1 files changed, 80 insertions, 0 deletions
diff --git a/src/tangara/database/file_gatherer.cpp b/src/tangara/database/file_gatherer.cpp
new file mode 100644
index 00000000..b7b7271e
--- /dev/null
+++ b/src/tangara/database/file_gatherer.cpp
@@ -0,0 +1,80 @@
+/*
+ * Copyright 2023 jacqueline <me@jacqueline.id.au>
+ *
+ * SPDX-License-Identifier: GPL-3.0-only
+ */
+
+#include "file_gatherer.hpp"
+
+#include <deque>
+#include <functional>
+#include <sstream>
+#include <string>
+
+#include "ff.h"
+
+#include "memory_resource.hpp"
+#include "spi.hpp"
+
+namespace database {
+
+static_assert(sizeof(TCHAR) == sizeof(char), "TCHAR must be CHAR");
+
+auto FileGathererImpl::FindFiles(
+    const std::string& root,
+    std::function<void(std::string_view, const FILINFO&)> cb) -> void {
+  std::pmr::deque<std::pmr::string> to_explore{&memory::kSpiRamResource};
+  to_explore.push_back({root.data(), root.size()});
+
+  while (!to_explore.empty()) {
+    auto next_path_str = to_explore.front();
+    to_explore.pop_front();
+
+    const TCHAR* next_path = static_cast<const TCHAR*>(next_path_str.c_str());
+
+    FF_DIR dir;
+    FRESULT res;
+    {
+      auto lock = drivers::acquire_spi();
+      res = f_opendir(&dir, next_path);
+    }
+    if (res != FR_OK) {
+      // TODO: log.
+      continue;
+    }
+
+    for (;;) {
+      FILINFO info;
+      {
+        auto lock = drivers::acquire_spi();
+        res = f_readdir(&dir, &info);
+      }
+      if (res != FR_OK || info.fname[0] == 0) {
+        // No more files in the directory.
+        break;
+      } else if (info.fattrib & (AM_HID | AM_SYS) || info.fname[0] == '.') {
+        // System or hidden file. Ignore it and move on.
+        continue;
+      } else {
+        std::pmr::string full_path{&memory::kSpiRamResource};
+        full_path += next_path_str;
+        full_path += "/";
+        full_path += info.fname;
+
+        if (info.fattrib & AM_DIR) {
+          // This is a directory. Add it to the explore queue.
+          to_explore.push_back(full_path);
+        } else {
+          // This is a file! Let the callback know about it.
+          // std::invoke(cb, full_path.str(), info);
+          std::invoke(cb, full_path, info);
+        }
+      }
+    }
+
+    auto lock = drivers::acquire_spi();
+    f_closedir(&dir);
+  }
+}
+
+}  // namespace database