handle("/", http.FileServer(http.Dir(webui_path)))

	http.HandleFunc("/water/switch", http_endpoint_water_switch)

	port := ":5005"
	logger.Println("Server is running on port" + port)

	// Start server on port specified above
	logger.Fatal(http.ListenAndServe(port, nil))

}