// ADAPTED FROM: https://github.com/espressif/arduino-esp32/blob/master/libraries/WebServer/examples/FSBrowser/FSBrowser.ino

#define FILESYSTEM SPIFFS
#define FORMAT_FILESYSTEM true
#define DBG_OUTPUT_PORT Serial


//holds the current upload
File fsUploadFile;

//format bytes
String formatBytes(size_t bytes) {
  if (bytes < 1024) {
    return String(bytes) + "B";
  } else if (bytes < (1024 * 1024)) {
    return String(bytes / 1024.0) + "KB";
  } else if (bytes < (1024 * 1024 * 1024)) {
    return String(bytes / 1024.0 / 1024.0) + "MB";
  } else {
    return String(bytes / 1024.0 / 1024.0 / 1024.0) + "GB";
  }
}

String getContentType(String filename) {
  if (webServer.hasArg("download")) {
    return "application/octet-stream";
  } else if (filename.endsWith(".htm")) {
    return "text/html";
  } else if (filename.endsWith(".html")) {
    return "text/html";
  } else if (filename.endsWith(".css")) {
    return "text/css";
  } else if (filename.endsWith(".js")) {
    return "application/javascript";
  } else if (filename.endsWith(".png")) {
    return "image/png";
  } else if (filename.endsWith(".gif")) {
    return "image/gif";
  } else if (filename.endsWith(".jpg")) {
    return "image/jpeg";
  } else if (filename.endsWith(".ico")) {
    return "image/x-icon";
  } else if (filename.endsWith(".xml")) {
    return "text/xml";
  } else if (filename.endsWith(".pdf")) {
    return "application/x-pdf";
  } else if (filename.endsWith(".zip")) {
    return "application/x-zip";
  } else if (filename.endsWith(".gz")) {
    return "application/x-gzip";
  }
  return "text/plain";
}

bool exists(String path){
  bool yes = false;
  File file = FILESYSTEM.open(path, "r");
  if(!file.isDirectory()){
    yes = true;
  }
  file.close();
  return yes;
}

bool handleFileRead(String path) {
  DBG_OUTPUT_PORT.println("handleFileRead: " + path);
  if (path.endsWith("/")) {
    path += "index.htm";
  }
  String contentType = getContentType(path);
  String pathWithGz = path + ".gz";
  if (exists(pathWithGz) || exists(path)) {
    if (exists(pathWithGz)) {
      path += ".gz";
    }
    File file = FILESYSTEM.open(path, "r");
    webServer.streamFile(file, contentType);
    file.close();
    return true;
  }
  return false;
}

void handleFileUpload() {
  if (webServer.uri() != "/edit") {
    return;
  }
  HTTPUpload& upload = webServer.upload();
  if (upload.status == UPLOAD_FILE_START) {
    String filename = upload.filename;
    if (!filename.startsWith("/")) {
      filename = "/" + filename;
    }
    DBG_OUTPUT_PORT.print("handleFileUpload Name: "); DBG_OUTPUT_PORT.println(filename);
    fsUploadFile = FILESYSTEM.open(filename, "w");
    filename = String();
  } else if (upload.status == UPLOAD_FILE_WRITE) {
    //DBG_OUTPUT_PORT.print("handleFileUpload Data: "); DBG_OUTPUT_PORT.println(upload.currentSize);
    if (fsUploadFile) {
      fsUploadFile.write(upload.buf, upload.currentSize);
    }
  } else if (upload.status == UPLOAD_FILE_END) {
    if (fsUploadFile) {
      fsUploadFile.close();
    }
    DBG_OUTPUT_PORT.print("handleFileUpload Size: "); DBG_OUTPUT_PORT.println(upload.totalSize);
  }
}

void handleFileDelete() {
  if (webServer.args() == 0) {
    return webServer.send(500, "text/plain", "BAD ARGS");
  }
  String path = webServer.arg(0);
  DBG_OUTPUT_PORT.println("handleFileDelete: " + path);
  if (path == "/") {
    return webServer.send(500, "text/plain", "BAD PATH");
  }
  if (!exists(path)) {
    return webServer.send(404, "text/plain", "FileNotFound");
  }
  FILESYSTEM.remove(path);
  webServer.send(200, "text/plain", "");
  path = String();
}

void handleFileCreate() {
  if (webServer.args() == 0) {
    return webServer.send(500, "text/plain", "BAD ARGS");
  }
  String path = webServer.arg(0);
  DBG_OUTPUT_PORT.println("handleFileCreate: " + path);
  if (path == "/") {
    return webServer.send(500, "text/plain", "BAD PATH");
  }
  if (exists(path)) {
    return webServer.send(500, "text/plain", "FILE EXISTS");
  }
  File file = FILESYSTEM.open(path, "w");
  if (file) {
    file.close();
  } else {
    return webServer.send(500, "text/plain", "CREATE FAILED");
  }
  webServer.send(200, "text/plain", "");
  path = String();
}

void handleFileList() {
  if (!webServer.hasArg("dir")) {
    webServer.send(500, "text/plain", "BAD ARGS");
    return;
  }

  String path = webServer.arg("dir");
  DBG_OUTPUT_PORT.println("handleFileList: " + path);


  File root = FILESYSTEM.open(path);
  path = String();

  String output = "[";
  if(root.isDirectory()){
      File file = root.openNextFile();
      while(file){
          if (output != "[") {
            output += ',';
          }
          output += "{\"type\":\"";
          output += (file.isDirectory()) ? "dir" : "file";
          output += "\",\"name\":\"";
          output += String(file.name()).substring(1);
          output += "\"}";
          file = root.openNextFile();
      }
  }
  output += "]";
  webServer.send(200, "text/json", output);
}