#!/bin/bash
# vi:set ts=8 sw=4 et sta:
#
# Author: Clark J. Wang <dearvoid at gmail.com>
# 
# $Date$
# $HeadURL$
# $Revision$
#
#--------------------------------------------------------------------#

function BEGIN
{
    export record_file=records
    add_file=add
    delete_file=delete
    exit_if_file_not_found "$record_file" "$add_file" "$delete_file"
}

#--------------------------------------------------------------------#

function exit_if_file_not_found
{
    local file=
    while [ $# -gt 0 ]; do
        file=$1
        shift
        if [ ! -e "$file" ]; then
            echo "Required file '$file' does not exist."
            exit 1
        fi
    done
}

#--------------------------------------------------------------------#

function wait_enter_with_msg
{
    local msg=$1
    echo -en "$msg"
    read
}

#--------------------------------------------------------------------#

function print_all_records
{
    sed -e 's/:/ /g' "$record_file"
}

#--------------------------------------------------------------------#

function print_all_records_formatted
{
    awk '
BEGIN { FS = ":"; }
{ printf "%-10s %-10s %-5s %s %-3s %-20s %s\n", $2, $3, $4, $1, $5, $6, $7; }
' $record_file | sort
}

#--------------------------------------------------------------------#

function print_names_and_phone
{
    awk 'BEGIN { FS = ":"; } { printf "%s,%s,%s\n", $2, $3, $1; }' $record_file
}

#--------------------------------------------------------------------#

function print_names_and_phone_formatted
{
    awk 'BEGIN { FS = ":"; } { printf "%-10s %-10s %s\n", $2, $3, $1; }' $record_file
}

#--------------------------------------------------------------------#

function search_by_name
{
    local keyword=
    while true; do
        echo -n "Enter keyword: "
        read keyword
        if [ ! "$keyword" ]; then
            echo "keyword not entered"
            continue
        fi

        if ! grep -i "$keyword" $record_file 2> /dev/null; then
            echo "$keyword not found"
        fi

        return
    done
}

#--------------------------------------------------------------------#

function display_main_menu
{
    clear

    cat << END
Employees Info Main Menu
========================

1 - Print All Current Records
2 - Print All Current Records (formatted)
3 - Print Names and Phone Numbers
4 - Print Names and Phone Numbers (formatted)
5 - Search for specific Record(s)
6 - Add New Records
7 - Delete Records

Q - Quit

END
    echo -n "Your Selection: "
}

#--------------------------------------------------------------------#

function END
{
    exit 0
}

#-- main ------------------------------------------------------------#

{
    BEGIN

    while true; do
        display_main_menu
        read user_selection
        case "$user_selection" in
            1)
            {
                print_all_records
                wait_enter_with_msg "\nPress Enter to continue..."
            };;

            2)
            {
                print_all_records_formatted
                wait_enter_with_msg "\nPress Enter to continue..."
            };;

            3)
            {
                print_names_and_phone
                wait_enter_with_msg "\nPress Enter to continue..."
            };;

            4)
            {
                print_names_and_phone_formatted
                wait_enter_with_msg "\nPress Enter to continue..."
            };;

            5)
            {
                search_by_name
                wait_enter_with_msg "\nPress Enter to continue..."
            };;

            6)
            {
                ./$add_file
            };;

            7)
            {
                ./$delete_file
            };;

            q|Q)
            {
                END
            };;

            "")
            {
                wait_enter_with_msg "Selection not entered. Press Enter to continue..."
            };;

            *)
            {
                wait_enter_with_msg "Invalid code! Press Enter to continue..."
            };;
        esac
    done

    END
}