ifm-telegram-bot/src/main/java/com/ifm/telegram/MessagePrinterBot.java

package com.ifm.telegram;

import com.google.gson.Gson;
import com.google.gson.GsonBuilder;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.telegram.telegrambots.bots.TelegramLongPollingBot;
import org.telegram.telegrambots.meta.api.methods.GetFile;
import org.telegram.telegrambots.meta.api.methods.send.SendPhoto;
import org.telegram.telegrambots.meta.api.objects.File;
import org.telegram.telegrambots.meta.api.objects.InputFile;
import org.telegram.telegrambots.meta.api.objects.Message;
import org.telegram.telegrambots.meta.api.objects.PhotoSize;
import org.telegram.telegrambots.meta.api.objects.Update;

import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.Paths;
import java.util.Comparator;
import java.util.List;
import java.util.Random;

/**
 * Simple Telegram bot that prints all received updates to console.
 * Useful for analyzing message structure from Telegram.
 */
public class MessagePrinterBot extends TelegramLongPollingBot {

    private static final Logger logger = LoggerFactory.getLogger(MessagePrinterBot.class);
    private static final Gson gson = new GsonBuilder().setPrettyPrinting().serializeNulls().create();

    private static final String DOWNLOAD_DIR = "downloads";
    private static final Random random = new Random();

    private final String botUsername;

    public MessagePrinterBot(String botToken, String botUsername) {
        super(botToken);
        this.botUsername = botUsername;
        // Ensure download directory exists
        try {
            Files.createDirectories(Paths.get(DOWNLOAD_DIR));
        } catch (Exception e) {
            logger.warn("Could not create download directory: {}", e.getMessage());
        }
    }

    @Override
    public String getBotUsername() {
        return botUsername;
    }

    @Override
    public void onUpdateReceived(Update update) {
        // Print full Update JSON
        System.out.println("========== UPDATE RECEIVED ==========");
        System.out.println(gson.toJson(update));
        System.out.println("======================================");

        // Print human-readable summary
        if (update.hasMessage()) {
            Message msg = update.getMessage();
            printMessageSummary(msg);

            // If text is "image", send a random photo from downloads
            if (msg.hasText() && msg.getText().trim().equalsIgnoreCase("image")) {
                sendRandomPhoto(msg.getChatId().toString());
            }
        } else if (update.hasEditedMessage()) {
            System.out.println("[EDITED MESSAGE]");
            printMessageSummary(update.getEditedMessage());
        } else if (update.hasCallbackQuery()) {
            System.out.println("[CALLBACK QUERY] data=" + update.getCallbackQuery().getData()
                    + " from=" + update.getCallbackQuery().getFrom().getUserName());
        } else if (update.hasChannelPost()) {
            System.out.println("[CHANNEL POST]");
            printMessageSummary(update.getChannelPost());
        } else {
            System.out.println("[OTHER UPDATE TYPE] updateId=" + update.getUpdateId());
        }

        System.out.println();
    }

    private void printMessageSummary(Message msg) {
        StringBuilder sb = new StringBuilder();
        sb.append("[MESSAGE SUMMARY]\n");
        sb.append("  chatId:    ").append(msg.getChatId()).append("\n");
        sb.append("  chatType:  ").append(msg.getChat().getType()).append("\n");
        sb.append("  messageId: ").append(msg.getMessageId()).append("\n");
        sb.append("  from:      ").append(msg.getFrom() != null ? msg.getFrom().getUserName() : "null").append("\n");
        sb.append("  firstName: ").append(msg.getFrom() != null ? msg.getFrom().getFirstName() : "null").append("\n");
        sb.append("  date:      ").append(msg.getDate()).append("\n");

        // Text
        if (msg.hasText()) {
            sb.append("  text:      ").append(msg.getText()).append("\n");
        }

        // Photo
        if (msg.hasPhoto()) {
            List<PhotoSize> photos = msg.getPhoto();
            sb.append("  photo:     ").append(photos.size()).append(" sizes\n");
            PhotoSize largest = photos.stream()
                    .max(Comparator.comparingInt(PhotoSize::getFileSize))
                    .orElse(null);
            if (largest != null) {
                sb.append("    largest: fileId=").append(largest.getFileId()).append("\n");
                sb.append("             size=").append(largest.getWidth()).append("x").append(largest.getHeight()).append("\n");
                sb.append("             fileSize=").append(largest.getFileSize()).append(" bytes\n");
            }
            if (msg.getCaption() != null) {
                sb.append("  caption:   ").append(msg.getCaption()).append("\n");
            }
            // Download the largest photo
            if (largest != null) {
                downloadPhoto(largest);
            }
        }

        // Document
        if (msg.hasDocument()) {
            sb.append("  document:  ").append(msg.getDocument().getFileName()).append("\n");
            sb.append("    mimeType: ").append(msg.getDocument().getMimeType()).append("\n");
            sb.append("    fileId:   ").append(msg.getDocument().getFileId()).append("\n");
            sb.append("    fileSize: ").append(msg.getDocument().getFileSize()).append(" bytes\n");
            if (msg.getCaption() != null) {
                sb.append("  caption:   ").append(msg.getCaption()).append("\n");
            }
        }

        // Voice
        if (msg.hasVoice()) {
            sb.append("  voice:     duration=").append(msg.getVoice().getDuration()).append("s\n");
            sb.append("    fileId:   ").append(msg.getVoice().getFileId()).append("\n");
        }

        // Video
        if (msg.hasVideo()) {
            sb.append("  video:     ").append(msg.getVideo().getDuration()).append("s\n");
            sb.append("    fileId:   ").append(msg.getVideo().getFileId()).append("\n");
        }

        // Sticker
        if (msg.hasSticker()) {
            sb.append("  sticker:   ").append(msg.getSticker().getEmoji()).append("\n");
            sb.append("    fileId:   ").append(msg.getSticker().getFileId()).append("\n");
        }

        // Location
        if (msg.hasLocation()) {
            sb.append("  location:  ").append(msg.getLocation().getLatitude())
                    .append(",").append(msg.getLocation().getLongitude()).append("\n");
        }

        // Contact
        if (msg.hasContact()) {
            sb.append("  contact:   ").append(msg.getContact().getFirstName())
                    .append(" ").append(msg.getContact().getPhoneNumber()).append("\n");
        }

        // Reply
        if (msg.getReplyToMessage() != null) {
            sb.append("  replyTo:   messageId=").append(msg.getReplyToMessage().getMessageId()).append("\n");
        }

        System.out.println(sb);
    }

    private void sendRandomPhoto(String chatId) {
        try {
            java.io.File dir = new java.io.File(DOWNLOAD_DIR);
            java.io.File[] images = dir.listFiles((d, name) ->
                    name.endsWith(".jpg") || name.endsWith(".jpeg") || name.endsWith(".png"));

            if (images == null || images.length == 0) {
                logger.info("No images in downloads/ to send");
                return;
            }

            java.io.File picked = images[random.nextInt(images.length)];
            SendPhoto sendPhoto = new SendPhoto();
            sendPhoto.setChatId(chatId);
            sendPhoto.setPhoto(new InputFile(picked));
            sendPhoto.setCaption("Random image: " + picked.getName());
            execute(sendPhoto);
            logger.info("Sent random photo: {} to chatId: {}", picked.getName(), chatId);
        } catch (Exception e) {
            logger.error("Failed to send random photo: {}", e.getMessage());
        }
    }

    private void downloadPhoto(PhotoSize photo) {
        try {
            GetFile getFile = new GetFile(photo.getFileId());
            File file = execute(getFile);
            String filePath = file.getFilePath();

            // Use fileId as filename, keep extension from Telegram's file_path
            String extension = "";
            if (filePath != null && filePath.contains(".")) {
                extension = filePath.substring(filePath.lastIndexOf("."));
            }
            String savedName = photo.getFileId() + extension;
            Path savePath = Paths.get(DOWNLOAD_DIR, savedName);

            java.io.File downloaded = downloadFile(file, savePath.toFile());
            logger.info("Photo saved: {} ({} bytes)", downloaded.getAbsolutePath(), downloaded.length());
        } catch (Exception e) {
            logger.error("Failed to download photo: {}", e.getMessage());
        }
    }
}