// This object gets between the server and the file system to manage the
//  returned content.
// The interpreter also provides access to to a copy of the request object 
//  and its post data.

var Interpreter = Command.extend({
  constructor: function(request) {
    this.base();
    this.request = pcopy(request);
  },
  
  query: "",
  request: null,

  include_script: function(template) {
    var path = this.makepath(template);
    if (!this[Command.INCLUDES][path] && !Interpreter.SYSTEM.test(this.top)) {
      this.echo("<script type='text/javascript'>\n");
      this.include_once(template);
      this.echo("\n<\/script>\n");
    }
  },

  include_style: function(template) {
    var path = this.makepath(template);
    if (!this[Command.INCLUDES][path] && !Interpreter.SYSTEM.test(this.top)) {
      this.echo("<style type='text/css'>\n");
      this.include_once(template);
      this.echo("\n<\/style>\n");
    }
  },
  
  interpret: function() {
    var url = this.request.url;
    var template = Interpreter.VIEW;
    var status = this.request.status;
    
    if (status > 299) { // return an error page
      target = Interpreter.ERROR + (Interpreter.ERROR_PAGES[status] || Interpreter.DEFAULT);
    } else {
      if (url.indexOf("!") != -1) { // it's a query
        var parts = url.split("!");
        url = parts[0];
        this.query = parts[1];
      }
      var target = url;
      // find a template
      var path = url.split("/");
      do {
        path.pop();
        template = path.join("/") + Interpreter.VIEW;
      } while (path.length && !this.exists(template));
      if (this.isDirectory(target) && this.exists(target + Interpreter.DEFAULT)) {
        target += Interpreter.DEFAULT;
      }
    }
    return this.exec(template, target);
  }
}, {
  DEFAULT:   "default",
  SYSTEM:    /^\/system\/(create|edit|view)$/,
  VIEW:      "/system/view",
  ERROR:     "/system/Error/",
  ERROR_PAGES: {
    "301": "Moved_Permanently",
    "404": "Not_Found",
    "405": "Method_Not_Allowed",
    "500": "Internal_Server_Error"
  }
});