+/*
+ Copyright (C) 2023 Carl Hetherington <cth@carlh.net>
+
+ This file is part of DCP-o-matic.
+
+ DCP-o-matic is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2 of the License, or
+ (at your option) any later version.
+
+ DCP-o-matic is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with DCP-o-matic. If not, see <http://www.gnu.org/licenses/>.
+
+*/
+
+
+#include "compose.hpp"
+#include "constants.h"
+#include "dcpomatic_assert.h"
+#include "font_id_allocator.h"
+#include <dcp/reel.h>
+#include <dcp/reel_closed_caption_asset.h>
+#include <dcp/reel_subtitle_asset.h>
+#include <dcp/subtitle_asset.h>
+#include <set>
+#include <string>
+#include <vector>
+
+
+using std::shared_ptr;
+using std::set;
+using std::string;
+using std::vector;
+
+
+void
+FontIDAllocator::add_fonts_from_reels(vector<shared_ptr<dcp::Reel>> const& reels)
+{
+ int reel_index = 0;
+ for (auto reel: reels) {
+ if (auto sub = reel->main_subtitle()) {
+ add_fonts_from_asset(reel_index, sub->asset());
+ }
+
+ for (auto ccap: reel->closed_captions()) {
+ add_fonts_from_asset(reel_index, ccap->asset());
+ }
+
+ ++reel_index;
+ }
+}
+
+
+void
+FontIDAllocator::add_fonts_from_asset(int reel_index, shared_ptr<const dcp::SubtitleAsset> asset)
+{
+ for (auto const& font: asset->font_data()) {
+ _map[Font(reel_index, asset->id(), font.first)] = 0;
+ }
+
+ if (asset->font_data().empty()) {
+ _map[Font(reel_index, asset->id(), "")] = 0;
+ }
+}
+
+
+void
+FontIDAllocator::add_font(int reel_index, string asset_id, string font_id)
+{
+ _map[Font(reel_index, asset_id, font_id)] = 0;
+}
+
+
+void
+FontIDAllocator::allocate()
+{
+ /* Last reel index that we have; i.e. the last prefix number that would be used by "old"
+ * font IDs (i.e. ones before this FontIDAllocator was added and used)
+ */
+ auto const last_reel = std::max_element(
+ _map.begin(),
+ _map.end(),
+ [] (std::pair<Font, int> const& a, std::pair<Font, int> const& b) {
+ return a.first.reel_index < b.first.reel_index;
+ })->first.reel_index;
+
+ /* Number of times each ID has been used */
+ std::map<string, int> used_count;
+
+ for (auto& font: _map) {
+ auto const proposed = String::compose("%1_%2", font.first.reel_index, font.first.font_id);
+ if (used_count.find(proposed) != used_count.end()) {
+ /* This ID was already used; we need to disambiguate it. Do so by using
+ * an ID above last_reel
+ */
+ font.second = last_reel + used_count[proposed];
+ ++used_count[proposed];
+ } else {
+ /* This ID was not yet used */
+ used_count[proposed] = 1;
+ font.second = font.first.reel_index;
+ }
+ }
+}
+
+
+string
+FontIDAllocator::font_id(int reel_index, string asset_id, string font_id) const
+{
+ auto iter = _map.find(Font(reel_index, asset_id, font_id));
+ DCPOMATIC_ASSERT(iter != _map.end());
+ return String::compose("%1_%2", iter->second, font_id);
+}
+