package main

import (
	"encoding/json"
	"fmt"
	"io"
	"local/args"
	"local/logb"
	"local/storage"
	"net/http"
)

type server struct {
	db storage.DBStream
}

func main() {
	as := args.NewArgSet()
	as.Append(args.INT, "p", "port", 8121)
	as.Append(args.STRING, "db", "db type", "mapstream")
	as.Append(args.STRING, "dbaddr", "db addr", "/tmp/db")
	if err := as.Parse(); err != nil {
		panic(err)
	}

	db, err := storage.New(storage.TypeFromString(as.GetString("db")), as.GetString("dbaddr"))
	if err != nil {
		panic(err)
	}
	dbs := db.(storage.DBStream)

	server := server{
		db: dbs,
	}
	addr := fmt.Sprintf(":%d", as.GetInt("p"))

	logb.Infof("listening: %s with %+v", addr, server)
	if err := http.ListenAndServe(addr, server); err != nil {
		panic(err)
	}
}

func (server server) ServeHTTP(w http.ResponseWriter, r *http.Request) {
	fileServer := http.FileServer(http.Dir("./"))
	switch r.URL.Path {
	case "/api":
		if err := server.apiHandler(w, r); err != nil {
			http.Error(w, err.Error(), http.StatusInternalServerError)
		}
	default:
		fileServer.ServeHTTP(w, r)
	}
}

func (server server) apiHandler(w http.ResponseWriter, r *http.Request) error {
	key := r.URL.Query().Get("key")
	switch r.Method {
	case http.MethodGet:
		switch key {
		case "":
			db := server.db.(storage.DB)
			keys, err := db.List(nil)
			if err != nil {
				return err
			}
			return json.NewEncoder(w).Encode(keys)
		default:
			v, err := server.db.GetStream(key)
			if err == storage.ErrNotFound {
				return nil
			}
			if err != nil {
				return err
			}
			_, err = io.Copy(w, v)
			return err
		}
	case http.MethodPost:
		return server.db.SetStream(key, r.Body)
	case http.MethodDelete:
		return server.db.SetStream(key, nil)
	default:
		http.NotFound(w, r)
	}
	return nil
}