#include "builtin.h"

#include "hex.h"

#include "read-cache-ll.h"

#include "repository.h"

#include "run-command.h"

#include "sparse-index.h"

static const char *pgm;

static int one_shot, quiet;

static int err;

static int merge_entry(int pos, const char *path)

{

  int found;

  const char *arguments[] = { pgm, "", "", "", path, "", "", "", NULL };

  char hexbuf[4][GIT_MAX_HEXSZ + 1];

  char ownbuf[4][60];

  struct child_process cmd = CHILD_PROCESS_INIT;

  if (pos >= the_repository->index->cache_nr)

    die("git merge-index: %s not in the cache", path);

  found = 0;

  do {

    const struct cache_entry *ce = the_repository->index->cache[pos];

    int stage = ce_stage(ce);

    if (strcmp(ce->name, path))

      break;

    found++;

    oid_to_hex_r(hexbuf[stage], &ce->oid);

    xsnprintf(ownbuf[stage], sizeof(ownbuf[stage]), "%o", ce->ce_mode);

    arguments[stage] = hexbuf[stage];

    arguments[stage + 4] = ownbuf[stage];

  } while (++pos < the_repository->index->cache_nr);

  if (!found)

    die("git merge-index: %s not in the cache", path);

  strvec_pushv(&cmd.args, arguments);

  if (run_command(&cmd)) {

    if (one_shot)

      err++;

    else {

      if (!quiet)

        die("merge program failed");

      exit(1);

    }

  }

  return found;

}

static void merge_one_path(const char *path)

{

  int pos = index_name_pos(the_repository->index, path, strlen(path));

  /*

   * If it already exists in the cache as stage0, it's

   * already merged and there is nothing to do.

   */

  if (pos < 0)

    merge_entry(-pos-1, path);

}

static void merge_all(void)

{

  int i;

  /* TODO: audit for interaction with sparse-index. */

  ensure_full_index(the_repository->index);

  for (i = 0; i < the_repository->index->cache_nr; i++) {

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

    if (!ce_stage(ce))

      continue;

    i += merge_entry(i, ce->name)-1;

  }

}

int cmd_merge_index(int argc, const char **argv, const char *prefix UNUSED)

{

  int i, force_file = 0;

  /* Without this we cannot rely on waitpid() to tell

   * what happened to our children.

   */

  signal(SIGCHLD, SIG_DFL);

  if (argc < 3)

    usage("git merge-index [-o] [-q] <merge-program> (-a | [--] [<filename>...])");

  repo_read_index(the_repository);

  /* TODO: audit for interaction with sparse-index. */

  ensure_full_index(the_repository->index);

  i = 1;

  if (!strcmp(argv[i], "-o")) {

    one_shot = 1;

    i++;

  }

  if (!strcmp(argv[i], "-q")) {

    quiet = 1;

    i++;

  }

  pgm = argv[i++];

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

    const char *arg = argv[i];

    if (!force_file && *arg == '-') {

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

        force_file = 1;

        continue;

      }

      if (!strcmp(arg, "-a")) {

        merge_all();

        continue;

      }

      die("git merge-index: unknown option %s", arg);

    }

    merge_one_path(arg);

  }

  if (err && !quiet)

    die("merge program failed");

  return err;

}