/**
 * 
 * HttpStreamScanner.cpp: Scannes HttpClient stream for lines. Supports chunking.
 * 
 * MIT License
 * 
 * Copyright (c) 2020 InfluxData
 * 
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 * 
 * The above copyright notice and this permission notice shall be included in all
 * copies or substantial portions of the Software.
 * 
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
*/
#include "HttpStreamScanner.h"

// Uncomment bellow in case of a problem and rebuild sketch
//#define INFLUXDB_CLIENT_DEBUG_ENABLE
#include "util/debug.h"
#include "util/helpers.h"

HttpStreamScanner::HttpStreamScanner(HTTPClient *client, bool chunked)
{
    _client = client;
    _stream = client->getStreamPtr();
    _chunked = chunked;
    _chunkHeader = chunked;
    _len = client->getSize();
    INFLUXDB_CLIENT_DEBUG("[D] HttpStreamScanner: chunked: %s, size: %d\n", bool2string(_chunked), _len);
}

bool HttpStreamScanner::next() {
    while(_client->connected() && (_len > 0 || _len == -1)) {
        _line = _stream->readStringUntil('\n');
        INFLUXDB_CLIENT_DEBUG("[D] HttpStreamScanner: line: %s\n", _line.c_str());
        ++_linesNum;
        int lineLen = _line.length();
        if(lineLen == 0) {
            _error = HTTPC_ERROR_READ_TIMEOUT;
            return false;
        } 
        int r = lineLen +1; //+1 for terminating \n
        _line.trim(); //remove \r
        if(!_chunked || !_chunkHeader) {
            _read += r;
            if(_lastChunkLine.length() > 0) { //fix broken line
                _line = _lastChunkLine + _line;
                _lastChunkLine = "";
            }
        
        } 
        if(_chunkHeader && r == 2) { //empty line at the end of chunk
            //last line was complete so return
            _line  = _lastChunkLine;
            _lastChunkLine = "";
            return true;
        }
        if(_chunkHeader){
            _chunkLen = (int) strtol((const char *) _line.c_str(), NULL, 16);
            INFLUXDB_CLIENT_DEBUG("[D] HttpStreamScanner chunk len: %d\n", _chunkLen);
            _chunkHeader = false;
            _read = 0;
            if(_chunkLen == 0) { //last chunk
                _error = 0;
                _line = "";
                return false;
            } else {
                continue;
            }
        } else if(_chunked && _read >= _chunkLen){ //we reached end of chunk. 
            _lastChunkLine = _line;
            _chunkHeader = true;
            continue;
        }
        
        if(_len > 0) {
            _len -= r;
            INFLUXDB_CLIENT_DEBUG("[D] HttpStreamScanner new len: %d\n", _len);
        }
        return true;
    }
    if(!_client->connected() && ( (_chunked && _chunkLen > 0) || (!_chunked && _len > 0))) { //report error only if we didn't went to 
        _error = HTTPC_ERROR_CONNECTION_LOST;
        INFLUXDB_CLIENT_DEBUG("HttpStreamScanner connection lost\n");
    } 
    return false;
}

void HttpStreamScanner::close() {
    _client->end();
}