#include "cache.h"

#include "cache-tree.h"

#include "tree.h"

#include "object-store.h"

#include "blob.h"

#include "commit.h"

#include "tag.h"

#include "alloc.h"

#include "tree-walk.h"

#include "repository.h"

const char *tree_type = "tree";

static int read_one_entry_opt(struct index_state *istate,

			      const struct object_id *oid,

			      const char *base, int baselen,

			      const char *pathname,

			      unsigned mode, int stage, int opt)

{

	int len;

	struct cache_entry *ce;

	if (S_ISDIR(mode))

		return READ_TREE_RECURSIVE;

	len = strlen(pathname);

	ce = make_empty_cache_entry(istate, baselen + len);

	ce->ce_mode = create_ce_mode(mode);

	ce->ce_flags = create_ce_flags(stage);

	ce->ce_namelen = baselen + len;

	memcpy(ce->name, base, baselen);

	memcpy(ce->name + baselen, pathname, len+1);

	oidcpy(&ce->oid, oid);

	return add_index_entry(istate, ce, opt);

}

static int read_one_entry(const struct object_id *oid, struct strbuf *base,

			  const char *pathname, unsigned mode, int stage,

			  void *context)

{

	struct index_state *istate = context;

	return read_one_entry_opt(istate, oid, base->buf, base->len, pathname,

				  mode, stage,

				  ADD_CACHE_OK_TO_ADD|ADD_CACHE_SKIP_DFCHECK);

}

/*

 * This is used when the caller knows there is no existing entries at

 * the stage that will conflict with the entry being added.

 */

static int read_one_entry_quick(const struct object_id *oid, struct strbuf *base,

				const char *pathname, unsigned mode, int stage,

				void *context)

{

	struct index_state *istate = context;

	return read_one_entry_opt(istate, oid, base->buf, base->len, pathname,

				  mode, stage,

				  ADD_CACHE_JUST_APPEND);

}

static int read_tree_1(struct repository *r,

		       struct tree *tree, struct strbuf *base,

		       int stage, const struct pathspec *pathspec,

		       read_tree_fn_t fn, void *context)

{

	struct tree_desc desc;

	struct name_entry entry;

	struct object_id oid;

	int len, oldlen = base->len;

	enum interesting retval = entry_not_interesting;

	if (parse_tree(tree))

		return -1;

	init_tree_desc(&desc, tree->buffer, tree->size);

	while (tree_entry(&desc, &entry)) {

		if (retval != all_entries_interesting) {

			retval = tree_entry_interesting(r->index, &entry,

							base, 0, pathspec);

			if (retval == all_entries_not_interesting)

				break;

			if (retval == entry_not_interesting)

				continue;

		}

		switch (fn(&entry.oid, base,

			   entry.path, entry.mode, stage, context)) {

		case 0:

			continue;

		case READ_TREE_RECURSIVE:

			break;

		default:

			return -1;

		}

		if (S_ISDIR(entry.mode))

			oidcpy(&oid, &entry.oid);

		else if (S_ISGITLINK(entry.mode)) {

			struct commit *commit;

			commit = lookup_commit(r, &entry.oid);

			if (!commit)

				die("Commit %s in submodule path %s%s not found",

				    oid_to_hex(&entry.oid),

				    base->buf, entry.path);

			if (parse_commit(commit))

				die("Invalid commit %s in submodule path %s%s",

				    oid_to_hex(&entry.oid),

				    base->buf, entry.path);

			oidcpy(&oid, get_commit_tree_oid(commit));

		}

		else

			continue;

		len = tree_entry_len(&entry);

		strbuf_add(base, entry.path, len);

		strbuf_addch(base, '/');

		retval = read_tree_1(r, lookup_tree(r, &oid),

				     base, stage, pathspec,

				     fn, context);

		strbuf_setlen(base, oldlen);

		if (retval)

			return -1;

	}

	return 0;

}

int read_tree_recursive(struct repository *r,

			struct tree *tree,

			const char *base, int baselen,

			int stage, const struct pathspec *pathspec,

			read_tree_fn_t fn, void *context)

{

	struct strbuf sb = STRBUF_INIT;

	int ret;

	strbuf_add(&sb, base, baselen);

	ret = read_tree_1(r, tree, &sb, stage, pathspec, fn, context);

	strbuf_release(&sb);

	return ret;

}

static int cmp_cache_name_compare(const void *a_, const void *b_)

{

	const struct cache_entry *ce1, *ce2;

	ce1 = *((const struct cache_entry **)a_);

	ce2 = *((const struct cache_entry **)b_);

	return cache_name_stage_compare(ce1->name, ce1->ce_namelen, ce_stage(ce1),

				  ce2->name, ce2->ce_namelen, ce_stage(ce2));

}

int read_tree(struct repository *r, struct tree *tree, int stage,

	      struct pathspec *match, struct index_state *istate)

{

	read_tree_fn_t fn = NULL;

	int i, err;

	/*

	 * Currently the only existing callers of this function all

	 * call it with stage=1 and after making sure there is nothing

	 * at that stage; we could always use read_one_entry_quick().

	 *

	 * But when we decide to straighten out git-read-tree not to

	 * use unpack_trees() in some cases, this will probably start

	 * to matter.

	 */

	/*

	 * See if we have cache entry at the stage.  If so,

	 * do it the original slow way, otherwise, append and then

	 * sort at the end.

	 */

	for (i = 0; !fn && i < istate->cache_nr; i++) {

		const struct cache_entry *ce = istate->cache[i];

		if (ce_stage(ce) == stage)

			fn = read_one_entry;

	}

	if (!fn)

		fn = read_one_entry_quick;

	err = read_tree_recursive(r, tree, "", 0, stage, match, fn, istate);

	if (fn == read_one_entry || err)

		return err;

	/*

	 * Sort the cache entry -- we need to nuke the cache tree, though.

	 */

	cache_tree_free(&istate->cache_tree);

	QSORT(istate->cache, istate->cache_nr, cmp_cache_name_compare);

	return 0;

}

struct tree *lookup_tree(struct repository *r, const struct object_id *oid)

{

	struct object *obj = lookup_object(r, oid);

	if (!obj)

		return create_object(r, oid, alloc_tree_node(r));

	return object_as_type(r, obj, OBJ_TREE, 0);

}

int parse_tree_buffer(struct tree *item, void *buffer, unsigned long size)

{

	if (item->object.parsed)

		return 0;

	item->object.parsed = 1;

	item->buffer = buffer;

	item->size = size;

	return 0;

}

int parse_tree_gently(struct tree *item, int quiet_on_missing)

{

	 enum object_type type;

	 void *buffer;

	 unsigned long size;

	if (item->object.parsed)

		return 0;

	buffer = read_object_file(&item->object.oid, &type, &size);

	if (!buffer)

		return quiet_on_missing ? -1 :

			error("Could not read %s",

			     oid_to_hex(&item->object.oid));

	if (type != OBJ_TREE) {

		free(buffer);

		return error("Object %s not a tree",

			     oid_to_hex(&item->object.oid));

	}

	return parse_tree_buffer(item, buffer, size);

}

void free_tree_buffer(struct tree *tree)

{

	FREE_AND_NULL(tree->buffer);

	tree->size = 0;

	tree->object.parsed = 0;

}

struct tree *parse_tree_indirect(const struct object_id *oid)

{

	struct repository *r = the_repository;

	struct object *obj = parse_object(r, oid);

	return (struct tree *)repo_peel_to_type(r, NULL, 0, obj, OBJ_TREE);

}