shlide (view raw)
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 |
#!/usr/bin/env bash
#
# Usage: shlide path/to/slides/
# Each slide is a textfile under path/to/slides
# Color definitions
BLK="\e[30m"
RED="\e[31m"
GRN="\e[32m"
YLW="\e[33m"
BLU="\e[34m"
PUR="\e[35m"
CYN="\e[36m"
RST="\e[0m"
lines() {
mapfile -tn 0 lines < "$1"
printf '%s\n' "${#lines[@]}"
}
longest_line() {
max=0 IFS=
while read -r line; do
if [ "${#line}" -gt "$max" ]; then max="${#line}"; fi
done < "$1"
printf '%s\n' "$max"
}
display() {
# 1 - slide contents
# 2 - slide name
# 3 - current slide nr.
# 4 - total nr. of slides
slide_contents="$1"
# Hides the cursor.
printf '\e[?25l'
# Clear the screen.
printf '\e[2J'
# Get screen size
shopt -s checkwinsize; (:;:)
# Write slide number at bottom left
printf '\e[H'
printf '\e[%sB%s/%s' "$LINES" "$(($3+1))" "$4"
# Custom calculations to center text
height=$(lines "$2")
width=$(longest_line "$2")
# Rough estimates for the true center.
((l=$LINES/2 - $height/2))
((c=$COLUMNS/2 - $width/2))
printf '\e[%s;%sH' "$l" "$c"
while IFS= read -r line; do
reduce=0
# Print the contents of the slide file,
# line by line.
printf "%s" "$line"
case $line in
"" | *"\n"*)
((++reduce));;
esac
# Move down and back after each print.
printf '\e[%sD\e[B' "$((${#line} - $reduce))"
done <<< "$slide_contents"
}
display_end() {
read -r LINES COLUMNS < <(stty -F /dev/tty size)
((l=$LINES/2))
((c=$COLUMNS/2 - 8))
printf '\e[2J'
printf '\e[0;%sH' "$c"
printf 'END. Press q to quit.'
}
main() {
slides_dir="${1:-./}"
slides=("$slides_dir"/[0-9]*.txt)
i=0
while true; do
# Clear the screen.
printf '\e[2J'
# Display END reached prompt, and then exit
[[ "$i" -eq "${#slides[@]}" ]] && {
display_end
read -rsn1 input
case "$input" in
"j"|"n"|"q")
printf '\e[2J'
printf '\e[?25h'
exit
;;
*)
((--i))
;;
esac
}
# Don't go below 0.
[[ "$i" -lt 0 ]] && i=0
# Navigate on j/k/n/p and quit on q.
display "$(<${slides[$i]})" "${slides[$i]}" "$i" "${#slides[@]}"
read -rsn1 input
case "$input" in
"j"|"n")
((++i))
;;
"k"|"p")
((--i))
;;
"q")
# Return the cursor on exit.
printf '\e[?25h'
exit
;;
esac
done
# Return the cursor.
printf '\e[?25h'
}
main "$@"
|