feat(opds): Allow selecting the download format

When downloading a book via OPDS, the last acquisition link is chosen when there are multiple. This allows choosing which format to download when there are many. Having only one format will automatically download that.
2026-04-19 23:15:54 -04:00
parent c38013aac3
commit 1986092522
12 changed files with 941 additions and 14 deletions
@@ -0,0 +1,122 @@
+#include "OpdsFormatLabel.h"
+
+#include <algorithm>
+#include <iterator>
+
+#include "util/UrlUtils.h"
+
+namespace {
+bool hasDuplicateFormatKey(const OpdsAcquisitionLink& acquisition,
+                           const std::vector<OpdsAcquisitionLink>& acquisitionLinks) {
+  size_t sameFormatCount = 0;
+  for (const auto& link : acquisitionLinks) {
+    if (link.formatKey == acquisition.formatKey) {
+      sameFormatCount++;
+      if (sameFormatCount > 1) {
+        return true;
+      }
+    }
+  }
+
+  return false;
+}
+
+std::string resolvedHostname(const OpdsAcquisitionLink& acquisition, const std::string& serverUrl) {
+  const std::string resolvedUrl =
+      acquisition.href.rfind("http", 0) == 0 ? acquisition.href : UrlUtils::buildUrl(serverUrl, acquisition.href);
+  return UrlUtils::extractHostname(resolvedUrl);
+}
+
+std::vector<std::string> resolvedHostnames(const std::vector<OpdsAcquisitionLink>& acquisitionLinks,
+                                           const std::string& serverUrl) {
+  std::vector<std::string> hostnames;
+  hostnames.reserve(acquisitionLinks.size());
+  std::transform(acquisitionLinks.begin(), acquisitionLinks.end(), std::back_inserter(hostnames),
+                 [&serverUrl](const OpdsAcquisitionLink& link) { return resolvedHostname(link, serverUrl); });
+  return hostnames;
+}
+
+std::string buildDuplicateAwareLabel(const OpdsAcquisitionLink& acquisition,
+                                     const std::vector<OpdsAcquisitionLink>& acquisitionLinks,
+                                     const std::vector<std::string>& hostnames, const size_t currentIndex) {
+  std::string label = opdsBaseFormatLabel(acquisition);
+  if (!hasDuplicateFormatKey(acquisition, acquisitionLinks)) {
+    return label;
+  }
+
+  const std::string& hostname = hostnames[currentIndex];
+  if (hostname.empty()) {
+    return label;
+  }
+
+  label.reserve(label.size() + hostname.size() + 8);
+  label += " - ";
+  label += hostname;
+
+  size_t duplicateCount = 0;
+  size_t duplicateIndex = 0;
+  for (size_t i = 0; i < acquisitionLinks.size(); i++) {
+    if (acquisitionLinks[i].formatKey == acquisition.formatKey && hostnames[i] == hostname) {
+      duplicateCount++;
+      if (i <= currentIndex) {
+        duplicateIndex++;
+      }
+    }
+  }
+
+  if (duplicateCount > 1) {
+    label += " (";
+    label += std::to_string(duplicateIndex);
+    label += ")";
+  }
+
+  return label;
+}
+}  // namespace
+
+const char* opdsBaseFormatLabel(const OpdsAcquisitionLink& acquisition) {
+  if (acquisition.formatKey == "kepub") {
+    return "KEPUB";
+  }
+  if (acquisition.formatKey == "epub") {
+    return "EPUB";
+  }
+  if (acquisition.formatKey == "txt") {
+    return "TXT";
+  }
+  if (acquisition.formatKey == "md") {
+    return "MD";
+  }
+  if (acquisition.formatKey == "xtc") {
+    return "XTC";
+  }
+  if (acquisition.formatKey == "xtch") {
+    return "XTCH";
+  }
+
+  return "";
+}
+
+std::string opdsFormatSelectionLabel(const OpdsAcquisitionLink& acquisition,
+                                     const std::vector<OpdsAcquisitionLink>& acquisitionLinks,
+                                     const std::string& serverUrl) {
+  const auto hostnames = resolvedHostnames(acquisitionLinks, serverUrl);
+  for (size_t i = 0; i < acquisitionLinks.size(); i++) {
+    if (acquisitionLinks[i].href == acquisition.href && acquisitionLinks[i].formatKey == acquisition.formatKey) {
+      return buildDuplicateAwareLabel(acquisition, acquisitionLinks, hostnames, i);
+    }
+  }
+
+  return opdsBaseFormatLabel(acquisition);
+}
+
+std::vector<std::string> buildOpdsFormatSelectionLabels(const std::vector<OpdsAcquisitionLink>& acquisitionLinks,
+                                                        const std::string& serverUrl) {
+  const auto hostnames = resolvedHostnames(acquisitionLinks, serverUrl);
+  std::vector<std::string> labels;
+  labels.reserve(acquisitionLinks.size());
+  for (size_t i = 0; i < acquisitionLinks.size(); i++) {
+    labels.push_back(buildDuplicateAwareLabel(acquisitionLinks[i], acquisitionLinks, hostnames, i));
+  }
+  return labels;
+}