/*
 * Copyright (C) the Rugged contributors.  All rights reserved.
 *
 * This file is part of Rugged, distributed under the MIT license.
 * For full terms see the included LICENSE file.
 */

#include "rugged.h"

extern VALUE rb_cRuggedDiff;
VALUE rb_cRuggedDiffHunk;


VALUE rugged_diff_hunk_new(VALUE owner, size_t hunk_idx, const git_diff_hunk *hunk, size_t lines_in_hunk)
{
	VALUE rb_hunk = rb_class_new_instance(0, NULL, rb_cRuggedDiffHunk);
	rugged_set_owner(rb_hunk, owner);

	rb_iv_set(rb_hunk, "@header", rb_str_new(hunk->header, hunk->header_len));
	rb_iv_set(rb_hunk, "@line_count", INT2FIX(lines_in_hunk));
	rb_iv_set(rb_hunk, "@hunk_index", INT2FIX(hunk_idx));

	rb_iv_set(rb_hunk, "@old_start", INT2FIX(hunk->old_start));
	rb_iv_set(rb_hunk, "@old_lines", INT2FIX(hunk->old_lines));
	rb_iv_set(rb_hunk, "@new_start", INT2FIX(hunk->new_start));
	rb_iv_set(rb_hunk, "@new_lines", INT2FIX(hunk->new_lines));

	return rb_hunk;
}

/*
 *  call-seq:
 *    hunk.each_line { |line| } -> self
 *    hunk.each_line -> Enumerator
 *
 *  If given a block, yields each line that is part of the current hunk.
 *
 *  If no block is given, an enumerator is returned instead.
 */
static VALUE rb_git_diff_hunk_each_line(VALUE self)
{
	git_patch *patch;
	int error = 0, l, lines_count, hunk_idx;

	RETURN_ENUMERATOR(self, 0, 0);

	Data_Get_Struct(rugged_owner(self), git_patch, patch);

	lines_count = FIX2INT(rb_iv_get(self, "@line_count"));
	hunk_idx = FIX2INT(rb_iv_get(self, "@hunk_index"));

	for (l = 0; l < lines_count; ++l) {
		const git_diff_line *line;
		error = git_patch_get_line_in_hunk(&line, patch, hunk_idx, l);
		if (error) break;

		rb_yield(rugged_diff_line_new(line));
	}
	rugged_exception_check(error);

	return self;
}

void Init_rugged_diff_hunk(void)
{
	rb_cRuggedDiffHunk = rb_define_class_under(rb_cRuggedDiff, "Hunk", rb_cObject);

	rb_include_module(rb_cRuggedDiffHunk, rb_mEnumerable);

	rb_define_method(rb_cRuggedDiffHunk, "each", rb_git_diff_hunk_each_line, 0);
	rb_define_method(rb_cRuggedDiffHunk, "each_line", rb_git_diff_hunk_each_line, 0);

	rb_define_attr(rb_cRuggedDiffHunk, "header", 1, 0);
	rb_define_attr(rb_cRuggedDiffHunk, "line_count", 1, 0);
	rb_define_attr(rb_cRuggedDiffHunk, "hunk_index", 1, 0);

	rb_define_attr(rb_cRuggedDiffHunk, "old_start", 1, 0);
	rb_define_attr(rb_cRuggedDiffHunk, "old_lines", 1, 0);
	rb_define_attr(rb_cRuggedDiffHunk, "new_start", 1, 0);
	rb_define_attr(rb_cRuggedDiffHunk, "new_lines", 1, 0);

	rb_define_alias(rb_cRuggedDiffHunk, "count", "line_count");
	rb_define_alias(rb_cRuggedDiffHunk, "size", "line_count");
}