/*
 * getdate.c :  entry point for get_dated_revision for ra_serf
 *
 * ====================================================================
 * Copyright (c) 2006-2007 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 <apr_uri.h>

#include <expat.h>

#include <serf.h>

#include "svn_pools.h"
#include "svn_ra.h"
#include "svn_dav.h"
#include "svn_xml.h"
#include "../libsvn_ra/ra_loader.h"
#include "svn_config.h"
#include "svn_delta.h"
#include "svn_version.h"
#include "svn_path.h"
#include "svn_time.h"

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

#include "ra_serf.h"


/*
 * This enum represents the current state of our XML parsing for a REPORT.
 */
typedef enum {
  NONE = 0,
  VERSION_NAME,
} date_state_e;

typedef struct {
  /* The currently collected value as we build it up */
  const char *tmp;
  apr_size_t tmp_len;
} date_info_t;

typedef struct {
  apr_pool_t *pool;

  /* The time asked about. */
  apr_time_t time;

  /* What was the youngest revision at that time? */
  svn_revnum_t *revision;

  /* are we done? */
  svn_boolean_t done;

} date_context_t;


static date_info_t *
push_state(svn_ra_serf__xml_parser_t *parser,
           date_context_t *date_ctx,
           date_state_e state)
{
  svn_ra_serf__xml_push_state(parser, state);

  if (state == VERSION_NAME)
    {
      date_info_t *info;

      info = apr_pcalloc(parser->state->pool, sizeof(*info));

      parser->state->private = info;
    }

  return parser->state->private;
}

static svn_error_t *
start_getdate(svn_ra_serf__xml_parser_t *parser,
              void *userData,
              svn_ra_serf__dav_props_t name,
              const char **attrs)
{
  date_context_t *date_ctx = userData;
  date_state_e state;

  state = parser->state->current_state;

  if (state == NONE &&
      strcmp(name.name, SVN_DAV__VERSION_NAME) == 0)
    {
      push_state(parser, date_ctx, VERSION_NAME);
    }

  return SVN_NO_ERROR;
}

static svn_error_t *
end_getdate(svn_ra_serf__xml_parser_t *parser,
            void *userData,
            svn_ra_serf__dav_props_t name)
{
  date_context_t *date_ctx = userData;
  date_state_e state;
  date_info_t *info;

  state = parser->state->current_state;
  info = parser->state->private;

  if (state == VERSION_NAME &&
      strcmp(name.name, SVN_DAV__VERSION_NAME) == 0)
    {
      *date_ctx->revision = SVN_STR_TO_REV(info->tmp);
      svn_ra_serf__xml_pop_state(parser);
    }

  return SVN_NO_ERROR;
}

static svn_error_t *
cdata_getdate(svn_ra_serf__xml_parser_t *parser,
              void *userData,
              const char *data,
              apr_size_t len)
{
  date_context_t *date_ctx = userData;
  date_state_e state;
  date_info_t *info;

  UNUSED_CTX(date_ctx);

  state = parser->state->current_state;
  info = parser->state->private;

  switch (state)
    {
    case VERSION_NAME:
        svn_ra_serf__expand_string(&info->tmp, &info->tmp_len,
                                   data, len, parser->state->pool);
        break;
    default:
        break;
    }

  return SVN_NO_ERROR;
}

#define GETDATE_HEADER "<S:dated-rev-report xmlns:S=\"" SVN_XML_NAMESPACE "\" xmlns:D=\"DAV:\">"
#define GETDATE_FOOTER "</S:dated-rev-report>"

static serf_bucket_t*
create_getdate_body(void *baton,
                    serf_bucket_alloc_t *alloc,
                    apr_pool_t *pool)
{
  serf_bucket_t *buckets, *tmp;
  date_context_t *date_ctx = baton;

  buckets = serf_bucket_aggregate_create(alloc);

  tmp = SERF_BUCKET_SIMPLE_STRING_LEN(GETDATE_HEADER,
                                      sizeof(GETDATE_HEADER) - 1,
                                      alloc);
  serf_bucket_aggregate_append(buckets, tmp);

  svn_ra_serf__add_tag_buckets(buckets,
                               "D:" SVN_DAV__CREATIONDATE,
                               svn_time_to_cstring(date_ctx->time, pool),
                               alloc);

  tmp = SERF_BUCKET_SIMPLE_STRING_LEN(GETDATE_FOOTER,
                                      sizeof(GETDATE_FOOTER)-1,
                                      alloc);
  serf_bucket_aggregate_append(buckets, tmp);

  return buckets;
}

svn_error_t *
svn_ra_serf__get_dated_revision(svn_ra_session_t *ra_session,
                                svn_revnum_t *revision,
                                apr_time_t tm,
                                apr_pool_t *pool)
{
  date_context_t *date_ctx;
  svn_ra_serf__session_t *session = ra_session->priv;
  svn_ra_serf__handler_t *handler;
  svn_ra_serf__xml_parser_t *parser_ctx;
  const char *vcc_url;
  int status_code;

  date_ctx = apr_pcalloc(pool, sizeof(*date_ctx));
  date_ctx->pool = pool;
  date_ctx->time = tm;
  date_ctx->revision = revision;
  date_ctx->done = FALSE;

  SVN_ERR(svn_ra_serf__discover_root(&vcc_url, NULL,
                                     session, session->conns[0],
                                     session->repos_url.path, pool));

  handler = apr_pcalloc(pool, sizeof(*handler));

  handler->method = "REPORT";
  handler->path = vcc_url;
  handler->body_type = "text/xml";
  handler->conn = session->conns[0];
  handler->session = session;

  parser_ctx = apr_pcalloc(pool, sizeof(*parser_ctx));

  parser_ctx->pool = pool;
  parser_ctx->user_data = date_ctx;
  parser_ctx->start = start_getdate;
  parser_ctx->end = end_getdate;
  parser_ctx->cdata = cdata_getdate;
  parser_ctx->done = &date_ctx->done;
  parser_ctx->status_code = &status_code;

  handler->body_delegate = create_getdate_body;
  handler->body_delegate_baton = date_ctx;

  handler->response_handler = svn_ra_serf__handle_xml_parser;
  handler->response_baton = parser_ctx;

  svn_ra_serf__request_create(handler);

  *date_ctx->revision = SVN_INVALID_REVNUM;

  SVN_ERR(svn_ra_serf__context_run_wait(&date_ctx->done, session, pool));

  return SVN_NO_ERROR;
}
