package puller

import (
    "github.com/zelenin/go-tdlib/client"
)

func ChatHistory(tdlibClient *client.Client, chatId int64) (chan *client.Message, chan error) {
    messageChan := make(chan *client.Message, 10)
    errChan := make(chan error, 1)

    var fromMessageId int64 = 0
    var offset int32 = 0
    var limit int32 = 100

    go chatHistory(tdlibClient, messageChan, errChan, chatId, fromMessageId, offset, limit, false)

    return messageChan, errChan
}

func chatHistory(tdlibClient *client.Client, messageChan chan *client.Message, errChan chan error, chatId int64, fromMessageId int64, offset int32, limit int32, onlyLocal bool) {
    defer func() {
        close(messageChan)
        close(errChan)
    }()

    for {
        messages, err := tdlibClient.GetChatHistory(chatId, fromMessageId, offset, limit, onlyLocal)
        if err != nil {
            errChan <- err

            return
        }

        if len(messages.Messages) == 0 {
            errChan <- EOP

            break
        }

        for _, message := range messages.Messages {
            fromMessageId = message.Id

            messageChan <- message
        }
    }
}