path: root/test/NamespaceReferenceManager.cpp

#include <catch2/catch_test_macros.hpp>

#include "InMemoryBackend.h"
#include "Merkle.h"
#include "NamespaceReferenceManager.h"
#include "ObjectManager.h"

#include <memory>

// ---------------------------------------------------------------------------
// Resolver — two-level reparse through the branch tree.
//
// NamespaceReferenceManager::Resolve rewrites
//   /system/branches/<name>/multigroups/<mg>/<sub>...
// into
//   /system/snapshots/<mg_hash>/<sub>...
// by reading branch.target_hash (a Merkle<string> root) from storage and
// looking up <mg>. Session paths consult the per-session override map first
// and fall back to the global branch when no override is set.
// ---------------------------------------------------------------------------

namespace {

using Path = std::vector<std::string>;

// Pad a label into a deterministic 64-char hex string so the merkle codec can
// decode it as a 32-byte payload.
std::string mk_hash(char c, char d = '0')
{
    std::string h(64, '0');
    h[0] = c;
    h[1] = d;
    return h;
}

std::unique_ptr<nt::ObjectManager::object_type> make_type(OBJECT_TYPE label)
{
    auto t      = std::make_unique<nt::ObjectManager::object_type>();
    t->label    = label;
    t->methods  = { OPEN, CLOSE };
    return t;
}

void register_branch(nt::ObjectManager& om,
                     const std::string& name,
                     const std::string& target_hash)
{
    auto br         = std::make_unique<nt::ObjectManager::Branch>();
    br->name        = name;
    br->target_hash = target_hash;
    om.Register({"system", "branches", name}, std::move(br), make_type(BRANCH));
}

void register_session(nt::ObjectManager& om,
                      const std::string& id,
                      std::map<std::string, std::string> overrides = {})
{
    auto s = std::make_unique<nt::ObjectManager::Session>();
    s->branch_overrides = std::move(overrides);
    om.Register({"system", "sessions", id}, std::move(s), make_type(SESSION));
}

// Builds a branch tree with a single (mg_name → mg_hash) entry. Returns the
// branch-tree root hex.
std::string build_branch_tree(nt::InMemoryBackend& store,
                               const std::string& mg_name,
                               const std::string& mg_hash_hex)
{
    return nt::Merkle<std::string>::Insert(store, "", mg_name,
                                            nt::hex_to_bin(mg_hash_hex));
}

}  // namespace

TEST_CASE("Branch sub-path rewrites through the branch tree to the mg snapshot",
          "[resolve]")
{
    nt::ObjectManager om;
    nt::InMemoryBackend store;

    const std::string mg_hash = mk_hash('a');
    const std::string tree    = build_branch_tree(store, "warehouse", mg_hash);
    register_branch(om, "main", tree);

    nt::NamespaceReferenceManager nrm(om, store);
    REQUIRE(nrm.Resolve({"system", "branches", "main", "multigroups", "warehouse", "relations", "items"})
            == Path{"system", "snapshots", mg_hash, "relations", "items"});
}

TEST_CASE("Resolve on the branch object itself is left unchanged", "[resolve]")
{
    nt::ObjectManager om;
    nt::InMemoryBackend store;
    const std::string tree = build_branch_tree(store, "warehouse", mk_hash('a'));
    register_branch(om, "main", tree);

    nt::NamespaceReferenceManager nrm(om, store);
    const Path p{"system", "branches", "main"};
    REQUIRE(nrm.Resolve(p) == p);
}

TEST_CASE("Resolve on an unborn branch leaves the path unchanged", "[resolve]")
{
    nt::ObjectManager om;
    nt::InMemoryBackend store;
    register_branch(om, "main", "");  // unborn

    nt::NamespaceReferenceManager nrm(om, store);
    const Path p{"system", "branches", "main", "multigroups", "warehouse", "relations", "items"};
    REQUIRE(nrm.Resolve(p) == p);
}

TEST_CASE("Resolve on an absent multigroup leaves the path unchanged", "[resolve]")
{
    nt::ObjectManager om;
    nt::InMemoryBackend store;
    const std::string tree = build_branch_tree(store, "warehouse", mk_hash('a'));
    register_branch(om, "main", tree);

    nt::NamespaceReferenceManager nrm(om, store);
    const Path p{"system", "branches", "main", "multigroups", "audit", "relations", "events"};
    REQUIRE(nrm.Resolve(p) == p);
}

TEST_CASE("Resolve on an unknown branch leaves the path unchanged", "[resolve]")
{
    nt::ObjectManager om;
    nt::InMemoryBackend store;
    nt::NamespaceReferenceManager nrm(om, store);
    const Path p{"system", "branches", "ghost", "multigroups", "warehouse", "relations", "items"};
    REQUIRE(nrm.Resolve(p) == p);
}

TEST_CASE("Non-branch paths pass through unchanged", "[resolve]")
{
    nt::ObjectManager om;
    nt::InMemoryBackend store;
    nt::NamespaceReferenceManager nrm(om, store);
    const Path p{"relations", "anywhere"};
    REQUIRE(nrm.Resolve(p) == p);
}

TEST_CASE("Session override takes precedence over the global branch HEAD",
          "[resolve]")
{
    nt::ObjectManager om;
    nt::InMemoryBackend store;

    const std::string mg_global  = mk_hash('a');
    const std::string mg_session = mk_hash('b');
    const std::string tree_global  =
        build_branch_tree(store, "warehouse", mg_global);
    const std::string tree_session =
        build_branch_tree(store, "warehouse", mg_session);

    register_branch(om, "main", tree_global);
    register_session(om, "sess123", {{"main", tree_session}});

    nt::NamespaceReferenceManager nrm(om, store);
    REQUIRE(nrm.Resolve({"system", "sessions", "sess123", "branches", "main",
                         "multigroups", "warehouse", "relations", "items"})
            == Path{"system", "snapshots", mg_session, "relations", "items"});
}

TEST_CASE("Session resolution falls back to global branch when override is absent",
          "[resolve]")
{
    nt::ObjectManager om;
    nt::InMemoryBackend store;

    const std::string mg_global = mk_hash('a');
    const std::string tree_global =
        build_branch_tree(store, "warehouse", mg_global);

    register_branch(om, "main", tree_global);
    register_session(om, "sess123");  // no overrides

    nt::NamespaceReferenceManager nrm(om, store);
    REQUIRE(nrm.Resolve({"system", "sessions", "sess123", "branches", "main",
                         "multigroups", "warehouse", "relations", "items"})
            == Path{"system", "snapshots", mg_global, "relations", "items"});
}

TEST_CASE("Session resolution with neither override nor global branch is unchanged",
          "[resolve]")
{
    nt::ObjectManager om;
    nt::InMemoryBackend store;
    register_session(om, "sess123");

    nt::NamespaceReferenceManager nrm(om, store);
    const Path p{"system", "sessions", "sess123", "branches", "main",
                 "multigroups", "warehouse", "relations", "items"};
    REQUIRE(nrm.Resolve(p) == p);
}

TEST_CASE("Empty input path is returned unchanged", "[resolve]")
{
    nt::ObjectManager om;
    nt::InMemoryBackend store;
    nt::NamespaceReferenceManager nrm(om, store);
    REQUIRE(nrm.Resolve({}).empty());
}