//* Reading numeric data from a file - parsing with strings and stringstreams *
#include <iostream>
#include <fstream>
#include <sstream>
#include <string>
#include <cfloat>
using namespace std;


int main() {
    string inName;
    cout << "Read text from: ";
    cin  >> inName;
    ifstream inFile;
    inFile.open(inName.c_str());
    if (!inFile.is_open()) {
        cout << "ERROR: Cannot open " << inName << " file for reading." << endl;
        return(1);
    }

    string SSIDname;
    cout << "SSID to watch: ";
    cin  >> SSIDname;
    

    double sum=0.0;
    int    cnt=0;
    double max=-DBL_MAX;

    unsigned line=0;
    for (;;) {
        string buffer;
        getline(inFile, buffer);

        if (inFile.fail()) {
            if (inFile.eof()) break; // the failure was caused by the end of file - expected behavior
                              // breaks quits one level of loops - exit the line reading loop - reminder
            cerr << "ERROR: file reading error - data corrupted, exiting at line number " << line << endl;
            break;
        }

        line++;
        cout << line << "\r";

        if (buffer.size()==0 || buffer[0]=='#')
            continue; // next line - comment or empty line

        int p1 = buffer.find("( ");
        if (p1==string::npos) continue; // next line - this one does not contain SSID data
        int p2 = buffer.find(" )", p1+2);
        if (p2==string::npos) continue; // next line - this one does not contain SSID data

        if (buffer.substr(p1+2, p2-p1-2) != SSIDname) continue; // next line - interested only in a particular SSID

        int b1 = buffer.find("[ ", p2);
        if (b1==string::npos) continue; // next line - this one does not contain SNR data
        int b2 = buffer.find(" ]", b1+2);
        if (b2==string::npos) continue; // next line - this one does not contain SNR data


        istringstream inLine(buffer.substr(b1+2, b2-b1-2));

        double x, y, z;
        inLine >> x >> y >> z;

        if (inLine.fail()) {
            cerr << "WARNING: Ignored corrupt SNR data in line " << line << endl;
            continue; // continue goes to the loop control early
        }

        sum=sum+x;
        cnt++;
        if (max<x)
            max=x;

    }
    inFile.clear();
    inFile.close();

    if (cnt==0)
        cout << "No data!" << endl;
    else {
        cout << "total: " << line << endl;
        cout << "data = " << cnt  << endl;
        cout << "avg  = " << sum/cnt << endl;
        cout << "max  = " << max  << endl;
    }

    return(0);
}
/*
Read text from: wifi.txt
SSID to watch: MMTEK
total: 40481
data = 1888
avg  = 27.0524
max  = 34
Press any key to continue . . .
*/