#define USE_THE_REPOSITORY_VARIABLE

#include "git-compat-util.h"

#include "gettext.h"

#include "hex.h"

#include "odb.h"

#include "promisor-remote.h"

#include "config.h"

#include "trace2.h"

#include "transport.h"

#include "strvec.h"

#include "packfile.h"

#include "environment.h"

#include "url.h"

#include "version.h"

struct promisor_remote_config {

  struct promisor_remote *promisors;

  struct promisor_remote **promisors_tail;

};

static int fetch_objects(struct repository *repo,

       const char *remote_name,

       const struct object_id *oids,

       int oid_nr)

{

  struct child_process child = CHILD_PROCESS_INIT;

  int i;

  FILE *child_in;

  int quiet;

  if (git_env_bool(NO_LAZY_FETCH_ENVIRONMENT, 0)) {

    static int warning_shown;

    if (!warning_shown) {

      warning_shown = 1;

      warning(_("lazy fetching disabled; some objects may not be available"));

    }

    return -1;

  }

  child.git_cmd = 1;

  child.in = -1;

  if (repo != the_repository)

    prepare_other_repo_env(&child.env, repo->gitdir);

  strvec_pushl(&child.args, "-c", "fetch.negotiationAlgorithm=noop",

         "fetch", remote_name, "--no-tags",

         "--no-write-fetch-head", "--recurse-submodules=no",

         "--filter=blob:none", "--stdin", NULL);

  if (!repo_config_get_bool(the_repository, "promisor.quiet", &quiet) && quiet)

    strvec_push(&child.args, "--quiet");

  if (start_command(&child))

    die(_("promisor-remote: unable to fork off fetch subprocess"));

  child_in = xfdopen(child.in, "w");

  trace2_data_intmax("promisor", repo, "fetch_count", oid_nr);

  for (i = 0; i < oid_nr; i++) {

    if (fputs(oid_to_hex(&oids[i]), child_in) < 0)

      die_errno(_("promisor-remote: could not write to fetch subprocess"));

    if (fputc('\n', child_in) < 0)

      die_errno(_("promisor-remote: could not write to fetch subprocess"));

  }

  if (fclose(child_in) < 0)

    die_errno(_("promisor-remote: could not close stdin to fetch subprocess"));

  return finish_command(&child) ? -1 : 0;

}

static struct promisor_remote *promisor_remote_new(struct promisor_remote_config *config,

               const char *remote_name)

{

  struct promisor_remote *r;

  if (*remote_name == '/') {

    warning(_("promisor remote name cannot begin with '/': %s"),

      remote_name);

    return NULL;

  }

  FLEX_ALLOC_STR(r, name, remote_name);

  *config->promisors_tail = r;

  config->promisors_tail = &r->next;

  return r;

}

static struct promisor_remote *promisor_remote_lookup(struct promisor_remote_config *config,

                  const char *remote_name,

                  struct promisor_remote **previous)

{

  struct promisor_remote *r, *p;

  for (p = NULL, r = config->promisors; r; p = r, r = r->next)

    if (!strcmp(r->name, remote_name)) {

      if (previous)

        *previous = p;

      return r;

    }

  return NULL;

}

static void promisor_remote_move_to_tail(struct promisor_remote_config *config,

           struct promisor_remote *r,

           struct promisor_remote *previous)

{

  if (!r->next)

    return;

  if (previous)

    previous->next = r->next;

  else

    config->promisors = r->next ? r->next : r;

  r->next = NULL;

  *config->promisors_tail = r;

  config->promisors_tail = &r->next;

}

static int promisor_remote_config(const char *var, const char *value,

          const struct config_context *ctx UNUSED,

          void *data)

{

  struct promisor_remote_config *config = data;

  const char *name;

  size_t namelen;

  const char *subkey;

  if (parse_config_key(var, "remote", &name, &namelen, &subkey) < 0)

    return 0;

  if (!strcmp(subkey, "promisor")) {

    char *remote_name;

    if (!git_config_bool(var, value))

      return 0;

    remote_name = xmemdupz(name, namelen);

    if (!promisor_remote_lookup(config, remote_name, NULL))

      promisor_remote_new(config, remote_name);

    free(remote_name);

    return 0;

  }

  if (!strcmp(subkey, "partialclonefilter")) {

    struct promisor_remote *r;

    char *remote_name = xmemdupz(name, namelen);

    r = promisor_remote_lookup(config, remote_name, NULL);

    if (!r)

      r = promisor_remote_new(config, remote_name);

    free(remote_name);

    if (!r)

      return 0;

    FREE_AND_NULL(r->partial_clone_filter);

    return git_config_string(&r->partial_clone_filter, var, value);

  }

  return 0;

}

static void promisor_remote_init(struct repository *r)

{

  struct promisor_remote_config *config;

  if (r->promisor_remote_config)

    return;

  config = r->promisor_remote_config =

    xcalloc(1, sizeof(*r->promisor_remote_config));

  config->promisors_tail = &config->promisors;

  repo_config(r, promisor_remote_config, config);

  if (r->repository_format_partial_clone) {

    struct promisor_remote *o, *previous;

    o = promisor_remote_lookup(config,

             r->repository_format_partial_clone,

             &previous);

    if (o)

      promisor_remote_move_to_tail(config, o, previous);

    else

      promisor_remote_new(config, r->repository_format_partial_clone);

  }

}

void promisor_remote_clear(struct promisor_remote_config *config)

{

  while (config->promisors) {

    struct promisor_remote *r = config->promisors;

    free(r->partial_clone_filter);

    config->promisors = config->promisors->next;

    free(r);

  }

  config->promisors_tail = &config->promisors;

}

void repo_promisor_remote_reinit(struct repository *r)

{

  promisor_remote_clear(r->promisor_remote_config);

  FREE_AND_NULL(r->promisor_remote_config);

  promisor_remote_init(r);

}

struct promisor_remote *repo_promisor_remote_find(struct repository *r,

              const char *remote_name)

{

  promisor_remote_init(r);

  if (!remote_name)

    return r->promisor_remote_config->promisors;

  return promisor_remote_lookup(r->promisor_remote_config, remote_name, NULL);

}

int repo_has_promisor_remote(struct repository *r)

{

  return !!repo_promisor_remote_find(r, NULL);

}

int repo_has_accepted_promisor_remote(struct repository *r)

{

  struct promisor_remote *p;

  promisor_remote_init(r);

  for (p = r->promisor_remote_config->promisors; p; p = p->next)

    if (p->accepted)

      return 1;

  return 0;

}

static int remove_fetched_oids(struct repository *repo,

             struct object_id **oids,

             int oid_nr, int to_free)

{

  int i, remaining_nr = 0;

  int *remaining = xcalloc(oid_nr, sizeof(*remaining));

  struct object_id *old_oids = *oids;

  struct object_id *new_oids;

  for (i = 0; i < oid_nr; i++)

    if (odb_read_object_info_extended(repo->objects, &old_oids[i], NULL,

              OBJECT_INFO_SKIP_FETCH_OBJECT)) {

      remaining[i] = 1;

      remaining_nr++;

    }

  if (remaining_nr) {

    int j = 0;

    CALLOC_ARRAY(new_oids, remaining_nr);

    for (i = 0; i < oid_nr; i++)

      if (remaining[i])

        oidcpy(&new_oids[j++], &old_oids[i]);

    *oids = new_oids;

    if (to_free)

      free(old_oids);

  }

  free(remaining);

  return remaining_nr;

}

void promisor_remote_get_direct(struct repository *repo,

        const struct object_id *oids,

        int oid_nr)

{

  struct promisor_remote *r;

  struct object_id *remaining_oids = (struct object_id *)oids;

  int remaining_nr = oid_nr;

  int to_free = 0;

  int i;

  if (oid_nr == 0)

    return;

  promisor_remote_init(repo);

  for (r = repo->promisor_remote_config->promisors; r; r = r->next) {

    if (fetch_objects(repo, r->name, remaining_oids, remaining_nr) < 0) {

      if (remaining_nr == 1)

        continue;

      remaining_nr = remove_fetched_oids(repo, &remaining_oids,

               remaining_nr, to_free);

      if (remaining_nr) {

        to_free = 1;

        continue;

      }

    }

    goto all_fetched;

  }

  for (i = 0; i < remaining_nr; i++) {

    if (is_promisor_object(repo, &remaining_oids[i]))

      die(_("could not fetch %s from promisor remote"),

          oid_to_hex(&remaining_oids[i]));

  }

all_fetched:

  if (to_free)

    free(remaining_oids);

}

static int allow_unsanitized(char ch)

{

  if (ch == ',' || ch == ';' || ch == '%')

    return 0;

  return ch > 32 && ch < 127;

}

/*

 * All the fields used in "promisor-remote" protocol capability,

 * including the mandatory "name" and "url" ones.

 */

static const char promisor_field_name[] = "name";

static const char promisor_field_url[] = "url";

static const char promisor_field_filter[] = "partialCloneFilter";

static const char promisor_field_token[] = "token";

/*

 * List of optional field names that can be used in the

 * "promisor-remote" protocol capability (others must be

 * ignored). Each field should correspond to a configurable property

 * of a remote that can be relevant for the client.

 */

static const char *known_fields[] = {

  promisor_field_filter, /* Filter used for partial clone */

  promisor_field_token,  /* Authentication token for the remote */

  NULL

};

/*

 * Check if 'field' is in the list of the known field names for the

 * "promisor-remote" protocol capability.

 */

static int is_known_field(const char *field)

{

  const char **p;

  for (p = known_fields; *p; p++)

    if (!strcasecmp(*p, field))

      return 1;

  return 0;

}

static int is_valid_field(struct string_list_item *item, void *cb_data)

{

  const char *field = item->string;

  const char *config_key = (const char *)cb_data;

  if (!is_known_field(field)) {

    warning(_("unsupported field '%s' in '%s' config"), field, config_key);

    return 0;

  }

  return 1;

}

static char *fields_from_config(struct string_list *fields_list, const char *config_key)

{

  char *fields = NULL;

  if (!repo_config_get_string(the_repository, config_key, &fields) && *fields) {

    string_list_split_in_place_f(fields_list, fields, ",", -1,

               STRING_LIST_SPLIT_TRIM |

               STRING_LIST_SPLIT_NONEMPTY);

    filter_string_list(fields_list, 0, is_valid_field, (void *)config_key);

  }

  return fields;

}

static struct string_list *fields_sent(void)

{

  static struct string_list fields_list = STRING_LIST_INIT_NODUP;

  static int initialized;

  if (!initialized) {

    fields_list.cmp = strcasecmp;

    fields_from_config(&fields_list, "promisor.sendFields");

    initialized = 1;

  }

  return &fields_list;

}

static struct string_list *fields_checked(void)

{

  static struct string_list fields_list = STRING_LIST_INIT_NODUP;

  static int initialized;

  if (!initialized) {

    fields_list.cmp = strcasecmp;

    fields_from_config(&fields_list, "promisor.checkFields");

    initialized = 1;

  }

  return &fields_list;

}

/*

 * Struct for promisor remotes involved in the "promisor-remote"

 * protocol capability.

 *

 * Except for "name", each <member> in this struct and its <value>

 * should correspond (either on the client side or on the server side)

 * to a "remote.<name>.<member>" config variable set to <value> where

 * "<name>" is a promisor remote name.

 */

struct promisor_info {

  const char *name;

  const char *url;

  const char *filter;

  const char *token;

};

static void promisor_info_free(struct promisor_info *p)

{

  free((char *)p->name);

  free((char *)p->url);

  free((char *)p->filter);

  free((char *)p->token);

  free(p);

}

static void promisor_info_list_clear(struct string_list *list)

{

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

    promisor_info_free(list->items[i].util);

  string_list_clear(list, 0);

}

static void set_one_field(struct promisor_info *p,

        const char *field, const char *value)

{

  if (!strcasecmp(field, promisor_field_filter))

    p->filter = xstrdup(value);

  else if (!strcasecmp(field, promisor_field_token))

    p->token = xstrdup(value);

  else

    BUG("invalid field '%s'", field);

}

static void set_fields(struct promisor_info *p,

           struct string_list *field_names)

{

  struct string_list_item *item;

  for_each_string_list_item(item, field_names) {

    char *key = xstrfmt("remote.%s.%s", p->name, item->string);

    const char *val;

    if (!repo_config_get_string_tmp(the_repository, key, &val) && *val)

      set_one_field(p, item->string, val);

    free(key);

  }

}

/*

 * Populate 'list' with promisor remote information from the config.

 * The 'util' pointer of each list item will hold a 'struct

 * promisor_info'. Except "name" and "url", only members of that

 * struct specified by the 'field_names' list are set (using values

 * from the configuration).

 */

static void promisor_config_info_list(struct repository *repo,

              struct string_list *list,

              struct string_list *field_names)

{

  struct promisor_remote *r;

  promisor_remote_init(repo);

  for (r = repo->promisor_remote_config->promisors; r; r = r->next) {

    const char *url;

    char *url_key = xstrfmt("remote.%s.url", r->name);

    /* Only add remotes with a non empty URL */

    if (!repo_config_get_string_tmp(the_repository, url_key, &url) && *url) {

      struct promisor_info *new_info = xcalloc(1, sizeof(*new_info));

      struct string_list_item *item;

      new_info->name = xstrdup(r->name);

      new_info->url = xstrdup(url);

      if (field_names)

        set_fields(new_info, field_names);

      item = string_list_append(list, new_info->name);

      item->util = new_info;

    }

    free(url_key);

  }

}

char *promisor_remote_info(struct repository *repo)

{

  struct strbuf sb = STRBUF_INIT;

  int advertise_promisors = 0;

  struct string_list config_info = STRING_LIST_INIT_NODUP;

  struct string_list_item *item;

  repo_config_get_bool(the_repository, "promisor.advertise", &advertise_promisors);

  if (!advertise_promisors)

    return NULL;

  promisor_config_info_list(repo, &config_info, fields_sent());

  if (!config_info.nr)

    return NULL;

  for_each_string_list_item(item, &config_info) {

    struct promisor_info *p = item->util;

    if (item != config_info.items)

      strbuf_addch(&sb, ';');

    strbuf_addf(&sb, "%s=", promisor_field_name);

    strbuf_addstr_urlencode(&sb, p->name, allow_unsanitized);

    strbuf_addf(&sb, ",%s=", promisor_field_url);

    strbuf_addstr_urlencode(&sb, p->url, allow_unsanitized);

    if (p->filter) {

      strbuf_addf(&sb, ",%s=", promisor_field_filter);

      strbuf_addstr_urlencode(&sb, p->filter, allow_unsanitized);

    }

    if (p->token) {

      strbuf_addf(&sb, ",%s=", promisor_field_token);

      strbuf_addstr_urlencode(&sb, p->token, allow_unsanitized);

    }

  }

  promisor_info_list_clear(&config_info);

  return strbuf_detach(&sb, NULL);

}

enum accept_promisor {

  ACCEPT_NONE = 0,

  ACCEPT_KNOWN_URL,

  ACCEPT_KNOWN_NAME,

  ACCEPT_ALL

};

static int match_field_against_config(const char *field, const char *value,

              struct promisor_info *config_info)

{

  if (config_info->filter && !strcasecmp(field, promisor_field_filter))

    return !strcmp(config_info->filter, value);

  else if (config_info->token && !strcasecmp(field, promisor_field_token))

    return !strcmp(config_info->token, value);

  return 0;

}

static int all_fields_match(struct promisor_info *advertised,

          struct string_list *config_info,

          int in_list)

{

  struct string_list *fields = fields_checked();

  struct string_list_item *item_checked;

  for_each_string_list_item(item_checked, fields) {

    int match = 0;

    const char *field = item_checked->string;

    const char *value = NULL;

    struct string_list_item *item;

    if (!strcasecmp(field, promisor_field_filter))

      value = advertised->filter;

    else if (!strcasecmp(field, promisor_field_token))

      value = advertised->token;

    if (!value)

      return 0;

    if (in_list) {

      for_each_string_list_item(item, config_info) {

        struct promisor_info *p = item->util;

        if (match_field_against_config(field, value, p)) {

          match = 1;

          break;

        }

      }

    } else {

      item = string_list_lookup(config_info, advertised->name);

      if (item) {

        struct promisor_info *p = item->util;

        match = match_field_against_config(field, value, p);

      }

    }

    if (!match)

      return 0;

  }

  return 1;

}

static int should_accept_remote(enum accept_promisor accept,

        struct promisor_info *advertised,

        struct string_list *config_info)

{

  struct promisor_info *p;

  struct string_list_item *item;

  const char *remote_name = advertised->name;

  const char *remote_url = advertised->url;

  if (accept == ACCEPT_ALL)

    return all_fields_match(advertised, config_info, 1);

  /* Get config info for that promisor remote */

  item = string_list_lookup(config_info, remote_name);

  if (!item)

    /* We don't know about that remote */

    return 0;

  p = item->util;

  if (accept == ACCEPT_KNOWN_NAME)

    return all_fields_match(advertised, config_info, 0);

  if (accept != ACCEPT_KNOWN_URL)

    BUG("Unhandled 'enum accept_promisor' value '%d'", accept);

  if (!remote_url || !*remote_url) {

    warning(_("no or empty URL advertised for remote '%s'"), remote_name);

    return 0;

  }

  if (!strcmp(p->url, remote_url))

    return all_fields_match(advertised, config_info, 0);

  warning(_("known remote named '%s' but with URL '%s' instead of '%s'"),

    remote_name, p->url, remote_url);

  return 0;

}

static int skip_field_name_prefix(const char *elem, const char *field_name, const char **value)

{

  const char *p;

  if (!skip_prefix(elem, field_name, &p) || *p != '=')

    return 0;

  *value = p + 1;

  return 1;

}

static struct promisor_info *parse_one_advertised_remote(const char *remote_info)

{

  struct promisor_info *info = xcalloc(1, sizeof(*info));

  struct string_list elem_list = STRING_LIST_INIT_DUP;

  struct string_list_item *item;

  string_list_split(&elem_list, remote_info, ",", -1);

  for_each_string_list_item(item, &elem_list) {

    const char *elem = item->string;

    const char *p = strchr(elem, '=');

    if (!p) {

      warning(_("invalid element '%s' from remote info"), elem);

      continue;

    }

    if (skip_field_name_prefix(elem, promisor_field_name, &p))

      info->name = url_percent_decode(p);

    else if (skip_field_name_prefix(elem, promisor_field_url, &p))

      info->url = url_percent_decode(p);

    else if (skip_field_name_prefix(elem, promisor_field_filter, &p))

      info->filter = url_percent_decode(p);

    else if (skip_field_name_prefix(elem, promisor_field_token, &p))

      info->token = url_percent_decode(p);

  }

  string_list_clear(&elem_list, 0);

  if (!info->name || !info->url) {

    warning(_("server advertised a promisor remote without a name or URL: %s"),

      remote_info);

    promisor_info_free(info);

    return NULL;

  }

  return info;

}

static void filter_promisor_remote(struct repository *repo,

           struct strvec *accepted,

           const char *info)

{

  const char *accept_str;

  enum accept_promisor accept = ACCEPT_NONE;

  struct string_list config_info = STRING_LIST_INIT_NODUP;

  struct string_list remote_info = STRING_LIST_INIT_DUP;

  struct string_list_item *item;

  if (!repo_config_get_string_tmp(the_repository, "promisor.acceptfromserver", &accept_str)) {

    if (!*accept_str || !strcasecmp("None", accept_str))

      accept = ACCEPT_NONE;

    else if (!strcasecmp("KnownUrl", accept_str))

      accept = ACCEPT_KNOWN_URL;

    else if (!strcasecmp("KnownName", accept_str))

      accept = ACCEPT_KNOWN_NAME;

    else if (!strcasecmp("All", accept_str))

      accept = ACCEPT_ALL;

    else

      warning(_("unknown '%s' value for '%s' config option"),

        accept_str, "promisor.acceptfromserver");

  }

  if (accept == ACCEPT_NONE)

    return;

  /* Parse remote info received */

  string_list_split(&remote_info, info, ";", -1);

  for_each_string_list_item(item, &remote_info) {

    struct promisor_info *advertised;

    advertised = parse_one_advertised_remote(item->string);

    if (!advertised)

      continue;

    if (!config_info.nr) {

      promisor_config_info_list(repo, &config_info, fields_checked());

      string_list_sort(&config_info);

    }

    if (should_accept_remote(accept, advertised, &config_info))

      strvec_push(accepted, advertised->name);

    promisor_info_free(advertised);

  }

  promisor_info_list_clear(&config_info);

  string_list_clear(&remote_info, 0);

}

char *promisor_remote_reply(const char *info)

{

  struct strvec accepted = STRVEC_INIT;

  struct strbuf reply = STRBUF_INIT;

  filter_promisor_remote(the_repository, &accepted, info);

  if (!accepted.nr)

    return NULL;

  for (size_t i = 0; i < accepted.nr; i++) {

    if (i)

      strbuf_addch(&reply, ';');

    strbuf_addstr_urlencode(&reply, accepted.v[i], allow_unsanitized);

  }

  strvec_clear(&accepted);

  return strbuf_detach(&reply, NULL);

}

void mark_promisor_remotes_as_accepted(struct repository *r, const char *remotes)

{

  struct string_list accepted_remotes = STRING_LIST_INIT_DUP;

  struct string_list_item *item;

  string_list_split(&accepted_remotes, remotes, ";", -1);

  for_each_string_list_item(item, &accepted_remotes) {

    char *decoded_remote = url_percent_decode(item->string);

    struct promisor_remote *p = repo_promisor_remote_find(r, decoded_remote);

    if (p)

      p->accepted = 1;

    else

      warning(_("accepted promisor remote '%s' not found"),

        decoded_remote);

    free(decoded_remote);

  }

  string_list_clear(&accepted_remotes, 0);

}