import java.io.*;
import java.net.*;
import java.nio.file.Files;
import java.util.ArrayList;
import java.util.List;

public class ServerWeb {
    public static final String continutPath = "D:\\SCOALA\\PW\\Laborator6\\proiect1-IureaBogdan\\continut\\";
    public static int connectedUsers = 0;

    public static void main(String[] args) throws IOException {
        System.out.println("#########################################################################");
        System.out.println("Serverul asculta potentiali clienti.");
        // pornește un server pe portul 5678
        ServerSocket serverSocket = new ServerSocket(5678);
        while (true) {
            Socket clientSocket = serverSocket.accept();
            connectedUsers++;
            System.out.println("###CLIENT NOU###");
            // socketWriter - wrapper peste fluxul de ieșire folosit pentru a transmite date
            // clientului
            // PrintWriter socketWriter = new PrintWriter(clientSocket.getOutputStream(),
            // true);

            // socketReader - wrapper peste fluxul de intrare folosit pentru a primi date de
            // la client
            BufferedReader socketReader = new BufferedReader(new InputStreamReader(clientSocket.getInputStream()));
            // este citită prima linie de text din cerere
            String linieDeStart = socketReader.readLine();
            System.out.println("##### " + linieDeStart + " #####");
            // mesajul citit este transmis la client
            // interpretarea sirului de caractere `linieDeStart` pentru a extrage numele resursei cerut
            String requestedFile = StringRequestInterpretter(linieDeStart);
            boolean isFound = searchFile(requestedFile);

            // trimiterea răspunsului HTTP
            String path = continutPath + requestedFile;
            String contentType = "";
            switch (getFileType(linieDeStart)) {
                case 1:
                    contentType = "Content-Type:text/html; charset=UTF-8";
                    break;
                case 2:
                    contentType = "Content-Type:text/css";
                    break;
                case 3:
                    contentType = "Content-Type:application/js";
                    break;
                case 4:
                    contentType = "Content-Type:text/png";
                    break;
                case 5:
                    contentType = "Content-Type:text/jpeg";
                    break;
                case 6:
                    contentType = "Content-Type:text/gif";
                    break;
                case 7:
                    contentType = "Content-Type:image/x-icon";
                    break;
            }
            byte[] response = createResponse(isFound, path, contentType);
            clientSocket.getOutputStream().write(response);

            // închide conexiunea cu clientul
            // la apelul metodei close() se închid automat fluxurile de intrare și ieșire
            // (socketReader și socketWriter)

            clientSocket.close();

            //conditie pusa doar ca serverul sa dea eroare la 30 de cereri ca apoi sa se inchida
            if (connectedUsers > 30)
                serverSocket.close();
        }
    }

    private static String StringRequestInterpretter(String input) {
        int nrOfSl = 0;
        for (int i = 0; i < input.length(); i++) {
            if (input.charAt(i) == '/') {
                nrOfSl++;
            }
        }
        String temp = "";
        if (nrOfSl >= 2) {
            temp = input.substring(input.indexOf("/") + 1, input.indexOf("HTTP/") - 1);
        } else {
            temp = "index.html";
        }
        if (temp.contains("/")) {
            temp = temp.replace("/", "\\");
        }
        return temp;
    }

    private static int getFileType(String input) {
        int fileType = 0;
        if (input.contains(".html")) {
            fileType = 1;
        } else if (input.contains(".css")) {
            fileType = 2;
        } else if (input.contains(".js")) {
            fileType = 3;
        } else if (input.contains(".png")) {
            fileType = 4;
        } else if (input.contains(".jpg") || input.contains(".jpeg")) {
            fileType = 5;
        } else if (input.contains(".gif")) {
            fileType = 6;
        } else if (input.contains(".ico")) {
            fileType = 7;
        }
        return fileType;
    }

    private static boolean searchFile(String input) {
        File dir;
        int fileType = getFileType(input);
        File[] files;
        List<File> retFiles = new ArrayList<>();
        if (fileType == 1) {
            dir = new File(continutPath);
            files = dir.listFiles();
            for (File file : files) {
                if (file.getName().contains(".html")) {
                    retFiles.add(file);
                }
            }
        } else if (fileType == 2) {
            dir = new File(continutPath + "\\css\\");
            files = dir.listFiles();
            for (File file : files) {
                if (file.getName().contains(".css")) {
                    retFiles.add(file);
                }
            }
        } else if (fileType == 3) {
            dir = new File(continutPath + "\\js\\");
            files = dir.listFiles();
            for (File file : files) {
                if (file.getName().contains(".js")) {
                    retFiles.add(file);
                }
            }
        } else if (fileType == 4 || fileType == 5 || fileType == 6 || fileType == 7) {
            dir = new File(continutPath + "\\imagini\\");
            files = dir.listFiles();
            for (File file : files) {
                if (file.getName().contains(".jpeg") || file.getName().contains(".jpg")
                        || file.getName().contains(".gif") || file.getName().contains(".ico")
                        || file.getName().contains(".png")) {
                    retFiles.add(file);
                }
            }
        }
        boolean found = false;
        for (File file : retFiles) {
            if (!input.equals("index.html")) {
                String tempReqFile = input.substring(input.lastIndexOf('\\') + 1, input.length());
                if (file.getName().equals(tempReqFile)) found = true;
            }
            else found = true;
        }
        return found;
    }

    private static byte[] createResponse(boolean flag ,String path,String contentType) throws IOException
    {
        String response="", status="",length,type,server, CRLF,messageBody;
        int filetype=getFileType(path);
        if(filetype!=0)
        {
            byte[] imgFile=extractBytes(path);
            int messageLength=imgFile.length;
            status="HTTP:/1.1 200 OK\r\n";
            length="Content-Length:"+messageLength+"\r\n";
            type=contentType+"\r\n";
            server="Server:IBI\r\n";
            CRLF="\r\n";
            response=status+length+type+server+CRLF;
            byte[] byteReturn=new byte[response.getBytes().length+imgFile.length];
            System.arraycopy(response.getBytes(), 0, byteReturn, 0, response.getBytes().length);
            System.arraycopy(imgFile, 0, byteReturn, response.getBytes().length, imgFile.length);
            return byteReturn;
        }
        else
        {
            status="HTTP/1.1 404 Not Found\r\n";
            messageBody="<html><body><h1>Pagina ceruta nu exista sau este indisponibila!</h1></body></html>";
            length="Content-Length:"+messageBody.length()+"\r\n";
            type="Content-Type:text/html; charset=UTF-8\r\n";
            server="Server:IBI\r\n";
            CRLF="\r\n";
            response=status+length+type+server+CRLF+messageBody;
		}
		System.out.println(status);
        return response.getBytes();
    }

    private static byte[] extractBytes (String input) throws IOException {
        File file = new File(input);
        byte[] fileContent = Files.readAllBytes(file.toPath());
        return fileContent;
       }
}