#ifndef SINGLEREADQ
#define SINGLEREADQ

#include<cmath>
#include<cstdio>
#include<cstdlib>
#include<cassert>
#include<string>
#include<iostream>

#include "utils.h"
#include "Read.h"

class SingleReadQ : public Read {
 public:
  SingleReadQ() { readseq = qscore = ""; len = 0; }
  SingleReadQ(const std::string& name, const std::string& readseq, const std::string& qscore) {
	  this->name = name;
	  this->readseq = readseq;
	  this->qscore = qscore;
	  this->len = readseq.length();

	  calc_lq();
  }

  bool read(int argc, std::istream* argv[], int flags = 7);
  void write(int argc, std::ostream* argv[]);

  int getReadLength() const { return len; }
  const std::string& getReadSeq() const { return readseq; }
  const std::string& getQScore() const { return qscore; }

 private:
  int len; // read length
  std::string readseq, qscore; // qscore : quality scores

  void calc_lq();
};

bool SingleReadQ::read(int argc, std::istream* argv[], int flags) {
  std::string line;

  assert(argc == 1);
  if (!getline((*argv[0]), line)) return false;
  if (line[0] != '@') { fprintf(stderr, "Read file does not look like a FASTQ file!\n"); exit(-1); }
  name = "";
  if (flags & 4) { name = line.substr(1); }
  if (!getline((*argv[0]), readseq)) return false;
  len = readseq.length();
  if (!(flags & 1)) { readseq = ""; }
  if (!getline((*argv[0]), line)) return false;
  if (line[0] != '+') { fprintf(stderr, "Read file does not look like a FASTQ file!\n"); exit(-1); }
  if (!getline((*argv[0]), qscore)) return false;
  if (!(flags & 2)) { qscore = ""; }

  if (flags & 1) calc_lq();

  return true;
}

void SingleReadQ::write(int argc, std::ostream* argv[]) {
	assert(argc == 1);
	(*argv[0])<<"@"<<name<<std::endl<<readseq<<std::endl<<"+\n"<<qscore<<std::endl;
}

void SingleReadQ::calc_lq() {
  int numA = 0, numT = 0, numAO = 0, numTO = 0; // numAO : number of A in overlap seed region
  int threshold_1, threshold_2;

  threshold_1 = int(0.9 * len - 1.5 * sqrt(len * 1.0) + 0.5);
  threshold_2 = (OLEN - 1) / 2 + 1;
  for (int i = 0; i < len; i++) {
    if (readseq[i] == 'A') { 
      ++numA;
      if (i < OLEN) ++numAO;
    }
    if (readseq[i] == 'T') {
      ++numT;
      if (i >= len - OLEN) ++numTO; 
    }
  }
  
  if (numA >= threshold_1) {
    low_quality = (numAO >= threshold_2);
  }
  else if (numT >= threshold_1) {
    low_quality = (numTO >= threshold_2);
  }
  else low_quality = false;
}

#endif
