// Time.cpp

#include "Time.h"

#include <iostream>
using std::istream;

istream & operator>>( istream & in, Time & t )
{
    // read hours after skipping whitespace
    int h = 99;
    in >> h;
    // Note: we don't read directly into t.hours_ so we can leave
    // it unchanged in case of an error.
    if ( in.fail() || in.bad() ) return in; // no int in stream
    if ( in.eof() || h < 0 || h > 23 ) {
            // if eof, an int but nothing else
        in.setstate(in.failbit);  // add fail state to stream
        return in;
    }

    // make sure next char is colon
    char next_char = in.peek();
    // Note: we don't read the char until we're sure it's a colon.
    if ( !in ) return in;
    // Note: bad or good were the only possibilities.
    if ( next_char != ':' ) {
        in.setstate(in.failbit);
        return in;
    }
    in.get(); // read colon

    // make sure next char is not whitespace
    next_char = in.peek();
    if ( !in ) return in;
    if ( next_char == ' ' || next_char == '\t'
            || next_char == '\n' ) {
        in.setstate(in.failbit);
        return in;
    }

    // read minutes
    int m = 99;
    in >> m;
    if ( in.fail() || in.bad() ) return in;
    // Note: eof is possible if the minutes were at the very
    // end of the file.  This shouldn't make the time invalid
    // but we leave the stream in the eof state.
    if ( m < 0 || m > 59 ) {
        in.setstate(in.failbit);
        return in;
    }

    // all good (except possibly for the number of digits in
    // the hours and minutes)
    t.set_hours(h);
    t.set_minutes(m);
    return in;
}