lookForGridInfo(): make it work properly when passed the old PROJ name

Fixes https://github.com/qgis/QGIS/issues/45470

That is, if the file for the old PROJ name is not found, but the file
for the new PROJ name is found, then use the later for fullFilename and
gridAvailable.

1 files changed, 25 insertions, 1 deletions

diff --git a/src/iso19111/factory.cpp b/src/iso19111/factory.cpp
index 3088f468..52c3f82b 100644
--- a/src/iso19111/factory.cpp
+++ b/src/iso19111/factory.cpp
@@ -3272,7 +3272,9 @@ bool DatabaseContext::lookForGridInfo(
                "grid_alternatives.open_license, "
                "grid_packages.open_license AS package_open_license, "
                "grid_alternatives.direct_download, "
-               "grid_packages.direct_download AS package_direct_download "
+               "grid_packages.direct_download AS package_direct_download, "
+               "grid_alternatives.proj_grid_name, "
+               "grid_alternatives.old_proj_grid_name "
                "FROM grid_alternatives "
                "LEFT JOIN grid_packages ON "
                "grid_alternatives.package_name = grid_packages.package_name "
@@ -3286,6 +3288,28 @@ bool DatabaseContext::lookForGridInfo(
         openLicense = (row[3].empty() ? row[4] : row[3]) == "1";
         directDownload = (row[5].empty() ? row[6] : row[5]) == "1";
 
+        const auto &proj_grid_name = row[7];
+        const auto &old_proj_grid_name = row[8];
+        if (proj_grid_name != old_proj_grid_name &&
+            old_proj_grid_name == projFilename) {
+            std::string fullFilenameNewName;
+            fullFilenameNewName.resize(2048);
+            if (d->pjCtxt() == nullptr) {
+                d->setPjCtxt(pj_get_default_ctx());
+            }
+            int errno_before = proj_context_errno(d->pjCtxt());
+            bool gridAvailableWithNewName =
+                pj_find_file(d->pjCtxt(), proj_grid_name.c_str(),
+                             &fullFilenameNewName[0],
+                             fullFilenameNewName.size() - 1) != 0;
+            proj_context_errno_set(d->pjCtxt(), errno_before);
+            fullFilenameNewName.resize(strlen(fullFilenameNewName.c_str()));
+            if (gridAvailableWithNewName) {
+                gridAvailable = true;
+                fullFilename = fullFilenameNewName;
+            }
+        }
+
         if (considerKnownGridsAsAvailable &&
             (!packageName.empty() || (!url.empty() && openLicense))) {
             gridAvailable = true;