#!/bin/bash

OLD="2006-12-01 12:30"
NEW="2006-12-04 12:43"

TIME="$(((`date +%s -d "${NEW}"` - `date +%s -d "${OLD}"`)))" #SHOW SEC

echo "$TIME secs"

# if over 48 houers show as days
if [[ "$(($TIME / 60 / 60 ))" -ge "48" ]]
then
#show Days
SPLIT=$(bc << EOF
scale=1
($TIME / 60 / 60 / 24)
EOF
)
echo "$SPLIT Day(s) between old and new dato"

# if under 2 days.. show as houers
elif [[ "$(($TIME /60))" -ge "60" ]] && [[ "$(($TIME / 60/ 60))" -le "48" ]]
then
#show Houers
SPLIT=$(bc << EOF
scale = 2
($TIME / 60 / 60)
EOF
)
echo "$SPLIT Houer(s) between old and new dato"

# if less than 1 houer show as minutes
elif [[ "$(($TIME /60))" -lt "60" ]]
then
#show minutes
SPLIT=$(bc << EOF
scale=1
($TIME / 60)
EOF
)
echo "$SPLIT Minute(s) between old and new Dato"
fi






#######

without set -x

259980 secs
3.0 Day(s) between old and new dato


###### 
with set -x



+ OLD='2006-12-01 12:30'
+ NEW='2006-12-04 12:43'
++ date +%s -d '2006-12-04 12:43'
++ date +%s -d '2006-12-01 12:30'
+ TIME=259980
+ echo '259980 secs'
259980 secs
+ [[ 72 -ge 48 ]]
++ bc
+ SPLIT=3.0
+ echo '3.0 Day(s) between old and new dato'
3.0 Day(s) between old and new dato
nuxil@Nuxil:~/Mine script/bash$