#include "builtin.h"

#include "config.h"

#include "diff.h"

#include "diff-merges.h"

#include "commit.h"

#include "preload-index.h"

#include "repository.h"

#include "revision.h"

#include "setup.h"

static const char diff_cache_usage[] =

"git diff-index [-m] [--cached] [--merge-base] "

"[<common-diff-options>] <tree-ish> [<path>...]"

"\n"

COMMON_DIFF_OPTIONS_HELP;

int cmd_diff_index(int argc, const char **argv, const char *prefix)

{

  struct rev_info rev;

  unsigned int option = 0;

  int i;

  int result;

  if (argc == 2 && !strcmp(argv[1], "-h"))

    usage(diff_cache_usage);

  git_config(git_diff_basic_config, NULL); /* no "diff" UI options */

  prepare_repo_settings(the_repository);

  the_repository->settings.command_requires_full_index = 0;

  repo_init_revisions(the_repository, &rev, prefix);

  rev.abbrev = 0;

  prefix = precompose_argv_prefix(argc, argv, prefix);

  /*

   * We need (some of) diff for merges options (e.g., --cc), and we need

   * to avoid conflict with our own meaning of "-m".

   */

  diff_merges_suppress_m_parsing();

  argc = setup_revisions(argc, argv, &rev, NULL);

  for (i = 1; i < argc; i++) {

    const char *arg = argv[i];

    if (!strcmp(arg, "--cached"))

      option |= DIFF_INDEX_CACHED;

    else if (!strcmp(arg, "--merge-base"))

      option |= DIFF_INDEX_MERGE_BASE;

    else if (!strcmp(arg, "-m"))

      rev.match_missing = 1;

    else

      usage(diff_cache_usage);

  }

  if (!rev.diffopt.output_format)

    rev.diffopt.output_format = DIFF_FORMAT_RAW;

  rev.diffopt.rotate_to_strict = 1;

  /*

   * Make sure there is one revision (i.e. pending object),

   * and there is no revision filtering parameters.

   */

  if (rev.pending.nr != 1 ||

      rev.max_count != -1 || rev.min_age != -1 || rev.max_age != -1)

    usage(diff_cache_usage);

  if (!(option & DIFF_INDEX_CACHED)) {

    setup_work_tree();

    if (repo_read_index_preload(the_repository, &rev.diffopt.pathspec, 0) < 0) {

      perror("repo_read_index_preload");

      return -1;

    }

  } else if (repo_read_index(the_repository) < 0) {

    perror("repo_read_index");

    return -1;

  }

  run_diff_index(&rev, option);

  result = diff_result_code(&rev.diffopt);

  release_revisions(&rev);

  return result;

}