import java.util.ArrayList;
import java.util.List;

public class Main {
    public static void main(String[] args) {
        System.out.println("=== Simulated Download Manager ===");

        // 1. Read config
        DownloadConfig config;
        try {
            config = ConfigReader.readConfig("download_config.txt");
        } catch (Exception e) {
            System.out.println("Failed to read configuration: " + e.getMessage());
            return;
        }

        System.out.println("File name: " + config.getFileName());
        System.out.println("Total size (MB): " + config.getTotalSizeMB());
        System.out.println("Chunk count: " + config.getChunkCount());
        System.out.println();

        // 2. Create chunks
        List<ChunkStatus> chunks = ChunkUtils.createChunks(
                config.getTotalSizeMB(),
                config.getChunkCount()
        );

        // 3. Create worker threads
        List<Thread> workerThreads = new ArrayList<>();

        for (ChunkStatus chunk : chunks) {
            DownloadWorker worker = new DownloadWorker(chunk, config);
            Thread workerThread = new Thread(worker, "Worker-" + chunk.getChunkId());

            workerThreads.add(workerThread);

            System.out.println("Assigned Chunk #" + chunk.getChunkId()
                    + " (" + chunk.getChunkSizeMB() + " MB) to " + workerThread.getName());
        }


        ProgressMonitor monitor = new ProgressMonitor(config, chunks);
        Thread monitorThread = new Thread(monitor, "Progress-Monitor");


        monitorThread.start();


        for (Thread thread : workerThreads) {
            thread.start();
        }


        for (Thread thread : workerThreads) {
            try {
                thread.join();
            } catch (InterruptedException e) {
                System.out.println("Main thread interrupted while waiting for " + thread.getName());
                Thread.currentThread().interrupt();
            }
        }


        try {
            monitorThread.join();
        } catch (InterruptedException e) {
            System.out.println("Main thread interrupted while waiting for monitor.");
            Thread.currentThread().interrupt();
        }


        System.out.println();
        System.out.println("=== Final Report ===");

        int completedChunks = 0;
        double downloadedMB = 0.0;

        for (ChunkStatus chunk : chunks) {
            downloadedMB += chunk.getDownloadedMB();

            if (chunk.isCompleted()) {
                completedChunks++;
            }

            System.out.println(
                    "Chunk " + chunk.getChunkId()
                            + ": " + chunk.getDownloadedMB()
                            + "/" + chunk.getChunkSizeMB()
                            + " MB"
            );
        }

        System.out.println();
        System.out.println("Completed chunks: " + completedChunks + "/" + chunks.size());
        System.out.println("Downloaded total: " + downloadedMB + "/" + config.getTotalSizeMB() + " MB");
        System.out.println("Simulation finished.");
    }
}