package main

import "github.com/jkrovnl/golearn2/app"

func main() {
    app.StartApp()
}
// ====================================== // app/app.go
package app

import (
    "net/http"

    "github.com/jkrovnl/golearn2/controllers"
)

func StartApp() {
    http.HandleFunc("/users", controllers.GetUser)
    if err := http.ListenAndServe(":8080", nil); err != nil {
        panic(err)
    }
}
// ====================================== // controllers/user_controllers.go
package controllers

import (
    "encoding/json"
    "net/http"
    "strconv"

    "github.com/jkrovnl/golearn2/utils"

    "github.com/jkrovnl/golearn2/services"
)

func GetUser(w http.ResponseWriter, req *http.Request) {
    userId, err := strconv.ParseInt(req.URL.Query().Get("user_id"), 10, 64)
    if err != nil {
        apiErr := &utils.ApplicationError{
            Message:    "user_id must be a number",
            StatusCode: http.StatusBadRequest,
            Code:       "bad_request",
        }
        jsonValue, _ := json.Marshal(apiErr)
        w.WriteHeader(apiErr.StatusCode)
        w.Write(jsonValue)
        return
    }
    user, apiErr := services.GetUser(userId)
    if apiErr != nil {
        jsonValue, _ := json.Marshal(apiErr)
        w.WriteHeader(apiErr.StatusCode)
        w.Write([]byte(jsonValue))
        return
    }
    jsonValue, _ := json.Marshal(user)
    w.Write(jsonValue)
}
// ====================================== // services/user_services.go
package services

import (
    "github.com/jkrovnl/golearn2/domain"
    "github.com/jkrovnl/golearn2/utils"
)

func GetUser(userId int64) (*domain.User, *utils.ApplicationError) {
    return domain.GetUser(userId)
}
// ====================================== // domain/user.go
package domain

type User struct {
    Id    int64  `json:"id"`
    Fname string `json:"fname"`
    Lname string `json:"lname"`
    Email string `json:"email"`
}
// ====================================== // domain/user_dao.go
package domain

import (
    "fmt"

    "github.com/jkrovnl/golearn2/utils"
)

var (
    users = map[int64]*User{
        123: {Id: 321, Fname: "Janis", Lname: "Lange", Email: "[email protected]"},
    }
)

func GetUser(userId int64) (*User, *utils.ApplicationError) { //(User, int, string, error) error was be last
    if user := users[userId]; user != nil {
        return user, nil
    }
    //fmt.Println(user) nebus jo user nav deklarets
    //return nil, errors.New(fmt.Sprintf("user %v was not found", userId)) //Ja return User nav ar * tad nevar return but nil
    return nil, &utils.ApplicationError{
        Message:    fmt.Sprintf("user %v was not found", userId),
        StatusCode: 404,
        Code:       "not_found",
    }
}
// ====================================== // utils/error_utils.go
package utils

type ApplicationError struct {
    Message    string `json:"message"`
    StatusCode int    `json:"status"`
    Code       string `json:"code"`
}