/*
 * adm_files.c: helper routines for handling files & dirs in the
 *              working copy administrative area (creating,
 *              deleting, opening, and closing).  This is the only
 *              code that actually knows where administrative
 *              information is kept.
 *
 * ====================================================================
 *    Licensed to the Apache Software Foundation (ASF) under one
 *    or more contributor license agreements.  See the NOTICE file
 *    distributed with this work for additional information
 *    regarding copyright ownership.  The ASF licenses this file
 *    to you under the Apache License, Version 2.0 (the
 *    "License"); you may not use this file except in compliance
 *    with the License.  You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 *    Unless required by applicable law or agreed to in writing,
 *    software distributed under the License is distributed on an
 *    "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 *    KIND, either express or implied.  See the License for the
 *    specific language governing permissions and limitations
 *    under the License.
 * ====================================================================
 */


#include <stdarg.h>
#include <apr_pools.h>
#include <apr_file_io.h>
#include <apr_strings.h>

#include "svn_types.h"
#include "svn_error.h"
#include "svn_io.h"
#include "svn_dirent_uri.h"
#include "svn_path.h"
#include "svn_hash.h"

#include "wc.h"
#include "adm_files.h"
#include "entries.h"
#include "lock.h"

#include "svn_private_config.h"
#include "private/svn_wc_private.h"


/*** File names in the adm area. ***/

/* The default name of the WC admin directory. This name is always
   checked by svn_wc_is_adm_dir. */
static const char default_adm_dir_name[] = ".svn";

/* The name that is actually used for the WC admin directory.  The
   commonest case where this won't be the default is in Windows
   ASP.NET development environments, which used to choke on ".svn". */
static const char *adm_dir_name = default_adm_dir_name;


svn_boolean_t
svn_wc_is_adm_dir(const char *name, apr_pool_t *pool)
{
  return (0 == strcmp(name, adm_dir_name)
          || 0 == strcmp(name, default_adm_dir_name));
}


const char *
svn_wc_get_adm_dir(apr_pool_t *pool)
{
  return adm_dir_name;
}


svn_error_t *
svn_wc_set_adm_dir(const char *name, apr_pool_t *pool)
{
  /* This is the canonical list of administrative directory names.

     FIXME:
     An identical list is used in
       libsvn_subr/opt.c:svn_opt__args_to_target_array(),
     but that function can't use this list, because that use would
     create a circular dependency between libsvn_wc and libsvn_subr.
     Make sure changes to the lists are always synchronized! */
  static const char *valid_dir_names[] = {
    default_adm_dir_name,
    "_svn",
    NULL
  };

  const char **dir_name;
  for (dir_name = valid_dir_names; *dir_name; ++dir_name)
    if (0 == strcmp(name, *dir_name))
      {
        /* Use the pointer to the statically allocated string
           constant, to avoid potential pool lifetime issues. */
        adm_dir_name = *dir_name;
        return SVN_NO_ERROR;
      }
  return svn_error_createf(SVN_ERR_BAD_FILENAME, NULL,
                           _("'%s' is not a valid administrative "
                             "directory name"),
                           svn_dirent_local_style(name, pool));
}


const char *
svn_wc__adm_child(const char *path,
                  const char *child,
                  apr_pool_t *result_pool)
{
  return svn_dirent_join_many(result_pool,
                              path,
                              adm_dir_name,
                              child,
                              SVN_VA_NULL);
}


svn_boolean_t
svn_wc__adm_area_exists(const char *adm_abspath,
                        apr_pool_t *pool)
{
  const char *path = svn_wc__adm_child(adm_abspath, NULL, pool);
  svn_node_kind_t kind;
  svn_error_t *err;

  err = svn_io_check_path(path, &kind, pool);
  if (err)
    {
      svn_error_clear(err);
      /* Return early, since kind is undefined in this case. */
      return FALSE;
    }

  return kind != svn_node_none;
}


/*** Making and using files in the adm area. ***/


/* */
static svn_error_t *
make_adm_subdir(const char *path,
                const char *subdir,
                apr_pool_t *pool)
{
  const char *fullpath;

  fullpath = svn_wc__adm_child(path, subdir, pool);

  return svn_io_dir_make(fullpath, APR_OS_DEFAULT, pool);
}


/*** Syncing files in the adm area. ***/


svn_error_t *
svn_wc__text_base_path_to_read(const char **result_abspath,
                               svn_wc__db_t *db,
                               const char *local_abspath,
                               apr_pool_t *result_pool,
                               apr_pool_t *scratch_pool)
{
  svn_wc__db_status_t status;
  svn_node_kind_t kind;
  const svn_checksum_t *checksum;

  SVN_ERR(svn_wc__db_read_pristine_info(&status, &kind, NULL, NULL, NULL, NULL,
                                        &checksum, NULL, NULL, NULL,
                                        db, local_abspath,
                                        scratch_pool, scratch_pool));

  /* Sanity */
  if (kind != svn_node_file)
    return svn_error_createf(SVN_ERR_NODE_UNEXPECTED_KIND, NULL,
                             _("Can only get the pristine contents of files; "
                               "'%s' is not a file"),
                             svn_dirent_local_style(local_abspath,
                                                    scratch_pool));

  if (status == svn_wc__db_status_not_present)
    /* We know that the delete of this node has been committed.
       This should be the same as if called on an unknown path. */
    return svn_error_createf(SVN_ERR_WC_PATH_NOT_FOUND, NULL,
                             _("Cannot get the pristine contents of '%s' "
                               "because its delete is already committed"),
                             svn_dirent_local_style(local_abspath,
                                                    scratch_pool));
  else if (status == svn_wc__db_status_server_excluded
      || status == svn_wc__db_status_excluded
      || status == svn_wc__db_status_incomplete)
    return svn_error_createf(SVN_ERR_WC_PATH_UNEXPECTED_STATUS, NULL,
                             _("Cannot get the pristine contents of '%s' "
                               "because it has an unexpected status"),
                             svn_dirent_local_style(local_abspath,
                                                    scratch_pool));

  if (checksum == NULL)
    return svn_error_createf(SVN_ERR_WC_PATH_UNEXPECTED_STATUS, NULL,
                             _("Node '%s' has no pristine text"),
                             svn_dirent_local_style(local_abspath,
                                                    scratch_pool));
  SVN_ERR(svn_wc__db_pristine_get_path(result_abspath, db, local_abspath,
                                       checksum,
                                       result_pool, scratch_pool));
  return SVN_NO_ERROR;
}

svn_error_t *
svn_wc__get_pristine_contents(svn_stream_t **contents,
                              svn_filesize_t *size,
                              svn_wc__db_t *db,
                              const char *local_abspath,
                              apr_pool_t *result_pool,
                              apr_pool_t *scratch_pool)
{
  svn_wc__db_status_t status;
  svn_node_kind_t kind;
  const svn_checksum_t *sha1_checksum;

  if (size)
    *size = SVN_INVALID_FILESIZE;

  SVN_ERR(svn_wc__db_read_pristine_info(&status, &kind, NULL, NULL, NULL, NULL,
                                        &sha1_checksum, NULL, NULL, NULL,
                                        db, local_abspath,
                                        scratch_pool, scratch_pool));

  /* Sanity */
  if (kind != svn_node_file)
    return svn_error_createf(SVN_ERR_NODE_UNEXPECTED_KIND, NULL,
                             _("Can only get the pristine contents of files; "
                               "'%s' is not a file"),
                             svn_dirent_local_style(local_abspath,
                                                    scratch_pool));

  if (status == svn_wc__db_status_added && !sha1_checksum)
    {
      /* Simply added. The pristine base does not exist. */
      *contents = NULL;
      return SVN_NO_ERROR;
    }
  else if (status == svn_wc__db_status_not_present)
    /* We know that the delete of this node has been committed.
       This should be the same as if called on an unknown path. */
    return svn_error_createf(SVN_ERR_WC_PATH_NOT_FOUND, NULL,
                             _("Cannot get the pristine contents of '%s' "
                               "because its delete is already committed"),
                             svn_dirent_local_style(local_abspath,
                                                    scratch_pool));
  else if (status == svn_wc__db_status_server_excluded
      || status == svn_wc__db_status_excluded
      || status == svn_wc__db_status_incomplete)
    return svn_error_createf(SVN_ERR_WC_PATH_UNEXPECTED_STATUS, NULL,
                             _("Cannot get the pristine contents of '%s' "
                               "because it has an unexpected status"),
                             svn_dirent_local_style(local_abspath,
                                                    scratch_pool));
  if (sha1_checksum)
    SVN_ERR(svn_wc__db_pristine_read(contents, size, db, local_abspath,
                                     sha1_checksum,
                                     result_pool, scratch_pool));
  else
    *contents = NULL;

  return SVN_NO_ERROR;
}


/*** Opening and closing files in the adm area. ***/

svn_error_t *
svn_wc__open_adm_stream(svn_stream_t **stream,
                        const char *dir_abspath,
                        const char *fname,
                        apr_pool_t *result_pool,
                        apr_pool_t *scratch_pool)
{
  const char *local_abspath;

  SVN_ERR_ASSERT(svn_dirent_is_absolute(dir_abspath));

  local_abspath = svn_wc__adm_child(dir_abspath, fname, scratch_pool);
  return svn_error_trace(svn_stream_open_readonly(stream, local_abspath,
                                                  result_pool, scratch_pool));
}


/*** Checking for and creating administrative subdirs. ***/


/* */
static svn_error_t *
init_adm_tmp_area(const char *path, apr_pool_t *pool)
{
  /* SVN_WC__ADM_TMP */
  SVN_ERR(make_adm_subdir(path, SVN_WC__ADM_TMP, pool));

  return SVN_NO_ERROR;
}


/* Set up a new adm area for PATH, with REPOS_* as the repos info, and
   INITIAL_REV as the starting revision.  The entries file starts out
   marked as 'incomplete.  The adm area starts out locked; remember to
   unlock it when done. */
static svn_error_t *
init_adm(svn_wc__db_t *db,
         const char *local_abspath,
         const char *repos_relpath,
         const char *repos_root_url,
         const char *repos_uuid,
         svn_revnum_t initial_rev,
         svn_depth_t depth,
         apr_pool_t *pool)
{
  /* First, make an empty administrative area. */
  SVN_ERR(svn_io_dir_make_hidden(svn_wc__adm_child(local_abspath, NULL, pool),
                                 APR_OS_DEFAULT, pool));

  /** Make subdirectories. ***/

  /* SVN_WC__ADM_PRISTINE */
  SVN_ERR(make_adm_subdir(local_abspath, SVN_WC__ADM_PRISTINE, pool));

  /* ### want to add another directory? do a format bump to ensure that
     ### all existing working copies get the new directories. or maybe
     ### create-on-demand (more expensive)  */

  /** Init the tmp area. ***/
  SVN_ERR(init_adm_tmp_area(local_abspath, pool));

  /* Create the SDB. */
  SVN_ERR(svn_wc__db_init(db, local_abspath,
                          repos_relpath, repos_root_url, repos_uuid,
                          initial_rev, depth,
                          pool));

  /* Stamp ENTRIES and FORMAT files for old clients.  */
  SVN_ERR(svn_io_file_create(svn_wc__adm_child(local_abspath,
                                               SVN_WC__ADM_ENTRIES,
                                               pool),
                             SVN_WC__NON_ENTRIES_STRING,
                             pool));
  SVN_ERR(svn_io_file_create(svn_wc__adm_child(local_abspath,
                                               SVN_WC__ADM_FORMAT,
                                               pool),
                             SVN_WC__NON_ENTRIES_STRING,
                             pool));

  return SVN_NO_ERROR;
}

svn_error_t *
svn_wc__internal_ensure_adm(svn_wc__db_t *db,
                            const char *local_abspath,
                            const char *url,
                            const char *repos_root_url,
                            const char *repos_uuid,
                            svn_revnum_t revision,
                            svn_depth_t depth,
                            apr_pool_t *scratch_pool)
{
  int format;
  const char *original_repos_relpath;
  const char *original_root_url;
  svn_boolean_t is_op_root;
  const char *repos_relpath = svn_uri_skip_ancestor(repos_root_url, url,
                                                    scratch_pool);
  svn_wc__db_status_t status;
  const char *db_repos_relpath, *db_repos_root_url, *db_repos_uuid;
  svn_revnum_t db_revision;

  SVN_ERR_ASSERT(svn_dirent_is_absolute(local_abspath));
  SVN_ERR_ASSERT(url != NULL);
  SVN_ERR_ASSERT(repos_root_url != NULL);
  SVN_ERR_ASSERT(repos_uuid != NULL);
  SVN_ERR_ASSERT(repos_relpath != NULL);

  SVN_ERR(svn_wc__internal_check_wc(&format, db, local_abspath, TRUE,
                                    scratch_pool));

  /* Early out: we know we're not dealing with an existing wc, so
     just create one. */
  if (format == 0)
    return svn_error_trace(init_adm(db, local_abspath,
                                    repos_relpath, repos_root_url, repos_uuid,
                                    revision, depth, scratch_pool));

  SVN_ERR(svn_wc__db_read_info(&status, NULL,
                               &db_revision, &db_repos_relpath,
                               &db_repos_root_url, &db_repos_uuid,
                               NULL, NULL, NULL, NULL, NULL, NULL,
                               &original_repos_relpath, &original_root_url,
                               NULL, NULL, NULL, NULL, NULL, NULL,
                               NULL, &is_op_root, NULL, NULL,
                               NULL, NULL, NULL,
                               db, local_abspath, scratch_pool, scratch_pool));

  /* When the directory exists and is scheduled for deletion or is not-present
   * do not check the revision or the URL.  The revision can be any
   * arbitrary revision and the URL may differ if the add is
   * being driven from a merge which will have a different URL. */
  if (status != svn_wc__db_status_deleted
      && status != svn_wc__db_status_not_present)
    {
      /* ### Should we match copyfrom_revision? */
      if (db_revision != revision)
        return
          svn_error_createf(SVN_ERR_WC_OBSTRUCTED_UPDATE, NULL,
                            _("Revision %ld doesn't match existing "
                              "revision %ld in '%s'"),
                            revision, db_revision, local_abspath);

      if (!db_repos_root_url)
        {
          if (status == svn_wc__db_status_added)
            SVN_ERR(svn_wc__db_scan_addition(NULL, NULL,
                                             &db_repos_relpath,
                                             &db_repos_root_url,
                                             &db_repos_uuid,
                                             NULL, NULL, NULL, NULL,
                                             db, local_abspath,
                                             scratch_pool, scratch_pool));
          else
            SVN_ERR(svn_wc__db_base_get_info(NULL, NULL, NULL,
                                             &db_repos_relpath,
                                             &db_repos_root_url,
                                             &db_repos_uuid, NULL, NULL, NULL,
                                             NULL, NULL, NULL, NULL, NULL,
                                             NULL, NULL,
                                             db, local_abspath,
                                             scratch_pool, scratch_pool));
        }

      /* The caller gives us a URL which should match the entry. However,
         some callers compensate for an old problem in entry->url and pass
         the copyfrom_url instead. See ^/notes/api-errata/1.7/wc002.txt. As
         a result, we allow the passed URL to match copyfrom_url if it
         does not match the entry's primary URL.  */
      if (strcmp(db_repos_uuid, repos_uuid)
          || strcmp(db_repos_root_url, repos_root_url)
          || !svn_relpath_skip_ancestor(db_repos_relpath, repos_relpath))
        {
          if (!is_op_root /* copy_from was set on op-roots only */
              || original_root_url == NULL
              || strcmp(original_root_url, repos_root_url)
              || strcmp(original_repos_relpath, repos_relpath))
            return
              svn_error_createf(SVN_ERR_WC_OBSTRUCTED_UPDATE, NULL,
                                _("URL '%s' (uuid: '%s') doesn't match existing "
                                  "URL '%s' (uuid: '%s') in '%s'"),
                                url,
                                db_repos_uuid,
                                svn_path_url_add_component2(db_repos_root_url,
                                                            db_repos_relpath,
                                                            scratch_pool),
                                repos_uuid,
                                local_abspath);
        }
    }

  return SVN_NO_ERROR;
}

svn_error_t *
svn_wc_ensure_adm4(svn_wc_context_t *wc_ctx,
                   const char *local_abspath,
                   const char *url,
                   const char *repos_root_url,
                   const char *repos_uuid,
                   svn_revnum_t revision,
                   svn_depth_t depth,
                   apr_pool_t *scratch_pool)
{
  return svn_error_trace(
    svn_wc__internal_ensure_adm(wc_ctx->db, local_abspath, url, repos_root_url,
                                repos_uuid, revision, depth, scratch_pool));
}

svn_error_t *
svn_wc__adm_destroy(svn_wc__db_t *db,
                    const char *dir_abspath,
                    svn_cancel_func_t cancel_func,
                    void *cancel_baton,
                    apr_pool_t *scratch_pool)
{
  svn_boolean_t is_wcroot;

  SVN_ERR_ASSERT(svn_dirent_is_absolute(dir_abspath));

  SVN_ERR(svn_wc__write_check(db, dir_abspath, scratch_pool));

  SVN_ERR(svn_wc__db_is_wcroot(&is_wcroot, db, dir_abspath, scratch_pool));

  /* Well, the coast is clear for blowing away the administrative
     directory, which also removes remaining locks */

  /* Now close the DB, and we can delete the working copy */
  if (is_wcroot)
    {
      SVN_ERR(svn_wc__db_drop_root(db, dir_abspath, scratch_pool));
      SVN_ERR(svn_io_remove_dir2(svn_wc__adm_child(dir_abspath, NULL,
                                                   scratch_pool),
                                 FALSE,
                                 cancel_func, cancel_baton,
                                 scratch_pool));
    }

  return SVN_NO_ERROR;
}


svn_error_t *
svn_wc__adm_cleanup_tmp_area(svn_wc__db_t *db,
                             const char *adm_abspath,
                             apr_pool_t *scratch_pool)
{
  const char *tmp_path;

  SVN_ERR_ASSERT(svn_dirent_is_absolute(adm_abspath));

  SVN_ERR(svn_wc__write_check(db, adm_abspath, scratch_pool));

  /* Get the path to the tmp area, and blow it away. */
  tmp_path = svn_wc__adm_child(adm_abspath, SVN_WC__ADM_TMP, scratch_pool);

  SVN_ERR(svn_io_remove_dir2(tmp_path, TRUE, NULL, NULL, scratch_pool));

  /* Now, rebuild the tmp area. */
  return svn_error_trace(init_adm_tmp_area(adm_abspath, scratch_pool));
}


svn_error_t *
svn_wc__get_tmpdir(const char **tmpdir_abspath,
                   svn_wc_context_t *wc_ctx,
                   const char *wri_abspath,
                   apr_pool_t *result_pool,
                   apr_pool_t *scratch_pool)
{
  SVN_ERR(svn_wc__db_temp_wcroot_tempdir(tmpdir_abspath,
                                         wc_ctx->db, wri_abspath,
                                         result_pool, scratch_pool));
  return SVN_NO_ERROR;
}