#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <unistd.h>

#define BUFFER_SIZE 1024

void usage() {
    fprintf(stderr, "Usage: serveur port fichier\n");
    exit(1);
}

int main(int argc, char **argv) {
    if (argc != 3) {
        fprintf(stderr, "Erreur : Nombre incorrect d'arguments !\n");
        usage();
    }

    int port = atoi(argv[1]);

    int serverSocket = socket(AF_INET6, SOCK_STREAM, 0);
    if (serverSocket == -1) {
        perror("Error creating server socket");
        exit(EXIT_FAILURE);
    }

    struct sockaddr_in6 serverAddress;
    memset(&serverAddress, 0, sizeof(serverAddress));
    serverAddress.sin6_family = AF_INET6;
    serverAddress.sin6_addr = in6addr_any;
    serverAddress.sin6_port = htons(port);

    if (bind(serverSocket, (struct sockaddr *)&serverAddress, sizeof(serverAddress)) == -1) {
        perror("Error binding server socket");
        close(serverSocket);
        exit(EXIT_FAILURE);
    }

    if (listen(serverSocket, 1) == -1) {
        perror("Error listening on server socket");
        close(serverSocket);
        exit(EXIT_FAILURE);
    }

    printf("Server listening on port %d...\n", port);

    while (1) {
        int clientSocket = accept(serverSocket, NULL, NULL);
        if (clientSocket == -1) {
            perror("Error accepting client connection");
            close(serverSocket);
            exit(EXIT_FAILURE);
        }

        printf("Client connected. Transferring file...\n");

        FILE *file = fopen(argv[2], "rb");
        if (!file) {
            perror("Error opening file for reading");
            close(clientSocket);
            continue;  // Move on to the next client
        }

        // Send file content to client
        unsigned char buffer[BUFFER_SIZE];
        size_t bytesRead;
        while ((bytesRead = fread(buffer, 1, BUFFER_SIZE, file)) != 0) {
            if (send(clientSocket, buffer, bytesRead, 0) == -1) {
                perror("Error sending file content to client");
                fclose(file);
                close(clientSocket);
                continue;
            }
        }

        printf("File transfer complete.\n");

        fclose(file);
        close(clientSocket);
    }

    close(serverSocket);

    return 0;
}