// Author: Matthew Shiel
package main

import (
	"embed"
	"encoding/json"
	"fmt"
	"html/template"
	"io/ioutil"
	"log"
	"net/http"
	"strings"

	"git.riomhaire.com/gremlin/elizaservice/eliza"
	"github.com/jaffee/commandeer"
	"github.com/labstack/echo/v4"
	"github.com/labstack/echo/v4/middleware"
)

//go:embed web/*
var web embed.FS

//go:embed templates/*
var templates embed.FS

//go:embed bots/*
var bots embed.FS

type Main struct {
	BotName string `help:"What This Bot is Called."`
	Port    int    `help:"What port bot is listening too"`
}

func NewMain() *Main {
	return &Main{
		BotName: "Eliza",
		Port:    8070,
	}
}

func findPersonality(name string) (personality eliza.Personality, err error) {
	filename := "bots/" + name + ".json"
	jsonFile, err := bots.Open(filename)
	// if we os.Open returns an error then handle it
	if err != nil {
		return
	}
	//	fmt.Println("Successfully Opened ", filename)
	byteValue, _ := ioutil.ReadAll(jsonFile)

	// we initialize our Users array
	personality = eliza.Personality{}

	// we unmarshal our byteArray which contains our
	// jsonFile's content into 'users' which we defined above
	json.Unmarshal(byteValue, &personality)

	// defer the closing of our jsonFile so that we can parse it later on
	defer jsonFile.Close()

	return
}

func chantboInteractiontEndpoint(c echo.Context) error {
	// Extract question from GET request
	question := c.QueryParam("value")
	botname := c.QueryParam("bot")

	// default to eliza
	if len(botname) == 0 {
		botname = "eliza"
	}

	personality, err := findPersonality(strings.ToLower(botname)) // files are in lowercase
	if err != nil {
		fmt.Fprintf(c.Response(), "%s", err.Error())
		return nil
	}

	// Return Eliza's response's so long as the user doesn't give a quit statement
	character := eliza.NewBotPersonality(&personality)
	answer := character.ReplyTo(question)

	// Return Eliza's answer
	fmt.Fprintf(c.Response(), "%s", answer)
	return nil
}

func chantbotEndpoint(c echo.Context) error {
	c.Response().WriteHeader(http.StatusOK)
	c.Response().Header().Add("Content-Type", "text/html")

	// Note the call to ParseFS instead of Parse
	personality := c.Param("personality")
	t, err := template.ParseFS(templates, fmt.Sprintf("templates/%s.html", personality))
	if err != nil {
		log.Fatal(err)
	}
	// respond with the output of template execution
	t.Execute(c.Response(), struct {
		Id         string
		GivenName  string
		FamilyName string
		Name       string
		Bot        string
	}{
		Id:         c.QueryParam("user_id"),
		GivenName:  c.QueryParam("given_name"),
		FamilyName: c.QueryParam("family_name"),
		Name:       c.QueryParam("name"),
		Bot:        strings.Title(strings.ToLower(personality)),
	})
	return nil
}

func (m *Main) Run() error {

	fmt.Println(`
####### #         ###   #######    #
#       #          #         #    # #
#       #          #        #    #   #
#####   #          #       #    #     #
#       #          #      #     #######
#       #          #     #      #     #
####### #######   ###   ####### #     #
	`)
	fmt.Println()

	e := echo.New()

	var contentHandler = echo.WrapHandler(http.FileServer(http.FS(web)))
	var contentRewrite = middleware.Rewrite(map[string]string{"/*": "/web/$1"})

	e.GET("/user-input", chantboInteractiontEndpoint)
	e.GET("/chatbot/:personality", chantbotEndpoint)
	e.GET("/*", contentHandler, contentRewrite)
	e.Logger.Fatal(e.Start(fmt.Sprintf(":%d", m.Port)))

	return nil
}

func main() {
	err := commandeer.Run(NewMain())
	if err != nil {
		fmt.Println(err)
	}
}