From 091598000c8dee1a348402c677d3892a1581f424 Mon Sep 17 00:00:00 2001
From: Thomas Lamprecht <t.lamprecht@proxmox.com>
Date: Mon, 21 Nov 2022 08:09:24 +0100
Subject: [PATCH] tag helpers: add get_unique_tags method for filtering out
 duplicates

tags must be unique, allow the user some control in how unique (case
sensitive) and honor the ordering settings (even if I doubt any
production setups wants to spent time and $$$ on cautiously
reordering all tags of their dozens to hundreds virtual guests..

Have some duplicate code to avoid checking to much in the loop
itself, as frequent branches can be more expensive.

Signed-off-by: Thomas Lamprecht <t.lamprecht@proxmox.com>
---
 src/PVE/GuestHelpers.pm | 31 +++++++++++++++++++++++++++++++
 1 file changed, 31 insertions(+)

diff --git a/src/PVE/GuestHelpers.pm b/src/PVE/GuestHelpers.pm
index 98cfbf8..b4ccbaa 100644
--- a/src/PVE/GuestHelpers.pm
+++ b/src/PVE/GuestHelpers.pm
@@ -335,4 +335,35 @@ sub assert_tag_permissions {
     }
 }
 
+sub get_unique_tags {
+    my ($tags, $no_join_result) = @_;
+
+    $tags = [ split_list($tags // '') ] if ref($tags) ne 'ARRAY';
+    return !$no_join_result ? '': [] if !scalar($tags->@*);
+
+    my $datacenter_config = PVE::Cluster::cfs_read_file('datacenter.cfg');
+    my $tag_style_config = $datacenter_config->{'tag-style'} // {};
+    my $case_sensitive = !!$tag_style_config->{'case-sensitive'};
+
+    my $seen_tags = {};
+    my $res = [];
+    if (!defined($tag_style_config->{ordering}) || $tag_style_config->{ordering} ne 'config') {
+	for my $tag ( sort { $case_sensitive ? $a cmp $b : lc($a) cmp lc($b) } $tags->@*) {
+	    $tag = lc($tag) if !$case_sensitive;
+	    next if $seen_tags->{$tag};
+	    $seen_tags->{$tag} = 1;
+	    push @$res, $tag;
+	}
+    } else {
+	for my $tag ($tags->@*) {
+	    $tag = lc($tag) if !$case_sensitive;
+	    next if $seen_tags->{$tag};
+	    $seen_tags->{$tag} = 1;
+	    push @$res, $tag;
+	}
+    }
+
+    return !$no_join_result ? join(';', $res->@*) : $res;
+}
+
 1;