#!/usr/bin/perl

use strict;

my $ref_values;
my $ref_names;

### Database file
my $db_file = './phone.txt' || $ARGV[1];

### Field eparator
my $separator = '#' || $ARGV[2];

### Set the primary key
my $pri = 1 || $ARGV[3];

my $primary = $pri - 1;

my $keyword = $ARGV[0] || die
    qq(     \n),
    qq(use: agenda keyword (databasefile separator pos.key)\n),
    qq(     \n),
    qq(     default database:  $db_file\n),
    qq(     default separator: $separator\n),
    qq(     default pos.key:   $pri\n),
    qq(     \n),
    qq(     examples of use:\n),
    qq(     agenda smith  (shows all '*smith*' in field 'pos.key')\n),
    qq(     agenda .      (shows  all records)\n),
    qq(     \n),
    qq(     To create a database, edit a text file writing in the first\n),
    qq(     line the names of the fields, separated by some *separator*\n),
    qq(     ('#' for example), and related entries in the following records\n),
    qq(     \n);

### Load the variables
($ref_values,$ref_names) = db_read($db_file, $separator, $primary);


### Print the database content
db_print($ref_values,$ref_names,$keyword);
############
sub db_read{
############

###
### This routine reads the content of an ASCII database
### with field names as first record, storing the content
### into an hash of arrays.
###
###

    use strict;

    my $db_file = shift();    ### database file name
    my $separator = shift();  ### field separator
    my $primary = shift();    ### primary key

    my %values;
    my @fields;
    my @names;
    my $i;

### Open the database for reading
    open DB, "<$db_file" or die "Can't open $db_file: $!\n";

### Read the first record containing the names of the fields
    my $first_record = <DB>;

### Remove the newline
    chomp $first_record;

### Split the record to get the field names
    @names = split($separator,$first_record);

### Now read the rest of the file and store
### the records into an hash of arrays

    while (<DB>) {

### Remove the new line character at end of record
        chomp;
### Split the record into fields
        @fields = split /$separator/;

### Populate the hashes defined by the fields in $first_record
        foreach $i (0..$#names-1) {
           $values{$fields[$primary]}[$i] = $fields[$i];
        }
    }

### Close database
    close DB;

### Return the the reference to the hash of arrays
### and the array of field names
    return (\%values,\@names);

}

#############
sub db_print{
#############

###
### This routine prints the content of an hash of arrays
### sorted by its keys. The hash of arrays is created by
### db_read subruotine.
###

    use strict;

    my %values = %{ shift() };
    my @names = @{ shift() };
    my $keyword = shift();

    my $item;
    my $features;

    for $item ( sort keys %values ) {

### Scan the hash of arrays searching for $keyword

         my $found = 0;
         for $features (0..$#names-1) {
             if ($item =~ /$keyword/i or
                 $values{$item}[$features]=~ /$keyword/i) {
                 $found = 1;
             }
         }
### Print the hash of arrays if anything was found

         if ($found) {
             printf qq(\n ** keyword: %s\n\n), $item;
             for $features (0..$#names-1) {
                 printf qq(    %s = %s\n), $names[$features],
                                           $values{$item}[$features];
             }
             $found = -1;
         }
    }

}