package main

import (
	_ "embed"
	"encoding/json"
	"fmt"
	"io/ioutil"
	"log"
	"net/http"
)

//go:embed public/index.html
var index string

type Server struct {
	ledger Ledger
	debug  bool
}

func (server Server) ServeHTTP(w http.ResponseWriter, r *http.Request) {
	log.Println(r.Method + r.URL.Path)
	switch r.Method + r.URL.Path {
	case "GET/api/transactions":
		server.getTransactions(w, r)
	case "PUT/api/transactions":
		server.putTransactions(w, r)
	case "GET/api/balances":
		server.getBalances(w, r)
	default:
		if server.debug {
			b, _ := ioutil.ReadFile("./public/index.html")
			w.Write(b)
		} else {
			fmt.Fprint(w, index)
		}
	}
}

func (server Server) err(w http.ResponseWriter, r *http.Request, err error) {
	log.Println(r.Method, r.URL.Path, err)
	http.Error(w, fmt.Sprint(err.Error()), http.StatusInternalServerError)
}

func (server Server) getTransactions(w http.ResponseWriter, r *http.Request) {
	transactions, err := server.ledger.Transactions()
	if err != nil {
		server.err(w, r, err)
		return
	}
	json.NewEncoder(w).Encode(map[string]interface{}{"Transactions": transactions})
}

func (server Server) putTransactions(w http.ResponseWriter, r *http.Request) {
	var request struct {
		IDX int `json:"idx"`
		Transaction
	}
	if err := json.NewDecoder(r.Body).Decode(&request); err != nil {
		server.err(w, r, err)
		return
	}
	if err := server.ledger.SetTransaction(request.IDX, request.Transaction); err != nil {
		server.err(w, r, err)
		return
	}
	json.NewEncoder(w).Encode(map[string]interface{}{"ok": true})
}

func (server Server) getBalances(w http.ResponseWriter, r *http.Request) {
	balances, err := server.ledger.Balances()
	if err != nil {
		server.err(w, r, err)
		return
	}
	json.NewEncoder(w).Encode(map[string]interface{}{"Balances": balances})
}