/*
 * Copyright 2010-2024 The pygit2 contributors
 *
 * This file is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License, version 2,
 * as published by the Free Software Foundation.
 *
 * In addition to the permissions in the GNU General Public License,
 * the authors give you unlimited permission to link the compiled
 * version of this file into combinations with other programs,
 * and to distribute those combinations without any restriction
 * coming from the use of this file.  (The General Public License
 * restrictions do apply in other respects; for example, they cover
 * modification of the file, and distribution when not linked into
 * a combined executable.)
 *
 * This file is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; see the file COPYING.  If not, write to
 * the Free Software Foundation, 51 Franklin Street, Fifth Floor,
 * Boston, MA 02110-1301, USA.
 */

#define PY_SSIZE_T_CLEAN
#include <Python.h>

#include <git2.h>
#include <git2/sys/filter.h>
#include "error.h"
#include "types.h"
#include "utils.h"
#include "repository.h"
#include "oid.h"
#include "options.h"
#include "filter.h"

PyObject *GitError;
PyObject *AlreadyExistsError;
PyObject *InvalidSpecError;

PyObject *DeltaStatusEnum;
PyObject *DiffFlagEnum;
PyObject *FileModeEnum;
PyObject *FileStatusEnum;
PyObject *MergeAnalysisEnum;
PyObject *MergePreferenceEnum;
PyObject *ReferenceTypeEnum;

extern PyTypeObject RepositoryType;
extern PyTypeObject OdbType;
extern PyTypeObject OdbBackendType;
extern PyTypeObject OdbBackendPackType;
extern PyTypeObject OdbBackendLooseType;
extern PyTypeObject OidType;
extern PyTypeObject ObjectType;
extern PyTypeObject CommitType;
extern PyTypeObject DiffType;
extern PyTypeObject DeltasIterType;
extern PyTypeObject DiffIterType;
extern PyTypeObject DiffDeltaType;
extern PyTypeObject DiffFileType;
extern PyTypeObject DiffHunkType;
extern PyTypeObject DiffLineType;
extern PyTypeObject DiffStatsType;
extern PyTypeObject PatchType;
extern PyTypeObject TreeType;
extern PyTypeObject TreeBuilderType;
extern PyTypeObject TreeIterType;
extern PyTypeObject BlobType;
extern PyTypeObject TagType;
extern PyTypeObject WalkerType;
extern PyTypeObject RefdbType;
extern PyTypeObject RefdbBackendType;
extern PyTypeObject RefdbFsBackendType;
extern PyTypeObject ReferenceType;
extern PyTypeObject RevSpecType;
extern PyTypeObject RefLogIterType;
extern PyTypeObject RefLogEntryType;
extern PyTypeObject BranchType;
extern PyTypeObject SignatureType;
extern PyTypeObject RemoteType;
extern PyTypeObject RefspecType;
extern PyTypeObject NoteType;
extern PyTypeObject NoteIterType;
extern PyTypeObject WorktreeType;
extern PyTypeObject MailmapType;
extern PyTypeObject StashType;
extern PyTypeObject RefsIteratorType;
extern PyTypeObject FilterSourceType;


PyDoc_STRVAR(discover_repository__doc__,
  "discover_repository(path: str, across_fs: bool = False[, ceiling_dirs: str]) -> str\n"
  "\n"
  "Look for a git repository and return its path. If not found returns None.");

PyObject *
discover_repository(PyObject *self, PyObject *args)
{
    git_buf repo_path = {NULL};
    const char *path = NULL;
    PyBytesObject *py_path = NULL;
    int across_fs = 0;
    PyBytesObject *py_ceiling_dirs = NULL;
    const char *ceiling_dirs = NULL;
    PyObject *py_repo_path = NULL;
    int err;
    PyObject *result = NULL;

    if (!PyArg_ParseTuple(args, "O&|IO&", PyUnicode_FSConverter, &py_path, &across_fs,
                          PyUnicode_FSConverter, &py_ceiling_dirs))
        return NULL;

    if (py_path != NULL)
        path = PyBytes_AS_STRING(py_path);
    if (py_ceiling_dirs != NULL)
        ceiling_dirs = PyBytes_AS_STRING(py_ceiling_dirs);

    memset(&repo_path, 0, sizeof(git_buf));
    err = git_repository_discover(&repo_path, path, across_fs, ceiling_dirs);

    if (err == GIT_OK) {
        py_repo_path = PyUnicode_DecodeFSDefault(repo_path.ptr);
        git_buf_dispose(&repo_path);
        result = py_repo_path;
    } else if (err == GIT_ENOTFOUND) {
        result = Py_None;
    } else {
        result = Error_set_str(err, path);
    }

    Py_XDECREF(py_ceiling_dirs);
    Py_XDECREF(py_path);

    return result;
};

PyDoc_STRVAR(hashfile__doc__,
    "hashfile(path: str) -> Oid\n"
    "\n"
    "Returns the oid of a new blob from a file path without actually writing\n"
    "to the odb.");
PyObject *
hashfile(PyObject *self, PyObject *args)
{
    git_oid oid;
    PyBytesObject *py_path = NULL;
    const char* path = NULL;
    int err;

    if (!PyArg_ParseTuple(args, "O&", PyUnicode_FSConverter, &py_path))
        return NULL;

    if (py_path != NULL)
        path = PyBytes_AS_STRING(py_path);

    err = git_odb_hashfile(&oid, path, GIT_OBJECT_BLOB);
    Py_XDECREF(py_path);
    if (err < 0)
        return Error_set(err);

    return git_oid_to_python(&oid);
}

PyDoc_STRVAR(hash__doc__,
    "hash(data: bytes) -> Oid\n"
    "\n"
    "Returns the oid of a new blob from a string without actually writing to\n"
    "the odb.");
PyObject *
hash(PyObject *self, PyObject *args)
{
    git_oid oid;
    const char *data;
    Py_ssize_t size;
    int err;

    if (!PyArg_ParseTuple(args, "s#", &data, &size))
        return NULL;

    err = git_odb_hash(&oid, data, size, GIT_OBJECT_BLOB);
    if (err < 0) {
        return Error_set(err);
    }

    return git_oid_to_python(&oid);
}


PyDoc_STRVAR(init_file_backend__doc__,
  "init_file_backend(path: str, flags: int = 0) -> object\n"
  "\n"
  "Open repo backend given path.");
PyObject *
init_file_backend(PyObject *self, PyObject *args)
{
    PyBytesObject *py_path = NULL;
    const char* path = NULL;
    unsigned int flags = 0;
    int err = GIT_OK;
    git_repository *repository = NULL;
    PyObject *result = NULL;

    if (!PyArg_ParseTuple(args, "O&|I", PyUnicode_FSConverter, &py_path, &flags))
        return NULL;
    if (py_path != NULL)
        path = PyBytes_AS_STRING(py_path);

    err = git_repository_open_ext(&repository, path, flags, NULL);

    if (err == GIT_OK) {
        result = PyCapsule_New(repository, "backend", NULL);
    } else {
        result = NULL;
        Error_set_str(err, path);

        if (repository) {
            git_repository_free(repository);
        }

        if (err == GIT_ENOTFOUND) {
            PyErr_Format(GitError, "Repository not found at %s", path);
        }
    }

    Py_XDECREF(py_path);
    return result;
}


PyDoc_STRVAR(reference_is_valid_name__doc__,
    "reference_is_valid_name(refname: str) -> bool\n"
    "\n"
    "Check if the passed string is a valid reference name.");
PyObject *
reference_is_valid_name(PyObject *self, PyObject *py_refname)
{
    const char *refname = pgit_borrow(py_refname);
    if (refname == NULL)
        return NULL;

    int result = git_reference_is_valid_name(refname);
    return PyBool_FromLong(result);
}


PyDoc_STRVAR(tree_entry_cmp__doc__,
    "tree_entry_cmp(a: Object, b: Object) -> int\n"
    "\n"
    "Rich comparison for objects, only available when the objects have been\n"
    "obtained through a tree. The sort criteria is the one Git uses to sort\n"
    "tree entries in a tree object. This function wraps git_tree_entry_cmp.\n"
    "\n"
    "Returns < 0 if a is before b, > 0 if a is after b, and 0 if a and b are\n"
    "the same.");

PyObject *
tree_entry_cmp(PyObject *self, PyObject *args)
{
    Object *a, *b;
    int cmp;

    if (!PyArg_ParseTuple(args, "O!O!", &ObjectType, &a, &ObjectType, &b))
        return NULL;

    if (a->entry == NULL || b->entry == NULL) {
        PyErr_SetString(PyExc_ValueError, "objects lack entry information");
        return NULL;
    }

    cmp = git_tree_entry_cmp(a->entry, b->entry);
    return PyLong_FromLong(cmp);
}

PyDoc_STRVAR(filter_register__doc__,
    "filter_register(name: str, filter_cls: Type[Filter], [priority: int = C.GIT_FILTER_DRIVER_PRIORITY]) -> None\n"
    "\n"
    "Register a filter under the given name.\n"
    "\n"
    "Filters will be run in order of `priority` on smudge (to workdir) and in\n"
    "reverse order of priority on clean (to odb).\n"
    "\n"
    "Two filters are preregistered with libgit2:\n"
    "    - GIT_FILTER_CRLF with priority 0\n"
    "    - GIT_FILTER_IDENT with priority 100\n"
    "\n"
    "`priority` defaults to GIT_FILTER_DRIVER_PRIORITY which imitates a core\n"
    "Git filter driver that will be run last on checkout (smudge) and first \n"
    "on checkin (clean).\n"
    "\n"
    "Note that the filter registry is not thread safe. Any registering or\n"
    "deregistering of filters should be done outside of any possible usage\n"
    "of the filters.\n");

PyObject *
filter_register(PyObject *self, PyObject *args, PyObject *kwds)
{
    const char *name;
    Py_ssize_t size;
    PyObject *py_filter_cls;
    int priority = GIT_FILTER_DRIVER_PRIORITY;
    char *keywords[] = {"name", "filter_cls", "priority", NULL};
    pygit2_filter *filter;
    PyObject *py_attrs;
    PyObject *result = Py_None;
    int err;

    if (!PyArg_ParseTupleAndKeywords(args, kwds, "s#O|i", keywords,
                                     &name, &size, &py_filter_cls, &priority))
        return NULL;

    py_attrs = PyObject_GetAttrString(py_filter_cls, "attributes");
    if (py_attrs == NULL)
        return NULL;

    filter = malloc(sizeof(pygit2_filter));
    if (filter == NULL)
    {
        return PyExc_MemoryError;
    }
    memset(filter, 0, sizeof(pygit2_filter));
    git_filter_init(&filter->filter, GIT_FILTER_VERSION);

    filter->filter.attributes = PyUnicode_AsUTF8(py_attrs);
    filter->filter.shutdown = pygit2_filter_shutdown;
    filter->filter.check = pygit2_filter_check;
    filter->filter.stream = pygit2_filter_stream;
    filter->filter.cleanup = pygit2_filter_cleanup;
    filter->py_filter_cls = py_filter_cls;
    Py_INCREF(py_filter_cls);

    if ((err = git_filter_register(name, &filter->filter, priority)) < 0)
        goto error;

    goto done;

error:
    Py_DECREF(py_filter_cls);
    free(filter);
done:
    Py_DECREF(py_attrs);
    return result;
}

PyDoc_STRVAR(filter_unregister__doc__,
    "filter_unregister(name: str) -> None\n"
    "\n"
    "Unregister the given filter.\n"
    "\n"
    "Note that the filter registry is not thread safe. Any registering or\n"
    "deregistering of filters should be done outside of any possible usage\n"
    "of the filters.\n");

PyObject *
filter_unregister(PyObject *self, PyObject *args)
{
    const char *name;
    Py_ssize_t size;
    int err;

    if (!PyArg_ParseTuple(args, "s#", &name, &size))
        return NULL;
    if ((err = git_filter_unregister(name)) < 0)
        return Error_set(err);

    Py_RETURN_NONE;
}


static void
forget_enums(void)
{
    Py_CLEAR(DeltaStatusEnum);
    Py_CLEAR(DiffFlagEnum);
    Py_CLEAR(FileModeEnum);
    Py_CLEAR(FileStatusEnum);
    Py_CLEAR(MergeAnalysisEnum);
    Py_CLEAR(MergePreferenceEnum);
    Py_CLEAR(ReferenceTypeEnum);
}

PyDoc_STRVAR(_cache_enums__doc__,
    "_cache_enums()\n"
    "\n"
    "For internal use only. Do not call this from user code.\n"
    "\n"
    "Let the _pygit2 C module cache references to Python enums\n"
    "defined in pygit2.enums.\n");

PyObject *
_cache_enums(PyObject *self, PyObject *args)
{
    (void) args;

    /* In case this is somehow being called several times, let go of old references */
    forget_enums();

    PyObject *enums = PyImport_ImportModule("pygit2.enums");
    if (enums == NULL) {
        return NULL;
    }

#define CACHE_PYGIT2_ENUM(name) do { \
    name##Enum = PyObject_GetAttrString(enums, #name); \
    if (name##Enum == NULL) { goto fail; } \
} while (0)

    CACHE_PYGIT2_ENUM(DeltaStatus);
    CACHE_PYGIT2_ENUM(DiffFlag);
    CACHE_PYGIT2_ENUM(FileMode);
    CACHE_PYGIT2_ENUM(FileStatus);
    CACHE_PYGIT2_ENUM(MergeAnalysis);
    CACHE_PYGIT2_ENUM(MergePreference);
    CACHE_PYGIT2_ENUM(ReferenceType);

#undef CACHE_PYGIT2_ENUM

    Py_RETURN_NONE;

fail:
    Py_DECREF(enums);
    forget_enums();
    return NULL;
}

void
free_module(void *self)
{
    forget_enums();
}


PyMethodDef module_methods[] = {
    {"discover_repository", discover_repository, METH_VARARGS, discover_repository__doc__},
    {"hash", hash, METH_VARARGS, hash__doc__},
    {"hashfile", hashfile, METH_VARARGS, hashfile__doc__},
    {"init_file_backend", init_file_backend, METH_VARARGS, init_file_backend__doc__},
    {"option", option, METH_VARARGS, option__doc__},
    {"reference_is_valid_name", reference_is_valid_name, METH_O, reference_is_valid_name__doc__},
    {"tree_entry_cmp", tree_entry_cmp, METH_VARARGS, tree_entry_cmp__doc__},
    {"filter_register", (PyCFunction)filter_register, METH_VARARGS | METH_KEYWORDS, filter_register__doc__},
    {"filter_unregister", filter_unregister, METH_VARARGS, filter_unregister__doc__},
    {"_cache_enums", _cache_enums, METH_NOARGS, _cache_enums__doc__},
    {NULL}
};

struct PyModuleDef moduledef = {
    PyModuleDef_HEAD_INIT,
    "_pygit2",                       /* m_name */
    "Python bindings for libgit2.",  /* m_doc */
    -1,                              /* m_size */
    module_methods,                  /* m_methods */
    NULL,                            /* m_reload */
    NULL,                            /* m_traverse */
    NULL,                            /* m_clear */
    free_module,                     /* m_free */
};

PyMODINIT_FUNC
PyInit__pygit2(void)
{
    PyObject *m = PyModule_Create(&moduledef);
    if (m == NULL)
        return NULL;

    /* libgit2 version info */
    ADD_CONSTANT_INT(m, LIBGIT2_VER_MAJOR)
    ADD_CONSTANT_INT(m, LIBGIT2_VER_MINOR)
    ADD_CONSTANT_INT(m, LIBGIT2_VER_REVISION)
    ADD_CONSTANT_STR(m, LIBGIT2_VERSION)

    /* libgit2 options */
    ADD_CONSTANT_INT(m, GIT_OPT_GET_MWINDOW_SIZE);
    ADD_CONSTANT_INT(m, GIT_OPT_SET_MWINDOW_SIZE);
    ADD_CONSTANT_INT(m, GIT_OPT_GET_MWINDOW_MAPPED_LIMIT);
    ADD_CONSTANT_INT(m, GIT_OPT_SET_MWINDOW_MAPPED_LIMIT);
    ADD_CONSTANT_INT(m, GIT_OPT_GET_SEARCH_PATH);
    ADD_CONSTANT_INT(m, GIT_OPT_SET_SEARCH_PATH);
    ADD_CONSTANT_INT(m, GIT_OPT_SET_CACHE_OBJECT_LIMIT);
    ADD_CONSTANT_INT(m, GIT_OPT_SET_CACHE_MAX_SIZE);
    ADD_CONSTANT_INT(m, GIT_OPT_ENABLE_CACHING);
    ADD_CONSTANT_INT(m, GIT_OPT_GET_CACHED_MEMORY);
    ADD_CONSTANT_INT(m, GIT_OPT_GET_TEMPLATE_PATH);
    ADD_CONSTANT_INT(m, GIT_OPT_SET_TEMPLATE_PATH);
    ADD_CONSTANT_INT(m, GIT_OPT_SET_SSL_CERT_LOCATIONS);
    ADD_CONSTANT_INT(m, GIT_OPT_SET_USER_AGENT);
    ADD_CONSTANT_INT(m, GIT_OPT_ENABLE_STRICT_OBJECT_CREATION);
    ADD_CONSTANT_INT(m, GIT_OPT_ENABLE_STRICT_SYMBOLIC_REF_CREATION);
    ADD_CONSTANT_INT(m, GIT_OPT_SET_SSL_CIPHERS);
    ADD_CONSTANT_INT(m, GIT_OPT_GET_USER_AGENT);
    ADD_CONSTANT_INT(m, GIT_OPT_ENABLE_OFS_DELTA);
    ADD_CONSTANT_INT(m, GIT_OPT_ENABLE_FSYNC_GITDIR);
    ADD_CONSTANT_INT(m, GIT_OPT_GET_WINDOWS_SHAREMODE);
    ADD_CONSTANT_INT(m, GIT_OPT_SET_WINDOWS_SHAREMODE);
    ADD_CONSTANT_INT(m, GIT_OPT_ENABLE_STRICT_HASH_VERIFICATION);
    ADD_CONSTANT_INT(m, GIT_OPT_SET_ALLOCATOR);
    ADD_CONSTANT_INT(m, GIT_OPT_ENABLE_UNSAVED_INDEX_SAFETY);
    ADD_CONSTANT_INT(m, GIT_OPT_GET_PACK_MAX_OBJECTS);
    ADD_CONSTANT_INT(m, GIT_OPT_SET_PACK_MAX_OBJECTS);
    ADD_CONSTANT_INT(m, GIT_OPT_DISABLE_PACK_KEEP_FILE_CHECKS);
    ADD_CONSTANT_INT(m, GIT_OPT_GET_OWNER_VALIDATION);
    ADD_CONSTANT_INT(m, GIT_OPT_SET_OWNER_VALIDATION);
    ADD_CONSTANT_INT(m, GIT_OPT_GET_MWINDOW_FILE_LIMIT);
    ADD_CONSTANT_INT(m, GIT_OPT_SET_MWINDOW_FILE_LIMIT);

    /* Exceptions */
    ADD_EXC(m, GitError, NULL);
    ADD_EXC(m, AlreadyExistsError, PyExc_ValueError);
    ADD_EXC(m, InvalidSpecError, PyExc_ValueError);

    /* Repository */
    INIT_TYPE(RepositoryType, NULL, PyType_GenericNew)
    ADD_TYPE(m, Repository)

    /* Odb */
    INIT_TYPE(OdbType, NULL, PyType_GenericNew)
    ADD_TYPE(m, Odb)

    INIT_TYPE(OdbBackendType, NULL, PyType_GenericNew)
    ADD_TYPE(m, OdbBackend)
    INIT_TYPE(OdbBackendPackType, &OdbBackendType, PyType_GenericNew)
    ADD_TYPE(m, OdbBackendPack)
    INIT_TYPE(OdbBackendLooseType, &OdbBackendType, PyType_GenericNew)
    ADD_TYPE(m, OdbBackendLoose)

    /* Oid */
    INIT_TYPE(OidType, NULL, PyType_GenericNew)
    ADD_TYPE(m, Oid)
    ADD_CONSTANT_INT(m, GIT_OID_RAWSZ)
    ADD_CONSTANT_INT(m, GIT_OID_HEXSZ)
    ADD_CONSTANT_STR(m, GIT_OID_HEX_ZERO)
    ADD_CONSTANT_INT(m, GIT_OID_MINPREFIXLEN)

    /*
     * Objects
     */
    INIT_TYPE(ObjectType, NULL, NULL)
    INIT_TYPE(CommitType, &ObjectType, NULL)
    INIT_TYPE(SignatureType, NULL, PyType_GenericNew)
    INIT_TYPE(TreeType, &ObjectType, NULL)
    INIT_TYPE(TreeIterType, NULL, NULL)
    INIT_TYPE(TreeBuilderType, NULL, NULL)
    INIT_TYPE(BlobType, &ObjectType, NULL)
    INIT_TYPE(TagType, &ObjectType, NULL)
    INIT_TYPE(RefsIteratorType, NULL, NULL)
    ADD_TYPE(m, Object)
    ADD_TYPE(m, Commit)
    ADD_TYPE(m, Signature)
    ADD_TYPE(m, Tree)
    ADD_TYPE(m, TreeBuilder)
    ADD_TYPE(m, Blob)
    ADD_TYPE(m, Tag)
    ADD_CONSTANT_INT(m, GIT_OBJECT_ANY)
    ADD_CONSTANT_INT(m, GIT_OBJECT_INVALID)
    ADD_CONSTANT_INT(m, GIT_OBJECT_COMMIT)
    ADD_CONSTANT_INT(m, GIT_OBJECT_TREE)
    ADD_CONSTANT_INT(m, GIT_OBJECT_BLOB)
    ADD_CONSTANT_INT(m, GIT_OBJECT_TAG)
    ADD_CONSTANT_INT(m, GIT_OBJECT_OFS_DELTA)
    ADD_CONSTANT_INT(m, GIT_OBJECT_REF_DELTA)
    /* Valid modes for index and tree entries. */
    ADD_CONSTANT_INT(m, GIT_FILEMODE_UNREADABLE)
    ADD_CONSTANT_INT(m, GIT_FILEMODE_TREE)
    ADD_CONSTANT_INT(m, GIT_FILEMODE_BLOB)
    ADD_CONSTANT_INT(m, GIT_FILEMODE_BLOB_EXECUTABLE)
    ADD_CONSTANT_INT(m, GIT_FILEMODE_LINK)
    ADD_CONSTANT_INT(m, GIT_FILEMODE_COMMIT)

    /*
     * Log
     */
    INIT_TYPE(WalkerType, NULL, NULL)
    ADD_TYPE(m, Walker);
    ADD_CONSTANT_INT(m, GIT_SORT_NONE)
    ADD_CONSTANT_INT(m, GIT_SORT_TOPOLOGICAL)
    ADD_CONSTANT_INT(m, GIT_SORT_TIME)
    ADD_CONSTANT_INT(m, GIT_SORT_REVERSE)

    /*
     * Reset
     */
    ADD_CONSTANT_INT(m, GIT_RESET_SOFT)
    ADD_CONSTANT_INT(m, GIT_RESET_MIXED)
    ADD_CONSTANT_INT(m, GIT_RESET_HARD)

    /* Refdb */
    INIT_TYPE(RefdbType, NULL, PyType_GenericNew)
    ADD_TYPE(m, Refdb)

    INIT_TYPE(RefdbBackendType, NULL, PyType_GenericNew)
    ADD_TYPE(m, RefdbBackend)
    INIT_TYPE(RefdbFsBackendType, &RefdbBackendType, PyType_GenericNew)
    ADD_TYPE(m, RefdbFsBackend)

    /*
     * References
     */
    INIT_TYPE(ReferenceType, NULL, PyType_GenericNew)
    INIT_TYPE(RefLogEntryType, NULL, NULL)
    INIT_TYPE(RefLogIterType, NULL, NULL)
    INIT_TYPE(NoteType, NULL, NULL)
    INIT_TYPE(NoteIterType, NULL, NULL)
    ADD_TYPE(m, Reference)
    ADD_TYPE(m, RefLogEntry)
    ADD_TYPE(m, Note)
    ADD_CONSTANT_INT(m, GIT_REFERENCES_ALL)
    ADD_CONSTANT_INT(m, GIT_REFERENCES_BRANCHES)
    ADD_CONSTANT_INT(m, GIT_REFERENCES_TAGS)

    /*
     * RevSpec
     */
    INIT_TYPE(RevSpecType, NULL, NULL)
    ADD_TYPE(m, RevSpec)
    ADD_CONSTANT_INT(m, GIT_REVSPEC_SINGLE)
    ADD_CONSTANT_INT(m, GIT_REVSPEC_RANGE)
    ADD_CONSTANT_INT(m, GIT_REVSPEC_MERGE_BASE)

    /*
     * Worktree
     */
    INIT_TYPE(WorktreeType, NULL, NULL)
    ADD_TYPE(m, Worktree)

    /*
     * Branches
     */
    INIT_TYPE(BranchType, &ReferenceType, NULL);
    ADD_TYPE(m, Branch)
    ADD_CONSTANT_INT(m, GIT_BRANCH_LOCAL)
    ADD_CONSTANT_INT(m, GIT_BRANCH_REMOTE)
    ADD_CONSTANT_INT(m, GIT_BRANCH_ALL)

    /*
     * Index & Working copy
     */
    /* Status */
    ADD_CONSTANT_INT(m, GIT_STATUS_CURRENT)
    ADD_CONSTANT_INT(m, GIT_STATUS_INDEX_NEW)
    ADD_CONSTANT_INT(m, GIT_STATUS_INDEX_MODIFIED)
    ADD_CONSTANT_INT(m, GIT_STATUS_INDEX_DELETED)
    ADD_CONSTANT_INT(m, GIT_STATUS_INDEX_RENAMED)
    ADD_CONSTANT_INT(m, GIT_STATUS_INDEX_TYPECHANGE)
    ADD_CONSTANT_INT(m, GIT_STATUS_WT_NEW)
    ADD_CONSTANT_INT(m, GIT_STATUS_WT_MODIFIED)
    ADD_CONSTANT_INT(m, GIT_STATUS_WT_DELETED)
    ADD_CONSTANT_INT(m, GIT_STATUS_WT_TYPECHANGE)
    ADD_CONSTANT_INT(m, GIT_STATUS_WT_RENAMED)
    ADD_CONSTANT_INT(m, GIT_STATUS_WT_UNREADABLE)
    ADD_CONSTANT_INT(m, GIT_STATUS_IGNORED) /* Flags for ignored files */
    ADD_CONSTANT_INT(m, GIT_STATUS_CONFLICTED)
    /* Different checkout strategies */
    ADD_CONSTANT_INT(m, GIT_CHECKOUT_NONE)
    ADD_CONSTANT_INT(m, GIT_CHECKOUT_SAFE)
    ADD_CONSTANT_INT(m, GIT_CHECKOUT_FORCE)
    ADD_CONSTANT_INT(m, GIT_CHECKOUT_RECREATE_MISSING)
    ADD_CONSTANT_INT(m, GIT_CHECKOUT_ALLOW_CONFLICTS)
    ADD_CONSTANT_INT(m, GIT_CHECKOUT_REMOVE_UNTRACKED)
    ADD_CONSTANT_INT(m, GIT_CHECKOUT_REMOVE_IGNORED)
    ADD_CONSTANT_INT(m, GIT_CHECKOUT_UPDATE_ONLY)
    ADD_CONSTANT_INT(m, GIT_CHECKOUT_DONT_UPDATE_INDEX)
    ADD_CONSTANT_INT(m, GIT_CHECKOUT_NO_REFRESH)
    ADD_CONSTANT_INT(m, GIT_CHECKOUT_SKIP_UNMERGED)
    ADD_CONSTANT_INT(m, GIT_CHECKOUT_USE_OURS)
    ADD_CONSTANT_INT(m, GIT_CHECKOUT_USE_THEIRS)
    ADD_CONSTANT_INT(m, GIT_CHECKOUT_DISABLE_PATHSPEC_MATCH)
    ADD_CONSTANT_INT(m, GIT_CHECKOUT_SKIP_LOCKED_DIRECTORIES)
    ADD_CONSTANT_INT(m, GIT_CHECKOUT_DONT_OVERWRITE_IGNORED)
    ADD_CONSTANT_INT(m, GIT_CHECKOUT_CONFLICT_STYLE_MERGE)
    ADD_CONSTANT_INT(m, GIT_CHECKOUT_CONFLICT_STYLE_DIFF3)
    ADD_CONSTANT_INT(m, GIT_CHECKOUT_DONT_REMOVE_EXISTING)
    ADD_CONSTANT_INT(m, GIT_CHECKOUT_DONT_WRITE_INDEX)
    ADD_CONSTANT_INT(m, GIT_CHECKOUT_DRY_RUN)
    ADD_CONSTANT_INT(m, GIT_CHECKOUT_CONFLICT_STYLE_ZDIFF3)

    /*
     * Diff
     */
    INIT_TYPE(DiffType, NULL, NULL)
    INIT_TYPE(DeltasIterType, NULL, NULL)
    INIT_TYPE(DiffIterType, NULL, NULL)
    INIT_TYPE(DiffDeltaType, NULL, NULL)
    INIT_TYPE(DiffFileType, NULL, NULL)
    INIT_TYPE(DiffHunkType, NULL, NULL)
    INIT_TYPE(DiffLineType, NULL, NULL)
    INIT_TYPE(DiffStatsType, NULL, NULL)
    INIT_TYPE(PatchType, NULL, NULL)
    ADD_TYPE(m, Diff)
    ADD_TYPE(m, DiffDelta)
    ADD_TYPE(m, DiffFile)
    ADD_TYPE(m, DiffHunk)
    ADD_TYPE(m, DiffLine)
    ADD_TYPE(m, DiffStats)
    ADD_TYPE(m, Patch)

    /* (git_diff_options in libgit2) */
    ADD_CONSTANT_INT(m, GIT_DIFF_NORMAL)
    ADD_CONSTANT_INT(m, GIT_DIFF_REVERSE)
    ADD_CONSTANT_INT(m, GIT_DIFF_INCLUDE_IGNORED)
    ADD_CONSTANT_INT(m, GIT_DIFF_RECURSE_IGNORED_DIRS)
    ADD_CONSTANT_INT(m, GIT_DIFF_INCLUDE_UNTRACKED)
    ADD_CONSTANT_INT(m, GIT_DIFF_RECURSE_UNTRACKED_DIRS)
    ADD_CONSTANT_INT(m, GIT_DIFF_INCLUDE_UNMODIFIED)
    ADD_CONSTANT_INT(m, GIT_DIFF_INCLUDE_TYPECHANGE)
    ADD_CONSTANT_INT(m, GIT_DIFF_INCLUDE_TYPECHANGE_TREES)
    ADD_CONSTANT_INT(m, GIT_DIFF_IGNORE_FILEMODE)
    ADD_CONSTANT_INT(m, GIT_DIFF_IGNORE_SUBMODULES)
    ADD_CONSTANT_INT(m, GIT_DIFF_IGNORE_CASE)
    ADD_CONSTANT_INT(m, GIT_DIFF_INCLUDE_CASECHANGE)
    ADD_CONSTANT_INT(m, GIT_DIFF_DISABLE_PATHSPEC_MATCH)
    ADD_CONSTANT_INT(m, GIT_DIFF_SKIP_BINARY_CHECK)
    ADD_CONSTANT_INT(m, GIT_DIFF_ENABLE_FAST_UNTRACKED_DIRS)
    ADD_CONSTANT_INT(m, GIT_DIFF_UPDATE_INDEX)
    ADD_CONSTANT_INT(m, GIT_DIFF_INCLUDE_UNREADABLE)
    ADD_CONSTANT_INT(m, GIT_DIFF_INCLUDE_UNREADABLE_AS_UNTRACKED)
    ADD_CONSTANT_INT(m, GIT_DIFF_INDENT_HEURISTIC)
    ADD_CONSTANT_INT(m, GIT_DIFF_IGNORE_BLANK_LINES)
    ADD_CONSTANT_INT(m, GIT_DIFF_FORCE_TEXT)
    ADD_CONSTANT_INT(m, GIT_DIFF_FORCE_BINARY)
    ADD_CONSTANT_INT(m, GIT_DIFF_IGNORE_WHITESPACE)
    ADD_CONSTANT_INT(m, GIT_DIFF_IGNORE_WHITESPACE_CHANGE)
    ADD_CONSTANT_INT(m, GIT_DIFF_IGNORE_WHITESPACE_EOL)
    ADD_CONSTANT_INT(m, GIT_DIFF_SHOW_UNTRACKED_CONTENT)
    ADD_CONSTANT_INT(m, GIT_DIFF_SHOW_UNMODIFIED)
    ADD_CONSTANT_INT(m, GIT_DIFF_PATIENCE)
    ADD_CONSTANT_INT(m, GIT_DIFF_MINIMAL)
    ADD_CONSTANT_INT(m, GIT_DIFF_SHOW_BINARY)

    /* Formatting options for diff stats (git_diff_stats_format_t in libgit2) */
    ADD_CONSTANT_INT(m, GIT_DIFF_STATS_NONE)
    ADD_CONSTANT_INT(m, GIT_DIFF_STATS_FULL)
    ADD_CONSTANT_INT(m, GIT_DIFF_STATS_SHORT)
    ADD_CONSTANT_INT(m, GIT_DIFF_STATS_NUMBER)
    ADD_CONSTANT_INT(m, GIT_DIFF_STATS_INCLUDE_SUMMARY)

    /* Flags for Diff.find_similar (git_diff_find_t in libgit2) */
    ADD_CONSTANT_INT(m, GIT_DIFF_FIND_BY_CONFIG) /** Obey diff.renames */
    ADD_CONSTANT_INT(m, GIT_DIFF_FIND_RENAMES) /* --find-renames */
    ADD_CONSTANT_INT(m, GIT_DIFF_FIND_RENAMES_FROM_REWRITES) /* --break-rewrites=N */
    ADD_CONSTANT_INT(m, GIT_DIFF_FIND_COPIES) /* --find-copies */
    ADD_CONSTANT_INT(m, GIT_DIFF_FIND_COPIES_FROM_UNMODIFIED) /* --find-copies-harder */
    ADD_CONSTANT_INT(m, GIT_DIFF_FIND_REWRITES) /* --break-rewrites=/M */
    ADD_CONSTANT_INT(m, GIT_DIFF_BREAK_REWRITES)
    ADD_CONSTANT_INT(m, GIT_DIFF_FIND_AND_BREAK_REWRITES)
    ADD_CONSTANT_INT(m, GIT_DIFF_FIND_FOR_UNTRACKED)
    ADD_CONSTANT_INT(m, GIT_DIFF_FIND_ALL) /* Turn on all finding features. */
    ADD_CONSTANT_INT(m, GIT_DIFF_FIND_IGNORE_LEADING_WHITESPACE)
    ADD_CONSTANT_INT(m, GIT_DIFF_FIND_IGNORE_WHITESPACE)
    ADD_CONSTANT_INT(m, GIT_DIFF_FIND_DONT_IGNORE_WHITESPACE)
    ADD_CONSTANT_INT(m, GIT_DIFF_FIND_EXACT_MATCH_ONLY)
    ADD_CONSTANT_INT(m, GIT_DIFF_BREAK_REWRITES_FOR_RENAMES_ONLY)
    ADD_CONSTANT_INT(m, GIT_DIFF_FIND_REMOVE_UNMODIFIED)

    /* DiffDelta and DiffFile flags (git_diff_flag_t in libgit2) */
    ADD_CONSTANT_INT(m, GIT_DIFF_FLAG_BINARY)
    ADD_CONSTANT_INT(m, GIT_DIFF_FLAG_NOT_BINARY)
    ADD_CONSTANT_INT(m, GIT_DIFF_FLAG_VALID_ID)
    ADD_CONSTANT_INT(m, GIT_DIFF_FLAG_EXISTS)
    ADD_CONSTANT_INT(m, GIT_DIFF_FLAG_VALID_SIZE)

    /* DiffDelta.status (git_delta_t in libgit2) */
    ADD_CONSTANT_INT(m, GIT_DELTA_UNMODIFIED)
    ADD_CONSTANT_INT(m, GIT_DELTA_ADDED)
    ADD_CONSTANT_INT(m, GIT_DELTA_DELETED)
    ADD_CONSTANT_INT(m, GIT_DELTA_MODIFIED)
    ADD_CONSTANT_INT(m, GIT_DELTA_RENAMED)
    ADD_CONSTANT_INT(m, GIT_DELTA_COPIED)
    ADD_CONSTANT_INT(m, GIT_DELTA_IGNORED)
    ADD_CONSTANT_INT(m, GIT_DELTA_UNTRACKED)
    ADD_CONSTANT_INT(m, GIT_DELTA_TYPECHANGE)
    ADD_CONSTANT_INT(m, GIT_DELTA_UNREADABLE)
    ADD_CONSTANT_INT(m, GIT_DELTA_CONFLICTED)

    /* Config */
    ADD_CONSTANT_INT(m, GIT_CONFIG_LEVEL_PROGRAMDATA);
    ADD_CONSTANT_INT(m, GIT_CONFIG_LEVEL_SYSTEM);
    ADD_CONSTANT_INT(m, GIT_CONFIG_LEVEL_XDG);
    ADD_CONSTANT_INT(m, GIT_CONFIG_LEVEL_GLOBAL);
    ADD_CONSTANT_INT(m, GIT_CONFIG_LEVEL_LOCAL);
    ADD_CONSTANT_INT(m, GIT_CONFIG_LEVEL_WORKTREE);
    ADD_CONSTANT_INT(m, GIT_CONFIG_LEVEL_APP);
    ADD_CONSTANT_INT(m, GIT_CONFIG_HIGHEST_LEVEL);

    /* Blame */
    ADD_CONSTANT_INT(m, GIT_BLAME_NORMAL)
    ADD_CONSTANT_INT(m, GIT_BLAME_TRACK_COPIES_SAME_FILE)
    ADD_CONSTANT_INT(m, GIT_BLAME_TRACK_COPIES_SAME_COMMIT_MOVES)
    ADD_CONSTANT_INT(m, GIT_BLAME_TRACK_COPIES_SAME_COMMIT_COPIES)
    ADD_CONSTANT_INT(m, GIT_BLAME_TRACK_COPIES_ANY_COMMIT_COPIES)
    ADD_CONSTANT_INT(m, GIT_BLAME_FIRST_PARENT)
    ADD_CONSTANT_INT(m, GIT_BLAME_USE_MAILMAP)
    ADD_CONSTANT_INT(m, GIT_BLAME_IGNORE_WHITESPACE)

    /* Merge */
    ADD_CONSTANT_INT(m, GIT_MERGE_ANALYSIS_NONE)
    ADD_CONSTANT_INT(m, GIT_MERGE_ANALYSIS_NORMAL)
    ADD_CONSTANT_INT(m, GIT_MERGE_ANALYSIS_UP_TO_DATE)
    ADD_CONSTANT_INT(m, GIT_MERGE_ANALYSIS_FASTFORWARD)
    ADD_CONSTANT_INT(m, GIT_MERGE_ANALYSIS_UNBORN)
    ADD_CONSTANT_INT(m, GIT_MERGE_PREFERENCE_NONE)
    ADD_CONSTANT_INT(m, GIT_MERGE_PREFERENCE_NO_FASTFORWARD)
    ADD_CONSTANT_INT(m, GIT_MERGE_PREFERENCE_FASTFORWARD_ONLY)

    /* Describe */
    ADD_CONSTANT_INT(m, GIT_DESCRIBE_DEFAULT);
    ADD_CONSTANT_INT(m, GIT_DESCRIBE_TAGS);
    ADD_CONSTANT_INT(m, GIT_DESCRIBE_ALL);

    /* Stash */
    ADD_CONSTANT_INT(m, GIT_STASH_DEFAULT);
    ADD_CONSTANT_INT(m, GIT_STASH_KEEP_INDEX);
    ADD_CONSTANT_INT(m, GIT_STASH_INCLUDE_UNTRACKED);
    ADD_CONSTANT_INT(m, GIT_STASH_INCLUDE_IGNORED);
    ADD_CONSTANT_INT(m, GIT_STASH_KEEP_ALL);
    ADD_CONSTANT_INT(m, GIT_STASH_APPLY_DEFAULT);
    ADD_CONSTANT_INT(m, GIT_STASH_APPLY_REINSTATE_INDEX);

    /* Apply location */
    ADD_CONSTANT_INT(m, GIT_APPLY_LOCATION_WORKDIR);
    ADD_CONSTANT_INT(m, GIT_APPLY_LOCATION_INDEX);
    ADD_CONSTANT_INT(m, GIT_APPLY_LOCATION_BOTH);

    /* Submodule */
    ADD_CONSTANT_INT(m, GIT_SUBMODULE_IGNORE_UNSPECIFIED);
    ADD_CONSTANT_INT(m, GIT_SUBMODULE_IGNORE_NONE);
    ADD_CONSTANT_INT(m, GIT_SUBMODULE_IGNORE_UNTRACKED);
    ADD_CONSTANT_INT(m, GIT_SUBMODULE_IGNORE_DIRTY);
    ADD_CONSTANT_INT(m, GIT_SUBMODULE_IGNORE_ALL);

    ADD_CONSTANT_INT(m, GIT_SUBMODULE_STATUS_IN_HEAD);
    ADD_CONSTANT_INT(m, GIT_SUBMODULE_STATUS_IN_INDEX);
    ADD_CONSTANT_INT(m, GIT_SUBMODULE_STATUS_IN_CONFIG);
    ADD_CONSTANT_INT(m, GIT_SUBMODULE_STATUS_IN_WD);
    ADD_CONSTANT_INT(m, GIT_SUBMODULE_STATUS_INDEX_ADDED);
    ADD_CONSTANT_INT(m, GIT_SUBMODULE_STATUS_INDEX_DELETED);
    ADD_CONSTANT_INT(m, GIT_SUBMODULE_STATUS_INDEX_MODIFIED);
    ADD_CONSTANT_INT(m, GIT_SUBMODULE_STATUS_WD_UNINITIALIZED);
    ADD_CONSTANT_INT(m, GIT_SUBMODULE_STATUS_WD_ADDED);
    ADD_CONSTANT_INT(m, GIT_SUBMODULE_STATUS_WD_DELETED);
    ADD_CONSTANT_INT(m, GIT_SUBMODULE_STATUS_WD_MODIFIED);
    ADD_CONSTANT_INT(m, GIT_SUBMODULE_STATUS_WD_INDEX_MODIFIED);
    ADD_CONSTANT_INT(m, GIT_SUBMODULE_STATUS_WD_WD_MODIFIED);
    ADD_CONSTANT_INT(m, GIT_SUBMODULE_STATUS_WD_UNTRACKED);

    /* Mailmap */
    INIT_TYPE(MailmapType, NULL, PyType_GenericNew)
    ADD_TYPE(m, Mailmap)

    /* Stash */
    INIT_TYPE(StashType, NULL, NULL)
    ADD_TYPE(m, Stash)

    /* Blob filter */
    ADD_CONSTANT_INT(m, GIT_BLOB_FILTER_CHECK_FOR_BINARY);
    ADD_CONSTANT_INT(m, GIT_BLOB_FILTER_NO_SYSTEM_ATTRIBUTES);
    ADD_CONSTANT_INT(m, GIT_BLOB_FILTER_ATTRIBUTES_FROM_HEAD);
    ADD_CONSTANT_INT(m, GIT_BLOB_FILTER_ATTRIBUTES_FROM_COMMIT);
    ADD_CONSTANT_INT(m, GIT_FILTER_DRIVER_PRIORITY);
    ADD_CONSTANT_INT(m, GIT_FILTER_TO_WORKTREE);
    ADD_CONSTANT_INT(m, GIT_FILTER_SMUDGE);
    ADD_CONSTANT_INT(m, GIT_FILTER_TO_ODB);
    ADD_CONSTANT_INT(m, GIT_FILTER_CLEAN);
    ADD_CONSTANT_INT(m, GIT_FILTER_DEFAULT);
    ADD_CONSTANT_INT(m, GIT_FILTER_ALLOW_UNSAFE);
    ADD_CONSTANT_INT(m, GIT_FILTER_NO_SYSTEM_ATTRIBUTES);
    ADD_CONSTANT_INT(m, GIT_FILTER_ATTRIBUTES_FROM_HEAD);
    ADD_CONSTANT_INT(m, GIT_FILTER_ATTRIBUTES_FROM_COMMIT);

    INIT_TYPE(FilterSourceType, NULL, NULL);
    ADD_TYPE(m, FilterSource);

    /* Global initialization of libgit2 */
    git_libgit2_init();

    return m;

fail:
    Py_DECREF(m);
    return NULL;
}
