/*
 * info.c:  return system-generated metadata about paths or URLs.
 *
 * ====================================================================
 * Copyright (c) 2000-2007 CollabNet.  All rights reserved.
 *
 * This software is licensed as described in the file COPYING, which
 * you should have received as part of this distribution.  The terms
 * are also available at http://subversion.tigris.org/license-1.html.
 * If newer versions of this license are posted there, you may use a
 * newer version instead, at your option.
 *
 * This software consists of voluntary contributions made by many
 * individuals.  For exact contribution history, see the revision
 * history and logs, available at http://subversion.tigris.org/.
 * ====================================================================
 */

/* ==================================================================== */



#include "client.h"
#include "svn_client.h"
#include "svn_pools.h"
#include "svn_path.h"
#include "svn_hash.h"
#include "svn_wc.h"

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


/* Helper: build an svn_info_t *INFO struct from svn_dirent_t DIRENT
   and (possibly NULL) svn_lock_t LOCK, all allocated in POOL.
   Pointer fields are copied by reference, not dup'd. */
static svn_error_t *
build_info_from_dirent(svn_info_t **info,
                       const svn_dirent_t *dirent,
                       svn_lock_t *lock,
                       const char *URL,
                       svn_revnum_t revision,
                       const char *repos_UUID,
                       const char *repos_root,
                       apr_pool_t *pool)
{
  svn_info_t *tmpinfo = apr_pcalloc(pool, sizeof(*tmpinfo));

  tmpinfo->URL                  = URL;
  tmpinfo->rev                  = revision;
  tmpinfo->kind                 = dirent->kind;
  tmpinfo->repos_UUID           = repos_UUID;
  tmpinfo->repos_root_URL       = repos_root;
  tmpinfo->last_changed_rev     = dirent->created_rev;
  tmpinfo->last_changed_date    = dirent->time;
  tmpinfo->last_changed_author  = dirent->last_author;
  tmpinfo->lock                 = lock;
  tmpinfo->depth                = svn_depth_unknown;
  tmpinfo->working_size         = SVN_INFO_SIZE_UNKNOWN;
  tmpinfo->size                 = dirent->size;

  *info = tmpinfo;
  return SVN_NO_ERROR;
}


/* Helper: build an svn_info_t *INFO struct from svn_wc_entry_t ENTRY,
   allocated in POOL.  Pointer fields are copied by reference, not dup'd. */
static svn_error_t *
build_info_from_entry(svn_info_t **info,
                      const svn_wc_entry_t *entry,
                      apr_pool_t *pool)
{
  svn_info_t *tmpinfo = apr_pcalloc(pool, sizeof(*tmpinfo));

  tmpinfo->URL                  = entry->url;
  tmpinfo->rev                  = entry->revision;
  tmpinfo->kind                 = entry->kind;
  tmpinfo->repos_UUID           = entry->uuid;
  tmpinfo->repos_root_URL       = entry->repos;
  tmpinfo->last_changed_rev     = entry->cmt_rev;
  tmpinfo->last_changed_date    = entry->cmt_date;
  tmpinfo->last_changed_author  = entry->cmt_author;

  /* entry-specific stuff */
  tmpinfo->has_wc_info          = TRUE;
  tmpinfo->schedule             = entry->schedule;
  tmpinfo->depth                = entry->depth;
  tmpinfo->copyfrom_url         = entry->copyfrom_url;
  tmpinfo->copyfrom_rev         = entry->copyfrom_rev;
  tmpinfo->text_time            = entry->text_time;
  tmpinfo->prop_time            = entry->prop_time;
  tmpinfo->checksum             = entry->checksum;
  tmpinfo->conflict_old         = entry->conflict_old;
  tmpinfo->conflict_new         = entry->conflict_new;
  tmpinfo->conflict_wrk         = entry->conflict_wrk;
  tmpinfo->prejfile             = entry->prejfile;
  tmpinfo->changelist           = entry->changelist;
  tmpinfo->working_size         = entry->working_size;
  tmpinfo->size                 = SVN_INFO_SIZE_UNKNOWN;

  /* lock stuff */
  if (entry->lock_token)  /* the token is the critical bit. */
    {
      tmpinfo->lock = apr_pcalloc(pool, sizeof(*(tmpinfo->lock)));

      tmpinfo->lock->token      = entry->lock_token;
      tmpinfo->lock->owner      = entry->lock_owner;
      tmpinfo->lock->comment    = entry->lock_comment;
      tmpinfo->lock->creation_date = entry->lock_creation_date;
    }

  *info = tmpinfo;
  return SVN_NO_ERROR;
}


/* The dirent fields we care about for our calls to svn_ra_get_dir2. */
#define DIRENT_FIELDS (SVN_DIRENT_KIND        | \
                       SVN_DIRENT_CREATED_REV | \
                       SVN_DIRENT_TIME        | \
                       SVN_DIRENT_LAST_AUTHOR)


/* Helper func for recursively fetching svn_dirent_t's from a remote
   directory and pushing them at an info-receiver callback.

   DEPTH is the depth starting at DIR, even though RECEIVER is never
   invoked on DIR: if DEPTH is svn_depth_immediates, then invoke
   RECEIVER on all children of DIR, but none of their children; if
   svn_depth_files, then invoke RECEIVER on file children of DIR but
   not on subdirectories; if svn_depth_infinity, recurse fully.
*/
static svn_error_t *
push_dir_info(svn_ra_session_t *ra_session,
              const char *session_URL,
              const char *dir,
              svn_revnum_t rev,
              const char *repos_UUID,
              const char *repos_root,
              svn_info_receiver_t receiver,
              void *receiver_baton,
              svn_depth_t depth,
              svn_client_ctx_t *ctx,
              apr_hash_t *locks,
              apr_pool_t *pool)
{
  apr_hash_t *tmpdirents;
  svn_dirent_t *the_ent;
  svn_info_t *info;
  apr_hash_index_t *hi;
  apr_pool_t *subpool = svn_pool_create(pool);

  SVN_ERR(svn_ra_get_dir2(ra_session, &tmpdirents, NULL, NULL,
                          dir, rev, DIRENT_FIELDS, pool));

  for (hi = apr_hash_first(pool, tmpdirents); hi; hi = apr_hash_next(hi))
    {
      const char *path, *URL, *fs_path;
      const void *key;
      svn_lock_t *lock;
      void *val;

      svn_pool_clear(subpool);

      if (ctx->cancel_func)
        SVN_ERR(ctx->cancel_func(ctx->cancel_baton));

      apr_hash_this(hi, &key, NULL, &val);
      the_ent = val;

      path = svn_path_join(dir, key, subpool);
      URL  = svn_path_url_add_component(session_URL, key, subpool);

      fs_path = svn_path_is_child(repos_root, URL, subpool);
      fs_path = apr_pstrcat(subpool, "/", fs_path, NULL);
      fs_path = svn_path_uri_decode(fs_path, subpool);

      lock = apr_hash_get(locks, fs_path, APR_HASH_KEY_STRING);

      SVN_ERR(build_info_from_dirent(&info, the_ent, lock, URL, rev,
                                     repos_UUID, repos_root, subpool));

      if (depth >= svn_depth_immediates
          || (depth == svn_depth_files && the_ent->kind == svn_node_file))
        {
          SVN_ERR(receiver(receiver_baton, path, info, subpool));
        }

      if (depth == svn_depth_infinity && the_ent->kind == svn_node_dir)
        {
          SVN_ERR(push_dir_info(ra_session, URL, path,
                                rev, repos_UUID, repos_root,
                                receiver, receiver_baton,
                                depth, ctx, locks, subpool));
        }
    }

  svn_pool_destroy(subpool);

  return SVN_NO_ERROR;
}



/* Callback and baton for crawl_entries() walk over entries files. */
struct found_entry_baton
{
  apr_hash_t *changelist_hash;
  svn_info_receiver_t receiver;
  void *receiver_baton;
};

static svn_error_t *
info_found_entry_callback(const char *path,
                          const svn_wc_entry_t *entry,
                          void *walk_baton,
                          apr_pool_t *pool)
{
  struct found_entry_baton *fe_baton = walk_baton;

  /* We're going to receive dirents twice;  we want to ignore the
     first one (where it's a child of a parent dir), and only print
     the second one (where we're looking at THIS_DIR.)  */
  if ((entry->kind == svn_node_dir)
      && (strcmp(entry->name, SVN_WC_ENTRY_THIS_DIR)))
    return SVN_NO_ERROR;

  if (SVN_WC__CL_MATCH(fe_baton->changelist_hash, entry))
    {
      svn_info_t *info;
      SVN_ERR(build_info_from_entry(&info, entry, pool));
      SVN_ERR(fe_baton->receiver(fe_baton->receiver_baton, path, info, pool));
    }
  return SVN_NO_ERROR;
}



static const svn_wc_entry_callbacks2_t
entry_walk_callbacks =
  {
    info_found_entry_callback,
    svn_client__default_walker_error_handler
  };


/* Helper function:  push the svn_wc_entry_t for WCPATH at
   RECEIVER/BATON, and possibly recurse over more entries. */
static svn_error_t *
crawl_entries(const char *wcpath,
              svn_info_receiver_t receiver,
              void *receiver_baton,
              svn_depth_t depth,
              apr_hash_t *changelist_hash,
              svn_client_ctx_t *ctx,
              apr_pool_t *pool)
{
  svn_wc_adm_access_t *adm_access;
  const svn_wc_entry_t *entry;
  int adm_lock_level = SVN_WC__LEVELS_TO_LOCK_FROM_DEPTH(depth);

  SVN_ERR(svn_wc_adm_probe_open3(&adm_access, NULL, wcpath, FALSE, 
                                 adm_lock_level, ctx->cancel_func, 
                                 ctx->cancel_baton, pool));
  SVN_ERR(svn_wc__entry_versioned(&entry, wcpath, adm_access, FALSE, pool));


  if (entry->kind == svn_node_file)
    {
      if (SVN_WC__CL_MATCH(changelist_hash, entry))
        {
          svn_info_t *info;
          SVN_ERR(build_info_from_entry(&info, entry, pool));
          return receiver(receiver_baton, wcpath, info, pool);
        }
    }
  else if (entry->kind == svn_node_dir)
    {
      struct found_entry_baton fe_baton;
      fe_baton.changelist_hash = changelist_hash;
      fe_baton.receiver = receiver;
      fe_baton.receiver_baton = receiver_baton;
      SVN_ERR(svn_wc_walk_entries3(wcpath, adm_access,
                                   &entry_walk_callbacks, &fe_baton,
                                   depth, FALSE, ctx->cancel_func,
                                   ctx->cancel_baton, pool));
    }

  return SVN_NO_ERROR;
}

/* Set *SAME_P to TRUE if URL exists in the head of the repository and
   refers to the same resource as it does in REV, using POOL for
   temporary allocations.  RA_SESSION is an open RA session for URL.  */
static svn_error_t *
same_resource_in_head(svn_boolean_t *same_p,
                      const char *url,
                      svn_revnum_t rev,
                      svn_ra_session_t *ra_session,
                      svn_client_ctx_t *ctx,
                      apr_pool_t *pool)
{
  svn_error_t *err;
  svn_opt_revision_t start_rev, end_rev, peg_rev;
  svn_opt_revision_t *ignored_rev;
  const char *head_url, *ignored_url;

  start_rev.kind = svn_opt_revision_head;
  peg_rev.kind = svn_opt_revision_number;
  peg_rev.value.number = rev;
  end_rev.kind = svn_opt_revision_unspecified;

  err = svn_client__repos_locations(&head_url, &ignored_rev,
                                    &ignored_url, &ignored_rev,
                                    ra_session,
                                    url, &peg_rev,
                                    &start_rev, &end_rev,
                                    ctx, pool);
  if (err &&
      ((err->apr_err == SVN_ERR_CLIENT_UNRELATED_RESOURCES) ||
       (err->apr_err == SVN_ERR_FS_NOT_FOUND)))
    {
      svn_error_clear(err);
      *same_p = FALSE;
    }
  else if (err)
    return err;
  else
    {
      /* ### Currently, the URLs should always be equal, since we can't
         ### walk forwards in history. */
      if (strcmp(url, head_url) == 0)
        *same_p = TRUE;
      else
        *same_p = FALSE;
    }

  return SVN_NO_ERROR;
}

svn_error_t *
svn_client_info2(const char *path_or_url,
                 const svn_opt_revision_t *peg_revision,
                 const svn_opt_revision_t *revision,
                 svn_info_receiver_t receiver,
                 void *receiver_baton,
                 svn_depth_t depth,
                 const apr_array_header_t *changelists,
                 svn_client_ctx_t *ctx,
                 apr_pool_t *pool)
{
  svn_ra_session_t *ra_session, *parent_ra_session;
  svn_revnum_t rev;
  const char *url;
  svn_node_kind_t url_kind;
  const char *repos_root_URL, *repos_UUID;
  svn_lock_t *lock;
  svn_boolean_t related;
  apr_hash_t *parent_ents;
  const char *parent_url, *base_name;
  svn_dirent_t *the_ent;
  svn_info_t *info;
  svn_error_t *err;

  if ((revision == NULL
       || revision->kind == svn_opt_revision_unspecified)
      && (peg_revision == NULL
          || peg_revision->kind == svn_opt_revision_unspecified))
    {
      /* Do all digging in the working copy. */
      apr_hash_t *changelist_hash = NULL;
      if (changelists && changelists->nelts)
        SVN_ERR(svn_hash_from_cstring_keys(&changelist_hash, 
                                           changelists, pool));
      return crawl_entries(path_or_url, receiver, receiver_baton,
                           depth, changelist_hash, ctx, pool);
    }

  /* Go repository digging instead. */

  /* Trace rename history (starting at path_or_url@peg_revision) and
     return RA session to the possibly-renamed URL as it exists in REVISION.
     The ra_session returned will be anchored on this "final" URL. */
  SVN_ERR(svn_client__ra_session_from_path(&ra_session, &rev,
                                           &url, path_or_url, NULL,
                                           peg_revision,
                                           revision, ctx, pool));

  SVN_ERR(svn_ra_get_repos_root2(ra_session, &repos_root_URL, pool));
  SVN_ERR(svn_ra_get_uuid2(ra_session, &repos_UUID, pool));

  svn_path_split(url, &parent_url, &base_name, pool);
  base_name = svn_path_uri_decode(base_name, pool);

  /* Get the dirent for the URL itself. */
  err = svn_ra_stat(ra_session, "", rev, &the_ent, pool);

  /* svn_ra_stat() will work against old versions of mod_dav_svn, but
     not old versions of svnserve.  In the case of a pre-1.2 svnserve,
     catch the specific error it throws:*/
  if (err && err->apr_err == SVN_ERR_RA_NOT_IMPLEMENTED)
    {
      /* Fall back to pre-1.2 strategy for fetching dirent's URL. */
      svn_error_clear(err);

      if (strcmp(url, repos_root_URL) == 0)
        {
          /* In this universe, there's simply no way to fetch
             information about the repository's root directory!
             If we're recursing, degrade gracefully: rather than
             throw an error, return no information about the
             repos root. */
          if (depth > svn_depth_empty)
            goto pre_1_2_recurse;

          /* Otherwise, we really are stuck.  Better tell the user
             what's going on. */
          return svn_error_createf(SVN_ERR_UNSUPPORTED_FEATURE, NULL,
                                   _("Server does not support retrieving "
                                     "information about the repository root"));
        }

      SVN_ERR(svn_ra_check_path(ra_session, "", rev, &url_kind, pool));
      if (url_kind == svn_node_none)
        return svn_error_createf(SVN_ERR_RA_ILLEGAL_URL, NULL,
                                 _("URL '%s' non-existent in revision %ld"),
                                 url, rev);

      /* Open a new RA session to the item's parent. */
      SVN_ERR(svn_client__open_ra_session_internal(&parent_ra_session,
                                                   parent_url, NULL,
                                                   NULL, NULL, FALSE, TRUE,
                                                   ctx, pool));

      /* Get all parent's entries, and find the item's dirent in the hash. */
      SVN_ERR(svn_ra_get_dir2(parent_ra_session, &parent_ents, NULL, NULL,
                              "", rev, DIRENT_FIELDS, pool));
      the_ent = apr_hash_get(parent_ents, base_name, APR_HASH_KEY_STRING);
      if (the_ent == NULL)
        return svn_error_createf(SVN_ERR_RA_ILLEGAL_URL, NULL,
                                 _("URL '%s' non-existent in revision %ld"),
                                 url, rev);
    }
  else if (err)
    {
      return err;
    }

  if (! the_ent)
    return svn_error_createf(SVN_ERR_RA_ILLEGAL_URL, NULL,
                             _("URL '%s' non-existent in revision %ld"),
                             url, rev);

  /* Check if the URL exists in HEAD and refers to the same resource.
     In this case, we check the repository for a lock on this URL.

     ### There is a possible race here, since HEAD might have changed since
     ### we checked it.  A solution to this problem could be to do the below
     ### check in a loop which only terminates if the HEAD revision is the same
     ### before and after this check.  That could, however, lead to a
     ### starvation situation instead.  */
  SVN_ERR(same_resource_in_head(&related, url, rev, ra_session, ctx, pool));
  if (related)
    {
      err = svn_ra_get_lock(ra_session, &lock, "", pool);

      /* An old mod_dav_svn will always work; there's nothing wrong with
         doing a PROPFIND for a property named "DAV:supportedlock". But
         an old svnserve will error. */
      if (err && err->apr_err == SVN_ERR_RA_NOT_IMPLEMENTED)
        {
          svn_error_clear(err);
          lock = NULL;
        }
      else if (err)
        return err;
    }
  else
    lock = NULL;

  /* Push the URL's dirent (and lock) at the callback.*/
  SVN_ERR(build_info_from_dirent(&info, the_ent, lock, url, rev,
                                 repos_UUID, repos_root_URL, pool));
  SVN_ERR(receiver(receiver_baton, base_name, info, pool));

  /* Possibly recurse, using the original RA session. */
  if (depth > svn_depth_empty && (the_ent->kind == svn_node_dir))
    {
      apr_hash_t *locks;

pre_1_2_recurse:
      if (peg_revision->kind == svn_opt_revision_head)
        {
          err = svn_ra_get_locks(ra_session, &locks, "", pool);

          /* Catch specific errors thrown by old mod_dav_svn or svnserve. */
          if (err &&
              (err->apr_err == SVN_ERR_RA_NOT_IMPLEMENTED
               || err->apr_err == SVN_ERR_UNSUPPORTED_FEATURE))
            {
              svn_error_clear(err);
              locks = apr_hash_make(pool); /* use an empty hash */
            }
          else if (err)
            return err;
        }
      else
        locks = apr_hash_make(pool); /* use an empty hash */

      SVN_ERR(push_dir_info(ra_session, url, "", rev,
                            repos_UUID, repos_root_URL,
                            receiver, receiver_baton,
                            depth, ctx, locks, pool));
    }

  return SVN_NO_ERROR;
}


svn_error_t *
svn_client_info(const char *path_or_url,
                const svn_opt_revision_t *peg_revision,
                const svn_opt_revision_t *revision,
                svn_info_receiver_t receiver,
                void *receiver_baton,
                svn_boolean_t recurse,
                svn_client_ctx_t *ctx,
                apr_pool_t *pool)
{
  return svn_client_info2(path_or_url, peg_revision, revision,
                          receiver, receiver_baton,
                          SVN_DEPTH_INFINITY_OR_EMPTY(recurse), 
                          NULL, ctx, pool);
}

svn_info_t *
svn_info_dup(const svn_info_t *info, apr_pool_t *pool)
{
  svn_info_t *dupinfo = apr_palloc(pool, sizeof(*dupinfo));

  /* Perform a trivial copy ... */
  *dupinfo = *info;

  /* ...and then re-copy stuff that needs to be duped into our pool. */
  if (info->URL)
    dupinfo->URL = apr_pstrdup(pool, info->URL);
  if (info->repos_root_URL)
    dupinfo->repos_root_URL = apr_pstrdup(pool, info->repos_root_URL);
  if (info->repos_UUID)
    dupinfo->repos_UUID = apr_pstrdup(pool, info->repos_UUID);
  if (info->last_changed_author)
    dupinfo->last_changed_author = apr_pstrdup(pool,
                                               info->last_changed_author);
  if (info->lock)
    dupinfo->lock = svn_lock_dup(info->lock, pool);
  if (info->copyfrom_url)
    dupinfo->copyfrom_url = apr_pstrdup(pool, info->copyfrom_url);
  if (info->checksum)
    dupinfo->checksum = apr_pstrdup(pool, info->checksum);
  if (info->conflict_old)
    dupinfo->conflict_old = apr_pstrdup(pool, info->conflict_old);
  if (info->conflict_new)
    dupinfo->conflict_new = apr_pstrdup(pool, info->conflict_new);
  if (info->conflict_wrk)
    dupinfo->conflict_wrk = apr_pstrdup(pool, info->conflict_wrk);
  if (info->prejfile)
    dupinfo->prejfile = apr_pstrdup(pool, info->prejfile);

  return dupinfo;
}
