amalthea.terminal source code

1 /* This file is part of the Amalthea library.
2  *
3  * Copyright (C) 2018-2020 Eugene 'Vindex' Stulin
4  *
5  * Distributed under the Boost Software License 1.0 or (at your option)
6  * the GNU Lesser General Public License 3.0 or later.
7  */
8 
9 module amalthea.terminal;
10 
11 public import amalthea.libcore;
12 
13 import std.file, std.stdio;
14 
15 
16 /*******************************************************************************
17  * Colors of foreground.
18  */
19 enum FGColor {
20     black      = "\033[30m",    dark_gray     = "\033[90m",
21     red        = "\033[31m",    light_red     = "\033[91m",
22     green      = "\033[32m",    light_green   = "\033[92m",
23     yellow     = "\033[33m",    light_yellow  = "\033[93m",
24     blue       = "\033[34m",    light_blue    = "\033[94m",
25     magenta    = "\033[35m",    light_magenta = "\033[95m",
26     cyan       = "\033[36m",    light_cyan    = "\033[96m",
27     light_gray = "\033[37m",    white         = "\033[97m",
28 
29     reset = "\033[0m",
30     empty = ""
31 }
32 
33 
34 /*******************************************************************************
35  * Output of color text.
36  */
37 void cwrite(S...)(S args) {
38     File f = stdout;
39     static if (is(typeof(args[0]) == File)) {
40         f = args[0];
41     }
42     string text;
43     FGColor lastColorMark;
44     foreach(i, arg; args) {
45         static if (is(typeof(arg) == FGColor)) {
46             lastColorMark = arg;
47             text ~= cast(string)(arg);
48         } else static if (!is(typeof(arg) == File)) {
49             text ~= to!string(arg);
50         }
51     }
52     f.write(text);
53     if (lastColorMark != FGColor.empty)
54         f.write(cast(string)FGColor.reset);
55     f.flush();
56 }
57 
58 
59 /*******************************************************************************
60  * Output of color text with line ending.
61  */
62 void cwriteln(S...)(S args) {
63     cwrite(args, "\n");
64 }
65 
66 
67 private extern(C) int isatty(int);
68 
69 /*******************************************************************************
70  * Wrapper for `isatty` (see: `man isatty`).
71  * Tests whether a file descriptor refers to a terminal.
72  * Params:
73  *     f = File object. Usually, it is equal to stdout, stderr or stdin.
74  */
75 bool isTTY(File f = stdout) {
76     return cast(bool)isatty(f.fileno);
77 }
78 alias isTerminal = isTTY;
79 
80 
81 /*******************************************************************************
82  * This function clears current terminal screen.
83  */
84 void clearScreen() {
85     write("\033[H\033[2J");
86 }
87