#!/bin/sh

log_directory=~/log
log_sample="Lundi:\n
\n
Mardi:\n
\n
Mercredi:\n
\n
Jeudi:\n
\n
Vendredi:\n
"

SPM=60
MPH=60
HPD=24

mode_available="view edit list toMail"

usage () {
    echo "usage : $0 mode [date] "
    echo "with mode in :"
    for i in $mode_available;
    do
        echo -e "$i "
    done
    echo ""
}

read_date () {
    if [ -z $1 ]; then
        return 0
    fi
	day=${1#*_*_}
	tmp=${1%_*}
	month=${tmp#*_}
	year=${tmp%_*}

	old=$(date -d "$year-$month-$day" +%s)
	new=$(date +%s)

	diff=$new-$old
	return $((diff / SPM / MPH / HPD))

}

check_valid_argument () {
    needle=$1
    for hay in $2; do
        [[ $hay == $needle ]] && return 1
    done
    return 0
}

create_file () {
    if [ ! -e $1 ]
    then
        mkdir -p $log_directory
        echo -e $log_sample > $1
    fi

}

view () {
    read_date $1
    date_arg=$?
    curr_day=$(date --date="$date_arg days ago" +%u)
    day_to_monday=$(($curr_day -1))
    date_to_edit=$(date  --date="$((date_arg + day_to_monday)) days ago" +%y_%m_%d)

    file=$log_directory/$date_to_edit

    create_file $file
    more $log_directory/$date_to_edit
}

edit () {
    read_date $1
    date_arg=$?
    curr_day=$(date --date="$date_arg days ago" +%u)
    day_to_monday=$(($curr_day -1))
    date_to_edit=$(date  --date="$((date_arg + day_to_monday)) days ago" +%y_%m_%d)

    file=$log_directory/$date_to_edit

    create_file $file
    ${EDITOR} $log_directory/$date_to_edit
}

list () {
    logs=$(ls $log_directory | sort)
    echo "${logs}"
}

toMail () {
    read_date $1
    date_arg=$?
    curr_day=$(date --date="$date_arg days ago" +%u)
    day_to_monday=$(($curr_day -1))
    day_to_friday=$((5 - $curr_day))
    start_date=$(date  --date="$((date_arg + day_to_monday)) days ago" +%y-%m-%d)
    stop_date=$(date  --date="$((date_arg + day_to_friday)) days" +%y-%m-%d)
    echo "Weekly $start_date -> $stop_date"
    view 
}


check_valid_argument $1 "$mode_available"
valid=$?

if [[ $# -ge 1 && $valid = 1 ]]
then
    eval $1 $2
else
    usage
fi