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

#define PORT 7300
#define BUFFER_SIZE 1024

void serve_file(int new_socket, char *filename) {
    int fd;
    ssize_t bytes_read;
    char file_buffer[BUFFER_SIZE];

    fd = open(filename, O_RDONLY);
    if (fd == -1) {
        perror("Error opening file");
        return;
    }

    while ((bytes_read = read(fd, file_buffer, BUFFER_SIZE)) > 0) {
        write(new_socket, file_buffer, bytes_read);
    }

    close(fd);
}

int main(int argc, char *argv[]) {
    int server_fd, new_socket;
    struct sockaddr_in address;
    int opt = 1;
    int addrlen = sizeof(address);
    char buffer[BUFFER_SIZE] = {0};
    char *hello = "HTTP/1.1 200 OK\nContent-Type: application/pdf\r\n\r\n";

    // Creating socket file descriptor
    if ((server_fd = socket(AF_INET, SOCK_STREAM, 0)) == 0) {
        perror("socket failed");
        exit(EXIT_FAILURE);
    }

    // Forcefully attaching socket to the port 8080

    address.sin_family = AF_INET;
    address.sin_addr.s_addr = INADDR_ANY;
    address.sin_port = htons(PORT);

    // Forcefully attaching socket to the port 8080
    if (bind(server_fd, (struct sockaddr *)&address, sizeof(address))<0) {
        perror("bind failed");
        exit(EXIT_FAILURE);
    }

    if (listen(server_fd, 3) < 0) {
        perror("listen");
        exit(EXIT_FAILURE);
    }

    while (1) {
        printf("\n+++++++ Waiting for new connection ++++++++\n\n");
        if ((new_socket = accept(server_fd, (struct sockaddr *)&address, (socklen_t*)&addrlen))<0) {
            perror("accept");
            exit(EXIT_FAILURE);
        }

        read(new_socket, buffer, BUFFER_SIZE);
        printf("%s\n", buffer);

        // Here you need to parse the request and extract the filename.
        // For simplicity, we're always serving the same file.
        char *filename = argv[1];

        write(new_socket, hello, strlen(hello));
        serve_file(new_socket, filename);

        printf("File served successfully\n");
        close(new_socket);
    }

    return 0;
}