//
// To Do
//    - Implement writer feature.
//    - Implement accepted location with number of times visited.
//          - Create a weight system to put it lower on the list if called.
//    - Create scoring mechanism to rate locations.
//    - Slack bot
//    - Voting option
//    - Yelp API integration for names and location.
//    - Open table API integration for reservations.
//    - Calender / scheduling integration.

package main
import (
    "bufio"
    "fmt"
    mathrand "math/rand"
    "os"
    "strings"
    "time"
    "net/http"
    "html/template"
    "log"
)

var lunchPAGE = "tpl/lunch.gtpl"
var lunchAddPAGE = "tpl/lunchadd.gtpl"
var lunchPlacePAGE = "tpl/lunchplaces.gtpl"
var lunchTimePAGE = "tpl/lunchtime.gtpl"

var locations []string
var previousPicks []string

func readLines() {
    file, err := os.Open("./places.txt")
    if err != nil {
        fmt.Println(err)
        os.Exit(1)
    }
    defer file.Close()
    scanner := bufio.NewScanner(file)
    for scanner.Scan() {
        s := strings.TrimRight(scanner.Text(), ",")
        locations = append(locations,s)
    }
    return
}

func random(min, max int) int {
    mathrand.Seed(time.Now().UnixNano())
    return mathrand.Intn(max - min) + min
}

func stringInSlice(a string) bool {
    for _, b := range previousPicks {
        if b == a {
            return true
        }
    }
    return false
}

func writeLocation(place string) bool {
    locations = append(locations,place)
    return true
}

func selector() string {
    maxLength := len(locations)
    rando := random(0,maxLength)
    pickedLocation := locations[rando]
    return pickedLocation
}

func isValidEntry(place string) bool{
    if place != ""{
        return true
    } else {
        return false
    }

}

func lunch(w http.ResponseWriter, r *http.Request) {
    tmpl := template.Must(template.ParseFiles(lunchPAGE))
    pickedLocation := selector()
    tmpl.Execute(w, pickedLocation)
}

func lunchTime(w http.ResponseWriter, r *http.Request) {
    tmpl := template.Must(template.ParseFiles(lunchTimePAGE))
    pickedLocation := selector()
    tmpl.Execute(w, pickedLocation)
}

func lunchAdd(w http.ResponseWriter, r *http.Request) {
    fmt.Println("method:", r.Method) //get method
    if r.Method == "GET" {
        t, _ := template.ParseFiles(lunchAddPAGE)
        t.Execute(w, nil)
    } else { //post method
        r.ParseForm()
        place := strings.Join(r.Form["place"], ",")
        if place != "" {
            fmt.Println("place added: ",place)
            writeLocation(place)
            t, _ := template.ParseFiles(lunchAddPAGE)
            t.Execute(w, nil)
        } else {
            fmt.Println("no value found, throwing away.")
            t, _ := template.ParseFiles(lunchAddPAGE)
            t.Execute(w, nil)
            list(w, nil)
        }
    }
}

func list(w http.ResponseWriter, r *http.Request) {
    tmpl := template.Must(template.ParseFiles(lunchPlacePAGE))
    tmpl.Execute(w,locations)
}

func test(w http.ResponseWriter, r *http.Request) {
    tmpl := template.Must(template.ParseFiles("static/test.html"))
    tmpl.Execute(w,locations)
}

func main() {
    readLines()
    http.HandleFunc("/lunch", lunch)             //web view
    http.HandleFunc("/lunchtime", lunchTime)     //curl view
    http.HandleFunc("/lunchadd", lunchAdd)
    http.HandleFunc("/lunchplaces", list)
    http.HandleFunc("/test", test)
    http.Handle("/", http.FileServer(http.Dir("static/")))
    log.Fatal(http.ListenAndServe(":8081", nil))
}