#!/bin/bash
# Comparission of different method for determining if a string is a number
# under bash (formated output, handling UTF8 and Latin1 output)
# (C) 2020-2022 Felix Hauri - felix@f-hauri.ch
# Licensed under terms of GPL v3. www.gnu.org

isuint_Parm() { [ "$1" ] && [ -z "${1//[0-9]}" ] ;}
isuint_Grep() { grep -qE '^[0-9]+$' <<<"$1"; }
isuint_Bash() { set -- ${1//[+-]/.}; (( 10#$1 >= 0 )) 2> /dev/null ;}

isuint_Case() { case $1 in ''|*[!0-9]*) return 1;;esac;}
isuint_Regx() { [[ $1 =~ ^[0-9]+$ ]] ;}

isint_Parm() { local chk=${1#[+-]}; [ "$chk" ] && [ -z "${chk//[0-9]}" ] ;}
isint_Bash() { set -- "${1//[!+-]}" ${1#${1//[!+-]}};
	       (( ( 0 ${1:-+} 10#$2 ) ? 1:1 )) 2> /dev/null ;}
isint_Shell() {  [ -n "$1" ] && [ "$1" -eq "$1" ] 2>/dev/null;}
isint_Case() { case ${1#[-+]} in ''|*[!0-9]*) return 1;;esac;}
isint_Regx() { [[ $1 =~ ^[+-]?[0-9]+$ ]] ;}

isnum_Parm() { local ck=${1#[+-]};ck=${ck/.};[ "$ck" ]&&[ -z "${ck//[0-9]}" ];}
isnum_Regx() { [[ $1 =~ ^[+-]?([0-9]+([.][0-9]*)?|\.[0-9]+)$ ]] ;}
isnum_Case() { case ${1#[-+]} in ''|.|*[!0-9.]*|*.*.*) return 1;; esac ;}

testcases=(
  0 1 42 -3 +42 +3. .9 3.14 +3.141 -31.4 '' . 3-3 3.1.4 3a a3 blah 'Good day!'
)

printf '%-12s %4s %4s %4s %4s %4s %4s %4s %4s %4s %4s %4s %4s %4s\n' \
       Value\\Func U{Prm,Grp,Bsh,Cse,Rgx} I{Prm,Shl,Bsh,Cse,Rgx} N{Prm,Cse,Rgx}

for var in "${testcases[@]}"; do
    outstr=''
    for func in isuint_{Parm,Grep,Bash,Case,Regx} \
		isint_{Parm,Shell,Bash,Case,Regx} isnum_{Parm,Case,Regx}; do
	if $func "$var"
        then outstr+='   ##'
        else outstr+='   --'
        fi
    done
    printf '%-11s %s\n' "|$var|" "$outstr"
done

testFunc() {
    local tests=1000 start=${EPOCHREALTIME//.}
    for ((;tests--;)) ;do
        "$1" "$3"
    done
    printf -v "$2" %u $((${EPOCHREALTIME//.}-start))
}

case $LANG in
    *.utf8|*.UTF8|*.utf-8|*.UTF-8 ) mu=$'\u00B5';;
    * ) mu=$'\265';;
esac
strU8DiffLen() { local chLen=${#1} LANG=C LC_ALL=C;return $((${#1}-chLen));}
percent(){ local p=00$((${1}00000/$2));printf -v "$3" %.2f%% ${p::-3}.${p: -3};}
sortedTests() {
    local func NaNTime NumTime ftyp="$1" nTest="$2" tTest="$3" min i pct line
    local -a order=()
    shift 3
    for func ;do
        testFunc "${ftyp}_$func" NaNTime "$tTest"
        testFunc "${ftyp}_$func" NumTime "$nTest"
        order[NaNTime+NumTime]=${ftyp}_$func\ $NumTime\ $NaNTime
    done
    printf '\n%-12s %14s %14s %16s %11s\n' Function Number NaN Total Rank
    min="${!order[*]}" min=${min%% *}
    for i in "${!order[@]}";do
        read -ra line <<<"${order[i]}"
        percent "$i" "$min" pct
	printf -v tnum %\'d "${line[1]}"
	strU8DiffLen "$tnum";dnum=$?
	printf -v tnan %\'d "${line[2]}"
	strU8DiffLen "$tnan";dnan=$?
	printf -v ttot %\'d "$i" 
	strU8DiffLen "$ttot"
        printf "%-12s %*s${mu}s %*s${mu}s  %*s${mu}s  %10s\n" \
               "${line[0]}" $((12+dnum)) "$tnum" $((12+dnan)) "$tnan" \
	       $((13+$?)) "$ttot" "$pct"
    done
}

sortedTests isuint "This is not a number." 31415926535897932384 \
            Case Grep Parm Bash Regx ;\
sortedTests isint  "This is not a number." 31415926535897932384 \
            Case Parm Shell Bash Regx ;\
sortedTests isnum "This string is clearly not a number..." \
            3.141592653589793238462643383279502884  Case Parm Regx