#!/bin/bash
#==========================================================
# Simple Note System, v2.0a3
# Copyright 2014, Xenese Labs/Sicron-Perion XNF
#==========================================================

PROD_STR="Simple Note System"
VER_STR="v2.0a3"

# Section: Functions
function init_default_config() {
if [ -z "$ROOTDIR" ]; then
    ROOTDIR=$HOME/.sns
fi
if [ -z "$BASEDIR" ]; then
    BASEDIR=$ROOTDIR/notes
fi
if [ -z "$EXT" ]; then
    EXT=note
fi
if [ -z "$EDITOR" ]; then
    EDITOR=vim
fi
if [ -z "$ENC_KEY" ]; then
    ENCRYPTION="FALSE"
else
    ENCRYPTION="TRUE"
fi
}
function w_conf {
cat > $HOME/.sns/sns.conf << EOF
#==========================================================
# Simple Note System Config, v2.0a1
# Copyright 2014, Xenese Labs/Sicron-Perion XNF
#==========================================================

#Directory where notes will be stored
ROOTDIR=$HOME/.sns
BASEDIR=$ROOTDIR/notes

#File extension to use (for listing notes)
EXT=note

#Preferred Editor
EDITOR=vim

#Encryption
#WARNING: ANY PREVIOUSLY UNENCRYPTED NOTES WILL BE LOST
ENCRYPTION="FALSE"
ENC_KEY=""
EOF

chmod 600 $ROOTDIR/sns.conf
}
function pause {
    read -p "  Press [Enter] to continue."
    echo ""
}
function help {
    echo ""
    echo "usage: sns [-ce] NAME NOTEBOOK SECTION"
    echo "       sns [-d ] NAME NOTEBOOK SECTION"
    echo "       sns [-lp] NOTEBOOK"
    echo "       sns [-w ]"
    echo "       sns [-h ]"

    echo ""
    echo "  -c | --create : Create note"
    echo "  -d | --delete : Delete note"
    echo "  -e | --edit   : Open note for editing"
    echo "  -h | --help   : Display this message"
    echo "  -p | --print  : Print note to console"
    echo "  -l | --list   : List all notes in NOTEBOOK"
    echo "  -w | --wconf  : Write default configuration to ~/.sns (useful for Encryption)"
    echo ""
}
function p_header(){
    printf "TITLE: $NAME\nDATE: $(date)\n"
}
#function create(){
#
#   #Check if note exists
#   if [ -e "$NOTE" -o -e ${NOTE%.*} ]; then
#       echo ""
#       echo "ERROR: Note already exists"
#       echo "Hint: use -e to edit the note."
#       echo ""
#       exit
#   else
#       #Create any necessary folders
#       mkdir -p $NOTEDIR
#
#       #Fill in title
#       echo "TITLE: $NAME" > $NOTE
#       #Fill the second line with the date
#        echo "DATE: $(date)" >> $NOTE
#
#       if [ "$ENCRYPTION" == "TRUE" ]; then
#           if [ "$EDIT" == "FALSE" ]; then
#              echo " openssl enc -aes-256-cbc -salt -in $NOTE -out $NOTE.enc -pass pass:$ENC_KEY"
#           fi
#       fi
#   fi
#}

function create(){
    if [ -e "$NOTE" -o -e ${NOTE%.*} ]; then
       printf "\nERROR: Note already exists\nHint: use -e to edit the note.\n"
       exit
    elif [ -z "$ENCRYPTION" ]; then
        echo "TITLE: $NAME" > $NOTE
        echo "DATE: $(date)" >> $NOTE
    elif [ "$ENCRYPTION" == "TRUE" ]; then
        mkdir -p "$NOTEDIR"
        touch "$NOTE"
    echo "$(p_header)" | openssl enc -aes-256-cbc -salt -out "$NOTE"\
    -pass pass:$ENC_KEY

    fi
    echo "$NOTE"
}
function delete(){
    if [ "$DELETE" == "TRUE" ]; then
        if [ -e $NOTE -o -e ${NOTE%.*} ]; then
            if [ "$ENCRYPTION" == "TRUE" ]; then
                rm ${NOTE%.*}
            else
                rm $NOTE
            fi
            echo ""
            echo "Deleted note: $NOTEBOOK/$SECTION$NAME."
            exit
        else
            echo ""
            echo "ERROR: Note $NOTEBOOK/$SECTION$NAME does not exist."
            exit
        fi
    fi
}
function edit (){
    if [ -r "$NOTE" -o -r ${NOTE%.*} ]; then
        #Pre-Processing (Encryption)
        if [ -z "$CREATE" ]; then
            if [ "$ENCRYPTION" == "TRUE" ]; then
                TMP_NAME="$ROOTDIR"/tmp/"$RANDOM"
                openssl enc -d -aes-256-cbc -in $NOTE -pass pass:$ENC_KEY > $TMP_NAME
                echo "" >> $TMP_NAME
                echo "EDIT $(date)" >> $TMP_NAME
                $EDITOR $TMP_NAME
            else
                echo "" >> $NOTE
                echo "EDIT $(date)" >> $NOTE
                $EDITOR $NOTE
            fi
        fi
        #Post-Processing (Encryption)
        if [ "$ENCRYPTION" == "TRUE" ]; then
            openssl enc -aes-256-cbc -salt -in $TMP_NAME -out $NOTE -pass pass:$ENC_KEY
            rm "$TMP_NAME"
        fi

    else
        printf "\nERROR: Note cannot be opened for editting.\n"
    fi
}
function print(){
    if [ "$PRINT" == "TRUE" ]; then
        if [ -r "$NOTE" -o -r ${NOTE%.*} ]; then
            if [ -z "$CREATE" ]; then
                if [ "$ENCRYPTION" == "TRUE" ]; then
                    openssl enc -d -aes-256-cbc -in ${NOTE%.*} -pass pass:$ENC_KEY
                else
                cat $NOTE
                echo "" >> $NOTE
                fi
            else
                echo ""
                echo "ERROR: Note cannot be found."
                echo ""

            fi
        fi
    fi
}
function list(){
    if [ -d "$BASEDIR"/"$NOTEBOOK" ]; then
        echo ""
        printf "Notes in $(basename $NOTEBOOK):"
        echo ""

        NOTES=( $(find $BASEDIR/$NOTEBOOK -name "*.$EXT" -print0 | sed s:$BASEDIR/$NOTEBOOK/:"    ":g | sed -e s:".$EXT"::g | tr "/" " ") )
        let i=0
        for NOTE in ${NOTES[@]}; do
            if [ -d $BASEDIR/$NOTEBOOK/$NOTE ]; then
                if [ "$LAST_SECTION" != "$NOTE" ]; then
                    printf "  Section: $NOTE\n"
                fi
                LAST_SECTION=$NOTE
            else
                #if [ $(($i % 1)) -eq 0 ]; then
                #    printf "\n     "
                #fi
                printf "    $NOTE\n"
            fi
            let i++
        done
        printf "\n"
    else
        echo ""
        echo "ERROR: Notebook $NOTEBOOK does not exist."
        echo ""
    fi
}
# End Section: Functions
#==============================================================================
# Section: Configuration
#==============================================================================
if [ -r $HOME/.sns/sns.conf ]; then
    source $HOME/.sns/sns.conf
else
    init_default_config
fi

if [ "$ENCRYPTION" == "TRUE" ]; then
if [ -z "$ENC_KEY" ]; then
ERR_NO_KEY="TRUE"
ENCRYPTION="FALSE"
fi
command -v openssl >/dev/null 2>&1 || { ERR_NO_SSL="TRUE"; ENCRYPTION="FALSE"; }
fi

if [ "$ENCRYPTION" == "TRUE" ]; then
PROD_STR="Simple Note System (Encryption Enabled)"
EXT="$EXT"
if [ ! -d ~/.sns/tmp ]; then
mkdir -p ~/.sns/tmp
fi
fi

echo "$PROD_STR, $VER_STR"
if [ -n "$ERR_NO_SSL" ]; then
echo >&2 "  Warning: OpenSSL not installed. Encryption disabled."
fi
if [ -n "$ERR_NO_KEY" ]; then
echo "  Warning: No encryption key was provided. Encryption disabled."
fi

if [ -n "$ERR_NO_SSL" -o -n "$ERR_NO_KEY" ]; then
pause
fi

#==============================================================================
# End Section: Configuration
#==============================================================================
#==============================================================================
# Section: Argument Parsing
#==============================================================================

NAME=""
NOTEBOOK=""
SECTION=""

if [ -z "$1" ]; then #If no input was given, print help
    help
    exit 20
else #Assume the user wants to do something.
    ARGS=( "$@" )
    for ARG in ${ARGS[@]};do
        if   [  "$ARG" = "-c"   -o  "$ARG" = "--create"    ]; then CREATE="TRUE"
        elif [  "$ARG" = "-d"   -o  "$ARG" = "--delete"    ]; then DELETE="TRUE"
        elif [  "$ARG" = "-e"   -o  "$ARG" = "--edit"      ]; then EDIT="TRUE"
        elif [  "$ARG" = "-ce"  -o  "$ARG" = "-ec"         ]; then EDIT="TRUE";CREATE="TRUE"
        elif [  "$ARG" = "-p"   -o  "$ARG" = "--print"     ]; then PRINT="TRUE"
        elif [  "$ARG" = "-l"   -o  "$ARG" = "--list"      ]; then LIST="TRUE"
        elif [ "$ARG"  = "-h"   -o  "$ARG" == "--help"     ]; then help; exit 0
        elif [ "$ARG"  = "-w"   -o  "$ARG" == "--wconf"    ]; then w_conf; exit
        else
            if [ -z "$NAME" -a -n $ARG ]; then
                NAME=$ARG
            elif [ -z "$NOTEBOOK" -a -n $ARG ]; then
                NOTEBOOK=$ARG
            elif [ -z "$SECTION" -a -n $ARG ]; then
                SECTION=$ARG
            fi
        fi
    done
    if [ -n "$NAME" -a -z "$NOTEBOOK" ]; then
        NOTEBOOK="$NAME"
        NAME=""
    fi
fi

# Note: w_conf has highest priority, and it is the only function that can
# work without any parameters.

#==============================================================================
# End Section: Argument Parsing
#==============================================================================
# Help requires no arguments, and is exclusive.
if [ -n "$HELP" ]; then help; exit 0; fi

# List only requires a notebook, and is exclusive.
if [ -z "$NOTEBOOK" ]; then
    echo "  ERROR: Insufficient arguments:"
    echo "          Notebook not specified"
    exit 30
fi

if [ -n "$LIST" ]; then

    list
    exit 0
fi

#All other functions require a note title and notebook.

if [ -z "$NAME" ]; then
    echo "  ERROR: Insufficient arguments:"
    echo "          Title not specified"
    exit 30
fi

NOTEDIR=$BASEDIR/$NOTEBOOK/$SECTION/
NOTE=$NOTEDIR$NAME.$EXT

if [ "$ENCRYPTION" == "TRUE" ]; then NOTE=$NOTE.enc; fi
if [ "$PRINT"      == "TRUE" ]; then print; exit 0; fi
if [ "$CREATE"     == "TRUE" ]; then create; fi
if [ "$EDIT"       == "TRUE" ]; then edit; fi