package Mnemosyne::Config;
use strict;
use warnings;

# Loads mnemosyne.conf (INI-style) and exposes a simple accessor.
# Usage:
#   my $cfg = Mnemosyne::Config->new('/path/to/mnemosyne.conf');
#   my $token = $cfg->get('bot', 'token');
#   my $href  = $cfg->section('bot');   # all keys in [bot]

sub new {
    my ($class, $path) = @_;
    die "Config file not specified\n"      unless defined $path;
    die "Config file not found: $path\n"   unless -f $path;

    my $self = bless { _path => $path, _data => {} }, $class;
    $self->_parse;
    return $self;
}

sub _parse {
    my ($self) = @_;
    open my $fh, '<', $self->{_path}
        or die "Cannot open config '$self->{_path}': $!\n";

    my $section = '_default';
    while (my $line = <$fh>) {
        chomp $line;
        $line =~ s/\s*#.*$//;   # strip inline comments
        $line =~ s/^\s+|\s+$//g; # trim
        next unless length $line;

        if ($line =~ /^\[(\w+)\]$/) {
            $section = lc $1;
        }
        elsif ($line =~ /^([\w_]+)\s*=\s*(.*)$/) {
            my ($key, $val) = (lc $1, $2);
            $val =~ s/\s+$//;
            $self->{_data}{$section}{$key} = $val;
        }
        else {
            warn "Config: unrecognised line in $self->{_path}: $line\n";
        }
    }
    close $fh;
}

sub get {
    my ($self, $section, $key) = @_;
    $section = lc $section;
    $key     = lc $key;
    return $self->{_data}{$section}{$key};
}

sub section {
    my ($self, $section) = @_;
    return { %{ $self->{_data}{lc $section} // {} } };
}

# Returns the list of allowed chat IDs as an array ref (parsed from the
# comma-separated 'allowed_chat_ids' value in [bot]).
sub allowed_chat_ids {
    my ($self) = @_;
    my $raw = $self->get('bot', 'allowed_chat_ids') // '';
    my @ids = grep { /^\d+$/ } map { s/^\s+|\s+$//gr } split /,/, $raw;
    return \@ids;
}

1;