libgit2: Resolve merge conflict automatically - libgit2

Question

I'm writing a program that is using libgit2 with a repo for management of config files across multiple instances. If there is a conflicting merge I would like to automatically resolve this (by picking the latest commits), without user interaction.
After performing a git_merge I get the git_repository_index and check if git_index_has_conflicts.
When I iterate over the conflicts I am able to get the git_index_entry for the contributing parts, but here is where my basic understanding of git falls short. My approach is to resolve what git_commit that relates to the git_index_entry and check the commit time to determine which entry to pick for merged solution. At the moment I'm a bit stuck on this so any pointers on how to go about doing or if there is a better approach to this problem is much appreciated.
I need to use the libgit2 API to solve this.
Here is some simplified sample code to show my approach:
void merge(const git_a_repository* a_repo, const git_signature* a_signature)
{
//Get the FETCH_HEAD annotated commit
git_annotated_commit* annotated = nullptr;
git_object* obj = nullptr;
git_revparse_single(&obj, a_repo, "FETCH_HEAD");
git_annotated_commit_lookup(annotated, a_repo, git_object_id(obj));
git_object_free(obj);
//Omitting git_merge_analysis for simplicity
//and assuming merge condition
//Merge the FETCH_HEAD with HEAD
git_merge_options merge_opts = GIT_MERGE_OPTIONS_INIT;
git_checkout_options checkout_opts = GIT_CHECKOUT_OPTIONS_INIT;
checkout_opts.checkout_strategy = GIT_CHECKOUT_FORCE
| GIT_CHECKOUT_ALLOW_CONFLICTS;
git_merge(a_repo,(const git_annotated_commit**)(&annotated),
1, &merge_opts, &checkout_opts);
git_index* index = nullptr;
git_a_repository_index(&index, a_repo);
//Handle conflicts
if (git_index_has_conflicts(index))
{
const git_index_entry* ancestor = nullptr;
const git_index_entry* our = nullptr;
const git_index_entry* their = nullptr;
git_index_conflict_iterator* conflicts = nullptr;
int err = 0;
std::vector entriesToKeep;
git_index_conflict_iterator_new(&conflicts, index);
while ((err = git_index_conflict_next(&ancestor, &our, &their, conflicts))
== GIT_OK)
{
git_commit* ourcommit = nullptr;
git_commit* theircommit = nullptr;
//TODO: Need to find the commit belonging to git_index_entry
// to look up the comit time and use this to select
// which git_index_entry should be staged
//entriesToKeep.push_back(selectedEntry);
}
for (auto r : entriesToKeep)
{
git_index_add(index, r);
}
git_index_conflict_iterator_free(conflicts);
git_index_conflict_cleanup(index);
}
//Commit merge
git_tree* tree = nullptr;
git_oid tree_oid, commit_oid;
git_index_write_tree(&tree_oid, index);
git_tree_lookup(&tree, a_repo, &tree_oid);
git_reference* head_ref = nullptr;
git_a_repository_head(&head_ref, a_repo);
git_commit** parents = (git_commit**)(calloc(2, sizeof(git_commit*)));
git_reference_peel((git_object**)&parents[0], head_ref, GIT_OBJECT_COMMIT);
git_commit_lookup(&parents[1], a_repo, git_annotated_commit_id(annotated));
git_commit_create(&commit_oid, a_repo, git_reference_name(head_ref),
a_signature, a_signature, NULL, "Merge", tree, 2,
(const git_commit**)parents);
free(parents);
git_tree_free(tree);
git_annotated_commit_free(annotated);
git_a_repository_state_cleanup(a_repo);
}