// This file contains some examples of stream manipulation with cin, cout, and
// file-based streams
//
// some common istream operations:
//     ifstream input(name);     initializes ifstream to read from given file
//     ofstream output(name);    initializes ofstream to write to given file
//     stream >> x;              read (extract) x from given input stream
//     stream << x;              write (insert) x to given output stream
//     getline(input, str)       read into str one line from input
//     stream.open(name);        opens the stream to the given file
//     stream.close()            closes the stream
//     istringstream input(str)  make an input stream from the given string
//     ostringstream output()    make an output stream from the given string
//     stream.str()              convert an ostringstream to a string
//     stream.good()             is the stream in a good state?
//     stream.clear()            clear all error flags for the stream
//     stream.eof()              is the end-of-file flag set for this stream
//     stream.get(ch)            reads one char from the stream, setting ch
//     stream.peek(ch)           returns next character to be read

#include <iostream>
#include <string>
#include <vector>
#include <fstream>
#include <sstream>

using namespace std;

// uses the given prompt to prompt the console user for an int and keeps
// prompting until the user provides a legal int
int read_int(const string & prompt) {
    cout << prompt;
    int n;
    while (!(cin >> n)) {
        cout << "That wasn't an int" << endl;
        string dummy;
        cin.clear();
        getline(cin, dummy);
        cout << prompt;
    }
    return n;
}

// processes a file of int values reporting the numbers, their sum, and any
// illegal tokens it encounters in the file
void process_file(string name) {
    ifstream input(name);
    int sum = 0;
    int n;
    while (!input.eof()) {
        if (input >> n) {
            cout << "next int = " << n << endl;
            sum += n;
        } else {
            input.clear();
            string bad;
            if (input >> bad) {
                cout << "skipping illegal token " << bad << endl;
            }
        }
    }
    cout << "sum of file entries = " << sum << endl;
}

// returns a string version of the given int
string int_to_string(int n) {
    ostringstream out;
    out << n;
    return out.str();
}

void count_words(string name) {
    cout << "word counts for file " << name << endl;
    ifstream input(name);
    string line;
    int line_count = 0;
    while (getline(input, line)) {
        line_count++;
        istringstream data(line);
        string token;
        int word_count = 0;
        while (data >> token) {
            word_count++;
        }
        cout << "    line # " << line_count << " has " << word_count
             << " word(s)" << endl;
    }
}

int main() {
    int n = read_int("give me an int: ");
    cout << n << endl;
    cout << endl;

    process_file("data.txt");
    cout << endl;

    ofstream output;
    output.open("foo1.txt");
    output << "what fun" << endl;
    output.close();
    output.open("foo2.txt");
    output << "even more fun" << endl;

    int x = 3, y = 4;
    string s = "x = " + int_to_string(3) + ", y = " + int_to_string(4);
    cout << s << endl;
    cout << endl;

    count_words("jabberwocky.txt");

    return 0;
}