threaded_network_chat/disp.cc

#include <fstream>

#include <curses.h>

#include "disp.h"
#include "public.h"

// clears ncurses rows in a specific region only
void
clearRows(int startingRow, int endingRow)
{
	// preserve the cursor location
	int yBefore, xBefore;
	getyx(stdscr, yBefore, xBefore);

	for (int i = startingRow; i < endingRow; i++) {
		move(i, 0);
		clrtoeol(); // clear to end of line
	}

	// restore original cursor location
	move(yBefore, xBefore);
}

// display a file using ncurses
int
displayFile(string path, int startLineNum = 0, int numLines = 10)
{
	ifstream file(path);
	if (!file) {
		return 1;
	} else {
		clearRows(0, numLines + 1); // clear the chat area
		int lineNum = 0;
		string line;

		// print each line directly to the screen
		int num = 0;
		while (getline(file, line) &&
		       num <= numLines + startLineNum + 1) // while there is file content and the
							   // line number isn't too high
		{
			if (num >= startLineNum) {
				move(lineNum, 0);
				printw("%s", line.c_str());
				lineNum++; // increment the row number after
					   // printing each line
			}
			num++;
		}
		move(DEFAULT_CUR_Y, DEFAULT_CUR_X);
		refresh();
		return 0;
	}
}