package main

import (
	"context"
	"time"

	"github.com/flosch/pongo2"
	"github.com/gofiber/fiber/v2"
	"github.com/gofiber/fiber/v2/middleware/logger"
	"github.com/gofiber/template/django/v3"
	"go.mongodb.org/mongo-driver/bson"
	"go.mongodb.org/mongo-driver/bson/primitive"
	"go.mongodb.org/mongo-driver/mongo"
	"go.mongodb.org/mongo-driver/mongo/options"
)

var mongoClient *mongo.Client
var userTmpl *pongo2.Template
var botTmpl *pongo2.Template

type Message struct {
	ID      primitive.ObjectID `bson:"_id"`
	Content string             `bson:"message"`
	Role    string             `bson:"role"`
	Date    time.Time          `bson:"date"`
}

type Conversation struct {
	ID       string
	Messages []Message
}

type User struct {
	ID         string `bson:"_id"`
	Username   string `bson:"username"`
	OAth2Token string `bson:"oauth2token"`
	IsSub      bool   `bson:"isSub"`
}

type CurrentSession struct {
	ID                    string
	CurrentConversationID string
	CurrentUserID         string
}

func connectToMongoDB(uri string) {
	serverAPI := options.ServerAPI(options.ServerAPIVersion1)
	opts := options.Client().ApplyURI(uri).SetServerAPIOptions(serverAPI)
	client, err := mongo.Connect(context.TODO(), opts)
	if err != nil {
		panic(err)
	}
	mongoClient = client

	if err := mongoClient.Ping(context.TODO(), nil); err != nil {
		panic(err)
	}
}

func main() {
	botTmpl = pongo2.Must(pongo2.FromFile("views/partials/message-bot.html"))
	userTmpl = pongo2.Must(pongo2.FromFile("views/partials/message-user.html"))

	// Import HTML using django engine/template
	engine := django.New("./views", ".html")

	if engine == nil {
		panic("Failed to create django engine")
	}

	// Create new Fiber instance. Can use any framework. I use fiber for speed and simplicity
	app := fiber.New(fiber.Config{
		Views:             engine,
		AppName:           "JADE 2.0",
		EnablePrintRoutes: true,
	})

	// Initialize
	go connectToMongoDB("mongodb://localhost:27017")

	// Add default logger
	app.Use(logger.New())

	// Add static files
	app.Static("/", "./static")

	// Add routes
	app.Get("/", indexHandler)
	app.Get("/isMongoDBConnected", isMongoDBConnectedHandler)

	app.Get("/chat", chatPageHandler)         // Complete chat page
	app.Put("/chat", addMessageHandler)       // Add message
	app.Delete("/chat", deleteMessageHandler) // Delete message
	app.Get("/loadChat", generateChatHTML)    // Load chat

	app.Get("/generateOpenai", addOpenaiMessage)

	app.Get("/test-button", testButtonHandler)

	// Start server
	app.Listen(":3000")
}

func indexHandler(c *fiber.Ctx) error {
	return c.Render("welcome", fiber.Map{}, "layouts/main")
}

func chatPageHandler(c *fiber.Ctx) error {
	return c.Render("chat", fiber.Map{
		"Messages": []Message{},
	}, "layouts/main")
}

func testButtonHandler(c *fiber.Ctx) error {
	return c.Render("partials/test-button", fiber.Map{})
}

func addMessageHandler(c *fiber.Ctx) error {
	message := c.FormValue("message")
	lastMessageAsked = message

	// Add bot message if there is no error
	userOut, err := userTmpl.Execute(pongo2.Context{"Content": message})
	if err != nil {
		panic(err)
	}

	botOut, err := botTmpl.Execute(pongo2.Context{"Content": "Waiting...", "IsPlaceholder": true})
	if err != nil {
		panic(err)
	}

	collection := mongoClient.Database("chat").Collection("messages")
	collection.InsertOne(context.Background(), bson.M{"message": message, "role": "user", "date": time.Now()})

	return c.SendString(userOut + botOut)
}

func deleteMessageHandler(c *fiber.Ctx) error {
	messageId := c.FormValue("messageId")

	// Convert the string ID to a MongoDB ObjectID
	objID, err := primitive.ObjectIDFromHex(messageId)
	if err != nil {
		// If the conversion fails, return an error response
		return c.Status(fiber.StatusBadRequest).JSON(fiber.Map{
			"error": "Invalid message ID format",
		})
	}

	// Delete messages in the database. This one and all the following ones
	collection := mongoClient.Database("chat").Collection("messages")

	// Get the date of the message
	var message Message
	err = collection.FindOne(context.TODO(), bson.M{"_id": objID}).Decode(&message)
	if err != nil {
		if err == mongo.ErrNoDocuments {
			return c.Status(fiber.StatusNotFound).JSON(fiber.Map{
				"error": "Message not found",
			})
		}
		return c.Status(fiber.StatusInternalServerError).JSON(fiber.Map{
			"error": "Failed to find message",
		})
	}

	// Delete the message and all messages with a date after the specified date
	filter := bson.M{
		"$or": []bson.M{
			{"_id": objID},
			{"date": bson.M{"$gt": message.Date}},
		},
	}
	_, err = collection.DeleteMany(context.TODO(), filter)
	if err != nil {
		return c.Status(fiber.StatusInternalServerError).JSON(fiber.Map{
			"error": "Failed to delete messages",
		})
	}

	return c.SendString("")
}

func generateChatHTML(c *fiber.Ctx) error {
	// Get the messages from the database
	collection := mongoClient.Database("chat").Collection("messages")

	// Get all messages
	cursor, err := collection.Find(context.TODO(), bson.D{})
	if err != nil {
		return c.Status(fiber.StatusInternalServerError).JSON(fiber.Map{
			"error": "Failed to find messages",
		})
	}

	// Convert the cursor to an array of messages
	var Messages []Message
	if err = cursor.All(context.TODO(), &Messages); err != nil {
		return c.Status(fiber.StatusInternalServerError).JSON(fiber.Map{
			"error": "Failed to convert cursor to array",
		})
	}

	htmlString := "<div class='columns is-centered'><div class='column is-half' id='chat-messages'>"

	for message := range Messages {
		if Messages[message].Role == "user" {
			userOut, err := userTmpl.Execute(pongo2.Context{"Content": Messages[message].Content})
			if err != nil {
				panic(err)
			}
			htmlString += userOut
		} else {
			botOut, err := botTmpl.Execute(pongo2.Context{"Content": Messages[message].Content})
			if err != nil {
				panic(err)
			}
			htmlString += botOut
		}
	}

	htmlString += "</div></div>"

	// Render the HTML template with the messages
	return c.SendString(htmlString)
}

func isMongoDBConnectedHandler(c *fiber.Ctx) error {
	if mongoClient != nil {
		return c.SendString("<h1>Connected</h1>")
	}
	return c.SendString("<h1 hx-get='/isMongoDBConnected' hx-trigger='every 1s' hx-swap='outerHTM'>Not connected</h1>")
}