draw.c

   1 #include <stdlib.h>
   2 #include <string.h>
   3 #include <stdio.h>
   4 #include <sys/ioctl.h>
   5
   6 #include "main.h"
   7
   8
   9 /*
  10  * Print a line to stderr.
  11  */
  12 void
  13 draw_line(Line *line, int current, int cols, Opt *opt)
  14 {
  15         size_t i;
  16         int n = 0;
  17         char *content = expand_tabs(line->content);
  18         char *comment = expand_tabs(line->comment);
  19
  20         /* clean the line and add a small margin */
  21         fputs("\033[K", stderr);
  22
  23         /* line number if option set */
  24         if (opt->line_numbers) {
  25                 fputs(current ? "\033[1m" : "\033[1;30m", stderr);
  26                 fprintf(stderr, "%7d\033[0m ", line->number);
  27                 n += 8;
  28         } else {
  29                 fputs("  ", stderr);
  30                 n += 2;
  31         }
  32
  33         /* highlight current line */
  34         if (current)
  35                 fputs("\033[1;33m", stderr);
  36
  37         /* print content without overflowing terminal width */
  38         for (i = 0; i < strlen(content) && n < cols; n++, i++)
  39                 fputc(content[i], stderr);
  40
  41         /* shift without overflowing terminal width */
  42         if (!line->header && line->comment[0] != '\0') {
  43                 /* MAX with '1' as \033[0C still move 1 to the right */
  44                 fprintf(stderr, "\033[%dC", MAX(40 - n, 1));
  45                 n += MAX(40 - n, 1);
  46         }
  47
  48         /* comments in grey */
  49         fputs("\033[1;30m", stderr);
  50
  51         /* print comment without overflowing terminal width */
  52         for (i = 0; i < strlen(comment) && n < cols; n++, i++)
  53                 fputc(comment[i], stderr);
  54
  55         fputs("\033[0m\n", stderr);
  56
  57         free(content);
  58         free(comment);
  59 }
  60
  61
  62 /*
  63  * Print all the lines from an array of pointer to lines.
  64  *
  65  * The total number oflines printed shall not excess 'count'.
  66  */
  67 void
  68 draw_lines(Buffer *buffer, int count, int cols, Opt *opt)
  69 {
  70         Line *line = buffer->current;
  71         int i = 0;
  72         int j = 0;
  73
  74         /* seek back from current line to the first line to print */
  75         while (line && i < count - OFFSET) {
  76                 i    = line->matches ? i + 1 : i;
  77                 line = line->prev;
  78         }
  79         line = line ? line : buffer->first;
  80
  81         /* print up to count lines that match the input */
  82         while (line && j < count) {
  83                 if (line->matches) {
  84                         draw_line(line, line == buffer->current, cols, opt);
  85                         j++;
  86                 }
  87
  88                 line = line->next;
  89         }
  90
  91         /* continue up to the end of the screen clearing it */
  92         for (; j < count; j++)
  93                 fputs("\r\033[K\n", stderr);
  94 }
  95
  96
  97 /*
  98  * Update the screen interface and print all candidates.
  99  *
 100  * This also has to clear the previous lines.
 101  */
 102 void
 103 draw_screen(Buffer *buffer, int tty_fd, Opt *opt)
 104 {
 105         struct winsize w;
 106         int count;
 107
 108         ioctl(tty_fd, TIOCGWINSZ, &w);
 109         count = MIN(opt->lines, w.ws_row - 2);
 110
 111         fputs("\n", stderr);
 112         draw_lines(buffer, count, w.ws_col, opt);
 113
 114         /* go up to the prompt position and update it */
 115         fprintf(stderr, "\033[%dA", count + 1);
 116         draw_prompt(buffer, w.ws_col, opt);
 117 }
 118
 119
 120 void
 121 draw_clear(int lines)
 122 {
 123         int i;
 124
 125         for (i = 0; i < lines + 1; i++)
 126                 fputs("\r\033[K\n", stderr);
 127         fprintf(stderr, "\033[%dA", lines + 1);
 128 }
 129
 130
 131 /*
 132  * Print the prompt, before the input, with the number of candidates that
 133  * match.
 134  */
 135 void
 136 draw_prompt(Buffer *buffer, int cols, Opt *opt)
 137 {
 138         size_t  i;
 139         int     matching = buffer->matching;
 140         int     total    = buffer->total;
 141         char   *input    = expand_tabs(buffer->input);
 142         char   *suggest  = expand_tabs(buffer->current->content);
 143
 144         /* for the '/' separator between the numbers */
 145         cols--;
 146
 147         /* number of digits */
 148         for (i = matching; i; i /= 10, cols--);
 149         for (i = total;    i; i /= 10, cols--);
 150
 151         /* 0 also has one digit*/
 152         cols -= !matching ? 1 : 0;
 153
 154         /* actual prompt */
 155         fprintf(stderr, "\r%s\033[K> ", opt->prompt);
 156         cols -= 2 + strlen(opt->prompt);
 157
 158         /* input without overflowing terminal width */
 159         for (i = 0; i < strlen(input) && cols > 0; cols--, i++)
 160                 fputc(input[i], stderr);
 161
 162         /* save the cursor position at the end of the input */
 163         fputs("\033[s", stderr);
 164
 165         /* grey */
 166         fputs("\033[1;30m", stderr);
 167
 168         /* suggest without overflowing terminal width */
 169         if (opt->complete && buffer->matching > 0) {
 170                 for (; i < strlen(suggest) && cols > 0; cols--, i++)
 171                         fputc(suggest[i], stderr);
 172         }
 173
 174         /* go to the end of the line */
 175         fprintf(stderr, "\033[%dC", cols);
 176
 177         /* total match and line count at the end of the line */
 178         fprintf(stderr, "%d/%d", matching, total);
 179
 180         /* restore cursor position at the end of the input */
 181         fputs("\033[0m\033[u", stderr);
 182
 183         free(input);
 184         free(suggest);
 185 }