#include "cache.h"
#include "submodule.h"
#include "dir.h"
#include "diff.h"
#include "commit.h"
#include "revision.h"
#include "run-command.h"
#include "diffcore.h"

static int add_submodule_odb(const char *path)
{
	struct strbuf objects_directory = STRBUF_INIT;
	struct alternate_object_database *alt_odb;
	int ret = 0;
	const char *git_dir;

	strbuf_addf(&objects_directory, "%s/.git", path);
	git_dir = read_gitfile_gently(objects_directory.buf);
	if (git_dir) {
		strbuf_reset(&objects_directory);
		strbuf_addstr(&objects_directory, git_dir);
	}
	strbuf_addstr(&objects_directory, "/objects/");
	if (!is_directory(objects_directory.buf)) {
		ret = -1;
		goto done;
	}
	/* avoid adding it twice */
	for (alt_odb = alt_odb_list; alt_odb; alt_odb = alt_odb->next)
		if (alt_odb->name - alt_odb->base == objects_directory.len &&
				!strncmp(alt_odb->base, objects_directory.buf,
					objects_directory.len))
			goto done;

	alt_odb = xmalloc(objects_directory.len + 42 + sizeof(*alt_odb));
	alt_odb->next = alt_odb_list;
	strcpy(alt_odb->base, objects_directory.buf);
	alt_odb->name = alt_odb->base + objects_directory.len;
	alt_odb->name[2] = '/';
	alt_odb->name[40] = '\0';
	alt_odb->name[41] = '\0';
	alt_odb_list = alt_odb;
	prepare_alt_odb();
done:
	strbuf_release(&objects_directory);
	return ret;
}

void handle_ignore_submodules_arg(struct diff_options *diffopt,
				  const char *arg)
{
	if (!strcmp(arg, "all"))
		DIFF_OPT_SET(diffopt, IGNORE_SUBMODULES);
	else if (!strcmp(arg, "untracked"))
		DIFF_OPT_SET(diffopt, IGNORE_UNTRACKED_IN_SUBMODULES);
	else if (!strcmp(arg, "dirty"))
		DIFF_OPT_SET(diffopt, IGNORE_DIRTY_SUBMODULES);
	else
		die("bad --ignore-submodules argument: %s", arg);
}

void show_submodule_summary(FILE *f, const char *path,
		unsigned char one[20], unsigned char two[20],
		unsigned dirty_submodule,
		const char *del, const char *add, const char *reset)
{
	struct rev_info rev;
	struct commit *commit, *left = left, *right = right;
	struct commit_list *merge_bases, *list;
	const char *message = NULL;
	struct strbuf sb = STRBUF_INIT;
	static const char *format = "  %m %s";
	int fast_forward = 0, fast_backward = 0;

	if (is_null_sha1(two))
		message = "(submodule deleted)";
	else if (add_submodule_odb(path))
		message = "(not checked out)";
	else if (is_null_sha1(one))
		message = "(new submodule)";
	else if (!(left = lookup_commit_reference(one)) ||
		 !(right = lookup_commit_reference(two)))
		message = "(commits not present)";

	if (!message) {
		init_revisions(&rev, NULL);
		setup_revisions(0, NULL, &rev, NULL);
		rev.left_right = 1;
		rev.first_parent_only = 1;
		left->object.flags |= SYMMETRIC_LEFT;
		add_pending_object(&rev, &left->object, path);
		add_pending_object(&rev, &right->object, path);
		merge_bases = get_merge_bases(left, right, 1);
		if (merge_bases) {
			if (merge_bases->item == left)
				fast_forward = 1;
			else if (merge_bases->item == right)
				fast_backward = 1;
		}
		for (list = merge_bases; list; list = list->next) {
			list->item->object.flags |= UNINTERESTING;
			add_pending_object(&rev, &list->item->object,
				sha1_to_hex(list->item->object.sha1));
		}
		if (prepare_revision_walk(&rev))
			message = "(revision walker failed)";
	}

	if (dirty_submodule & DIRTY_SUBMODULE_UNTRACKED)
		fprintf(f, "Submodule %s contains untracked content\n", path);
	if (dirty_submodule & DIRTY_SUBMODULE_MODIFIED)
		fprintf(f, "Submodule %s contains modified content\n", path);

	if (!hashcmp(one, two)) {
		strbuf_release(&sb);
		return;
	}

	strbuf_addf(&sb, "Submodule %s %s..", path,
			find_unique_abbrev(one, DEFAULT_ABBREV));
	if (!fast_backward && !fast_forward)
		strbuf_addch(&sb, '.');
	strbuf_addf(&sb, "%s", find_unique_abbrev(two, DEFAULT_ABBREV));
	if (message)
		strbuf_addf(&sb, " %s\n", message);
	else
		strbuf_addf(&sb, "%s:\n", fast_backward ? " (rewind)" : "");
	fwrite(sb.buf, sb.len, 1, f);

	if (!message) {
		while ((commit = get_revision(&rev))) {
			struct pretty_print_context ctx = {0};
			ctx.date_mode = rev.date_mode;
			strbuf_setlen(&sb, 0);
			if (commit->object.flags & SYMMETRIC_LEFT) {
				if (del)
					strbuf_addstr(&sb, del);
			}
			else if (add)
				strbuf_addstr(&sb, add);
			format_commit_message(commit, format, &sb, &ctx);
			if (reset)
				strbuf_addstr(&sb, reset);
			strbuf_addch(&sb, '\n');
			fprintf(f, "%s", sb.buf);
		}
		clear_commit_marks(left, ~0);
		clear_commit_marks(right, ~0);
	}
	strbuf_release(&sb);
}

unsigned is_submodule_modified(const char *path, int ignore_untracked)
{
	ssize_t len;
	struct child_process cp;
	const char *argv[] = {
		"status",
		"--porcelain",
		NULL,
		NULL,
	};
	struct strbuf buf = STRBUF_INIT;
	unsigned dirty_submodule = 0;
	const char *line, *next_line;
	const char *git_dir;

	strbuf_addf(&buf, "%s/.git", path);
	git_dir = read_gitfile_gently(buf.buf);
	if (!git_dir)
		git_dir = buf.buf;
	if (!is_directory(git_dir)) {
		strbuf_release(&buf);
		/* The submodule is not checked out, so it is not modified */
		return 0;

	}
	strbuf_reset(&buf);

	if (ignore_untracked)
		argv[2] = "-uno";

	memset(&cp, 0, sizeof(cp));
	cp.argv = argv;
	cp.env = local_repo_env;
	cp.git_cmd = 1;
	cp.no_stdin = 1;
	cp.out = -1;
	cp.dir = path;
	if (start_command(&cp))
		die("Could not run git status --porcelain");

	len = strbuf_read(&buf, cp.out, 1024);
	line = buf.buf;
	while (len > 2) {
		if ((line[0] == '?') && (line[1] == '?')) {
			dirty_submodule |= DIRTY_SUBMODULE_UNTRACKED;
			if (dirty_submodule & DIRTY_SUBMODULE_MODIFIED)
				break;
		} else {
			dirty_submodule |= DIRTY_SUBMODULE_MODIFIED;
			if (ignore_untracked ||
			    (dirty_submodule & DIRTY_SUBMODULE_UNTRACKED))
				break;
		}
		next_line = strchr(line, '\n');
		if (!next_line)
			break;
		next_line++;
		len -= (next_line - line);
		line = next_line;
	}
	close(cp.out);

	if (finish_command(&cp))
		die("git status --porcelain failed");

	strbuf_release(&buf);
	return dirty_submodule;
}