#include "HTTPRequest.h"
#include "Exception.h"
#include <strings.h>

namespace coreutils {

   HTTPRequest::HTTPRequest(StreamReader &reader) : Parser(reader) {}

   HTTPRequest::~HTTPRequest() {
      delete lineParser;
      delete headerParser;
      delete formParser;
   }

   Parser::Status HTTPRequest::parse() {
      MString &buffer = reader.getBuffer();

      switch (state) {

       case REQUEST_LINE: {
          if (!lineParser)
             lineParser = new LineParser(reader);
          if (!checkParse(*lineParser))
             return Status::INCOMPLETE;
          {
             ZString line = lineParser->getLine();
             ZString sp(" ");
             std::vector<ZString> &parts = line.split(sp);
             if (parts.size() != 3)
                throw coreutils::Exception("HTTPRequest: malformed request line "
                                            "(expected \"METHOD /path HTTP/1.1\").");
             method = MString(parts[0]);
             path = MString(parts[1]);
             version = MString(parts[2]);
          }
          delete lineParser;
          lineParser = NULL;
          {
             // Split the query string off before anything else sees `path` -
             // a route table (see the APIServer plan) should never have to
             // deal with a trailing "?a=1&b=2" itself.
             int qpos = path.find(ZString("?"));
             if (qpos != -1) {
                queryString = MString(path.substring(qpos + 1));
                path = MString(path.substring(0, qpos));
             }
          }
          state = HEADERS;
          return Status::DATA_AVAIL;
       }

       case HEADERS:
          if (!headerParser)
             headerParser = new IMFHeader(reader);
          if (!checkParse(*headerParser))
             return Status::INCOMPLETE;
          headers = headerParser->getHeaders();
          delete headerParser;
          headerParser = NULL;
          state = BODY;
          return Status::DATA_AVAIL;

       case BODY: {
          MString contentLengthHeader = getHeader("Content-Length");
          if (contentLengthHeader.getLength() == 0) {
             if (getHeader("Transfer-Encoding").getLength() > 0)
                throw coreutils::Exception("HTTPRequest: chunked Transfer-Encoding "
                                            "is not supported (Content-Length only).");
             state = DONE;
             return Status::COMPLETE;
          }
          int contentLength = contentLengthHeader.asInteger();
          MString contentType = getHeader("Content-Type");
          if (contentType.startsWith("application/x-www-form-urlencoded") ||
              contentType.startsWith("multipart/form-data")) {
             if (!formParser) {
                // Mirrors __jet.cpp's identical CGI-path fix: find() leaves
                // contentType's own cursor at the match, and CGIFormData's
                // constructor copy-constructs its own contentType member
                // from whatever we pass, inheriting that same moved cursor
                // - its startsWith() dispatch checks are cursor-relative
                // and would silently miss (falling through to UNKNOWN)
                // without the reset().
                int boundaryPos = contentType.find(ZString("boundary="));
                if (boundaryPos != -1)
                   boundary = MString(contentType.substring(boundaryPos + 9));
                contentType.reset();
                formParser = new CGIFormData(reader, contentType, contentLength, boundary);
             }
             if (!checkParse(*formParser))
                return Status::INCOMPLETE;
             state = DONE;
             return Status::COMPLETE;
          }
          if ((int)buffer.getLength() < contentLength)
             return Status::INCOMPLETE;
          body = MString(ZString(buffer.getCursor(), contentLength));
          buffer.setCursor(buffer.getCursor() + contentLength);
          state = DONE;
          return Status::COMPLETE;
       }

       case DONE:
          return Status::COMPLETE;

      }
      throw coreutils::Exception("HTTPRequest: unreachable state.");
   }

   MString HTTPRequest::getMethod() { return method; }
   MString HTTPRequest::getPath() { return path; }
   MString HTTPRequest::getQueryString() { return queryString; }
   MString HTTPRequest::getVersion() { return version; }
   MString HTTPRequest::getBody() { return body; }
   std::map<MString, MString> &HTTPRequest::getHeaders() { return headers; }
   CGIFormData *HTTPRequest::getFormData() { return formParser; }

   MString HTTPRequest::getHeader(const char *name) {
      for (auto &pair : headers) {
         MString key = pair.first;
         if (strcasecmp(key.c_str(), name) == 0)
            return pair.second;
      }
      return MString();
   }

}