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