#define USE_THE_REPOSITORY_VARIABLE

#include "git-compat-util.h"

#include "commit.h"

#include "refs.h"

#include "diff.h"

#include "repository.h"

#include "revision.h"

#include "string-list.h"

#include "reflog-walk.h"

struct complete_reflogs {

  char *ref;

  char *short_ref;

  struct reflog_info {

    struct object_id ooid, noid;

    char *email;

    timestamp_t timestamp;

    int tz;

    char *message;

  } *items;

  int nr, alloc;

};

static int read_one_reflog(struct object_id *ooid, struct object_id *noid,

    const char *email, timestamp_t timestamp, int tz,

    const char *message, void *cb_data)

{

  struct complete_reflogs *array = cb_data;

  struct reflog_info *item;

  ALLOC_GROW(array->items, array->nr + 1, array->alloc);

  item = array->items + array->nr;

  oidcpy(&item->ooid, ooid);

  oidcpy(&item->noid, noid);

  item->email = xstrdup(email);

  item->timestamp = timestamp;

  item->tz = tz;

  item->message = xstrdup(message);

  array->nr++;

  return 0;

}

static void free_complete_reflog(struct complete_reflogs *array)

{

  int i;

  if (!array)

    return;

  for (i = 0; i < array->nr; i++) {

    free(array->items[i].email);

    free(array->items[i].message);

  }

  free(array->items);

  free(array->ref);

  free(array->short_ref);

  free(array);

}

static void complete_reflogs_clear(void *util, const char *str UNUSED)

{

  struct complete_reflogs *array = util;

  free_complete_reflog(array);

}

static struct complete_reflogs *read_complete_reflog(const char *ref)

{

  struct complete_reflogs *reflogs =

    xcalloc(1, sizeof(struct complete_reflogs));

  reflogs->ref = xstrdup(ref);

  refs_for_each_reflog_ent(get_main_ref_store(the_repository), ref,

         read_one_reflog, reflogs);

  if (reflogs->nr == 0) {

    const char *name;

    void *name_to_free;

    name = name_to_free = refs_resolve_refdup(get_main_ref_store(the_repository),

                ref,

                RESOLVE_REF_READING,

                NULL, NULL);

    if (name) {

      refs_for_each_reflog_ent(get_main_ref_store(the_repository),

             name, read_one_reflog,

             reflogs);

      free(name_to_free);

    }

  }

  if (reflogs->nr == 0) {

    char *refname = xstrfmt("refs/%s", ref);

    refs_for_each_reflog_ent(get_main_ref_store(the_repository),

           refname, read_one_reflog, reflogs);

    if (reflogs->nr == 0) {

      free(refname);

      refname = xstrfmt("refs/heads/%s", ref);

      refs_for_each_reflog_ent(get_main_ref_store(the_repository),

             refname, read_one_reflog,

             reflogs);

    }

    free(refname);

  }

  return reflogs;

}

static int get_reflog_recno_by_time(struct complete_reflogs *array,

  timestamp_t timestamp)

{

  int i;

  for (i = array->nr - 1; i >= 0; i--)

    if (timestamp >= array->items[i].timestamp)

      return i;

  return -1;

}

struct commit_reflog {

  int recno;

  enum selector_type {

    SELECTOR_NONE,

    SELECTOR_INDEX,

    SELECTOR_DATE

  } selector;

  struct complete_reflogs *reflogs;

};

struct reflog_walk_info {

  struct commit_reflog **logs;

  size_t nr, alloc;

  struct string_list complete_reflogs;

  struct commit_reflog *last_commit_reflog;

};

void init_reflog_walk(struct reflog_walk_info **info)

{

  CALLOC_ARRAY(*info, 1);

  (*info)->complete_reflogs.strdup_strings = 1;

}

void reflog_walk_info_release(struct reflog_walk_info *info)

{

  size_t i;

  if (!info)

    return;

  for (i = 0; i < info->nr; i++)

    free(info->logs[i]);

  string_list_clear_func(&info->complete_reflogs,

             complete_reflogs_clear);

  free(info->logs);

  free(info);

}

int add_reflog_for_walk(struct reflog_walk_info *info,

    struct commit *commit, const char *name)

{

  timestamp_t timestamp = 0;

  int recno = -1;

  struct string_list_item *item;

  struct complete_reflogs *reflogs;

  char *branch, *at = strchr(name, '@');

  struct commit_reflog *commit_reflog;

  enum selector_type selector = SELECTOR_NONE;

  if (commit->object.flags & UNINTERESTING)

    die("cannot walk reflogs for %s", name);

  branch = xstrdup(name);

  if (at && at[1] == '{') {

    char *ep;

    branch[at - name] = '\0';

    recno = strtoul(at + 2, &ep, 10);

    if (*ep != '}') {

      recno = -1;

      timestamp = approxidate(at + 2);

      selector = SELECTOR_DATE;

    }

    else

      selector = SELECTOR_INDEX;

  } else

    recno = 0;

  item = string_list_lookup(&info->complete_reflogs, branch);

  if (item)

    reflogs = item->util;

  else {

    if (*branch == '\0') {

      free(branch);

      branch = refs_resolve_refdup(get_main_ref_store(the_repository),

                 "HEAD", 0, NULL, NULL);

      if (!branch)

        die("no current branch");

    }

    reflogs = read_complete_reflog(branch);

    if (!reflogs || reflogs->nr == 0) {

      char *b;

      int ret = repo_dwim_log(the_repository, branch, strlen(branch),

            NULL, &b);

      if (ret > 1)

        free(b);

      else if (ret == 1) {

        free_complete_reflog(reflogs);

        free(branch);

        branch = b;

        reflogs = read_complete_reflog(branch);

      }

    }

    if (!reflogs || reflogs->nr == 0) {

      free_complete_reflog(reflogs);

      free(branch);

      return -1;

    }

    string_list_insert(&info->complete_reflogs, branch)->util

      = reflogs;

  }

  free(branch);

  CALLOC_ARRAY(commit_reflog, 1);

  if (recno < 0) {

    commit_reflog->recno = get_reflog_recno_by_time(reflogs, timestamp);

    if (commit_reflog->recno < 0) {

      free(commit_reflog);

      return -1;

    }

  } else

    commit_reflog->recno = reflogs->nr - recno - 1;

  commit_reflog->selector = selector;

  commit_reflog->reflogs = reflogs;

  ALLOC_GROW(info->logs, info->nr + 1, info->alloc);

  info->logs[info->nr++] = commit_reflog;

  return 0;

}

void get_reflog_selector(struct strbuf *sb,

       struct reflog_walk_info *reflog_info,

       struct date_mode dmode, int force_date,

       int shorten)

{

  struct commit_reflog *commit_reflog = reflog_info->last_commit_reflog;

  struct reflog_info *info;

  const char *printed_ref;

  if (!commit_reflog)

    return;

  if (shorten) {

    if (!commit_reflog->reflogs->short_ref)

      commit_reflog->reflogs->short_ref

        = refs_shorten_unambiguous_ref(get_main_ref_store(the_repository),

                     commit_reflog->reflogs->ref,

                     0);

    printed_ref = commit_reflog->reflogs->short_ref;

  } else {

    printed_ref = commit_reflog->reflogs->ref;

  }

  strbuf_addf(sb, "%s@{", printed_ref);

  if (commit_reflog->selector == SELECTOR_DATE ||

      (commit_reflog->selector == SELECTOR_NONE && force_date)) {

    info = &commit_reflog->reflogs->items[commit_reflog->recno+1];

    strbuf_addstr(sb, show_date(info->timestamp, info->tz, dmode));

  } else {

    strbuf_addf(sb, "%d", commit_reflog->reflogs->nr

          - 2 - commit_reflog->recno);

  }

  strbuf_addch(sb, '}');

}

void get_reflog_message(struct strbuf *sb,

      struct reflog_walk_info *reflog_info)

{

  struct commit_reflog *commit_reflog = reflog_info->last_commit_reflog;

  struct reflog_info *info;

  size_t len;

  if (!commit_reflog)

    return;

  info = &commit_reflog->reflogs->items[commit_reflog->recno+1];

  len = strlen(info->message);

  if (len > 0)

    len--; /* strip away trailing newline */

  strbuf_add(sb, info->message, len);

}

const char *get_reflog_ident(struct reflog_walk_info *reflog_info)

{

  struct commit_reflog *commit_reflog = reflog_info->last_commit_reflog;

  struct reflog_info *info;

  if (!commit_reflog)

    return NULL;

  info = &commit_reflog->reflogs->items[commit_reflog->recno+1];

  return info->email;

}

timestamp_t get_reflog_timestamp(struct reflog_walk_info *reflog_info)

{

  struct commit_reflog *commit_reflog = reflog_info->last_commit_reflog;

  struct reflog_info *info;

  if (!commit_reflog)

    return 0;

  info = &commit_reflog->reflogs->items[commit_reflog->recno+1];

  return info->timestamp;

}

void show_reflog_message(struct reflog_walk_info *reflog_info, int oneline,

       struct date_mode dmode, int force_date)

{

  if (reflog_info && reflog_info->last_commit_reflog) {

    struct commit_reflog *commit_reflog = reflog_info->last_commit_reflog;

    struct reflog_info *info;

    struct strbuf selector = STRBUF_INIT;

    info = &commit_reflog->reflogs->items[commit_reflog->recno+1];

    get_reflog_selector(&selector, reflog_info, dmode, force_date, 0);

    if (oneline) {

      printf("%s: %s", selector.buf, info->message);

    }

    else {

      printf("Reflog: %s (%s)\nReflog message: %s",

             selector.buf, info->email, info->message);

    }

    strbuf_release(&selector);

  }

}

int reflog_walk_empty(struct reflog_walk_info *info)

{

  return !info || !info->nr;

}

static struct commit *next_reflog_commit(struct commit_reflog *log)

{

  for (; log->recno >= 0; log->recno--) {

    struct reflog_info *entry = &log->reflogs->items[log->recno];

    struct object *obj = parse_object(the_repository,

              &entry->noid);

    if (obj && obj->type == OBJ_COMMIT)

      return (struct commit *)obj;

  }

  return NULL;

}

static timestamp_t log_timestamp(struct commit_reflog *log)

{

  return log->reflogs->items[log->recno].timestamp;

}

struct commit *next_reflog_entry(struct reflog_walk_info *walk)

{

  struct commit_reflog *best = NULL;

  struct commit *best_commit = NULL;

  size_t i;

  for (i = 0; i < walk->nr; i++) {

    struct commit_reflog *log = walk->logs[i];

    struct commit *commit = next_reflog_commit(log);

    if (!commit)

      continue;

    if (!best || log_timestamp(log) > log_timestamp(best)) {

      best = log;

      best_commit = commit;

    }

  }

  if (best) {

    best->recno--;

    walk->last_commit_reflog = best;

    return best_commit;

  }

  return NULL;

}