package main

import (
	"encoding/json"
	"fmt"
	"log"
	"math"
	"time"

	"github.com/Arman92/go-tdlib"
)

func getHistory(c *tdlib.Client, chatID64 *int64) {
	var msgCount int32 = 0
	var msgParsed int32 = 0
	var loopOverflow int32 = 0
	var lastParsedID64 int64 = int64(math.MaxInt64)
	var lastParsedTime time.Time = time.Now()
	var chat int64
	var m ChatWarsMessage

	chat = *chatID64

	chatDetails, err := c.GetChat(chat)
	failOnError(err, "getHistory : GetChat")
	fmt.Printf("Exporting historic messages for chat %d (%s) ...\n", chat, chatDetails.Title)

	for lastParsedID64 >= 0 {
		prevLastParsedID64 := lastParsedID64
		msgs, err := c.GetChatHistory(chat, lastParsedID64, 0, 99, false)
		if err != nil {
			if err.Error() == "timeout" {
				logOnError(err, "Waiting....")
				fmt.Printf("Timeout  : %d messages retrieved out of %d dating back %s (%d) ...\n", msgCount, msgParsed, lastParsedTime.Format(time.RFC3339), lastParsedID64)
				time.Sleep(5 * time.Second)
			} else {
				logOnError(err, "Cannot get history")
				lastParsedID64 = -1
			}
		} else if msgs.TotalCount > 0 {
			for _, msg := range msgs.Messages {
				msgParsed = msgParsed + 1
				lastParsedTime = time.Unix(int64(msg.Date), 0)
				switch msg.Content.GetMessageContentEnum() {
				case tdlib.MessageTextType:
					if msg.ForwardInfo == nil {
						m = ChatWarsMessage{
							TGUserID64:       ownUserID64,
							TGSenderUserID64: int64(msg.SenderUserID),
							ID64:             msg.ID,
							ChatID64:         msg.ChatID,
							Text:             msg.Content.(*tdlib.MessageText).Text.Text,
						}
						m.Date = time.Unix(int64(msg.Date), 0)
					} else {
						if msg.ForwardInfo.GetMessageForwardInfoEnum() == tdlib.MessageForwardedFromUserType {
							m = ChatWarsMessage{
								TGUserID64:       int64(msg.SenderUserID),
								TGSenderUserID64: int64(msg.ForwardInfo.(*tdlib.MessageForwardedFromUser).SenderUserID),
								ID64:             msg.ID,
								ChatID64:         0,
								Text:             msg.Content.(*tdlib.MessageText).Text.Text,
							}
							m.Date = time.Unix(int64(msg.ForwardInfo.(*tdlib.MessageForwardedFromUser).Date), 0)

						} else {
							m = ChatWarsMessage{
								ID64: 0,
							}
						}
					}

					if m.ID64 != 0 {
						// export msg here
						msgCount = msgCount + 1
					}
				default:
					log.Printf("getHistory(%d) : no handler for %s\n", msg.ID, msg.Content.GetMessageContentEnum())
				}
				if m.ID64 < lastParsedID64 {
					lastParsedID64 = msg.ID
					lastParsedTime = m.Date
				}
				if msgParsed%1000 == 0 {
					fmt.Printf("Waiting  : %d messages retrieved out of %d dating back %s (%d) ...\n", msgCount, msgParsed, lastParsedTime.Format(time.RFC3339), lastParsedID64)
				}

			}
		} else {
			lastParsedID64 = -1
		}
		if prevLastParsedID64 == lastParsedID64 {
			loopOverflow++
			if loopOverflow == 5 {
				// we should be at the end !
				lastParsedID64 = -1
			} else {
				logOnError(err, "Overflow ...")
				fmt.Printf("Overflow : %d messages retrieved out of %d dating back %s (%d) ...\n", msgCount, msgParsed, lastParsedTime.Format(time.RFC3339), lastParsedID64)
				time.Sleep(5 * time.Second)
			}
		} else {
			loopOverflow = 0
		}
	}
	log.Printf("Exported %d messages.\n", msgCount)
	fmt.Printf("Exported %d messages.\n", msgCount)
}

func OwnUserID(c *tdlib.Client) int32 {
	user, _ := c.GetMe()
	return user.ID
}