#ifdef FOSSIL_ENABLE_JSON
/*
** Copyright (c) 2011 D. Richard Hipp
**
** This program is free software; you can redistribute it and/or
** modify it under the terms of the Simplified BSD License (also
** known as the "2-Clause License" or "FreeBSD License".)
**
** This program is distributed in the hope that it will be useful,
** but without any warranty; without even the implied warranty of
** merchantability or fitness for a particular purpose.
**
** Author contact information:
**   drh@hwaci.com
**   http://www.hwaci.com/drh/
**
*/
#include "VERSION.h"
#include "config.h"
#include "json_wiki.h"

#if INTERFACE
#include "json_detail.h"
#endif

static cson_value * json_wiki_create();
static cson_value * json_wiki_get();
static cson_value * json_wiki_list();
static cson_value * json_wiki_save();

/*
** Mapping of /json/wiki/XXX commands/paths to callbacks.
*/
static const JsonPageDef JsonPageDefs_Wiki[] = {
{"create", json_wiki_create, 1},
{"get", json_wiki_get, 0},
{"list", json_wiki_list, 0},
{"save", json_wiki_save, 1},
{"timeline", json_timeline_wiki,0},
/* Last entry MUST have a NULL name. */
{NULL,NULL,0}
};


/*
** Implements the /json/wiki family of pages/commands.
**
*/
cson_value * json_page_wiki(){
  return json_page_dispatch_helper(&JsonPageDefs_Wiki[0]);
}


/*
** Loads the given wiki page and creates a JSON object representation
** of it. If the page is not found then NULL is returned. If
** contentFormat is positive true then the page content is HTML-ized
** using fossil's conventional wiki format, if it is negative then no
** parsing is performed, if it is 0 then the content is not returned
** in the response. If contentFormat is 0 then the contentSize reflects
** the number of bytes, not characters, stored in the page.
**
** The returned value, if not NULL, is-a JSON Object owned by the
** caller. If it returns NULL then it may set g.json's error state.
*/
cson_value * json_get_wiki_page_by_name(char const * zPageName, char contentFormat){
  int rid;
  Manifest *pWiki = 0;
  char * zUuid = NULL;
  Stmt q;
  db_prepare(&q,
             "SELECT x.rid, b.uuid FROM tag t, tagxref x, blob b"
             " WHERE x.tagid=t.tagid AND t.tagname='wiki-%q' "
             " AND b.rid=x.rid"
             " ORDER BY x.mtime DESC LIMIT 1",
             zPageName 
             );
  if( (SQLITE_ROW != db_step(&q)) ){
    db_finalize(&q);
    json_set_err( FSL_JSON_E_RESOURCE_NOT_FOUND, "Wiki page not found: %s",
                  zPageName );
    return NULL;
  }
  rid = db_column_int(&q,0);
  zUuid = db_column_malloc(&q,1);
  db_finalize(&q);
  if( NULL == (pWiki = manifest_get(rid, CFTYPE_WIKI)) ){
    free(zUuid);
    json_set_err( FSL_JSON_E_UNKNOWN,
                  "Error reading wiki page from manifest (rid=%d, uuid=%s).",
                  rid, zUuid );
    return NULL;
  }else{
    char const * zFormat = NULL;
    unsigned int len = 0;
    cson_object * pay = cson_new_object();
    char const * zBody = pWiki->zWiki;
    cson_object_set(pay,"name",json_new_string(zPageName));
    cson_object_set(pay,"uuid",json_new_string(zUuid));
    free(zUuid);
    zUuid = NULL;
    /*cson_object_set(pay,"rid",json_new_int((cson_int_t)rid));*/
    cson_object_set(pay,"lastSavedBy",json_new_string(pWiki->zUser));
    cson_object_set(pay,FossilJsonKeys.timestamp,
                    json_julian_to_timestamp(pWiki->rDate));
    

    if(0 == contentFormat){
      cson_object_set(pay,"contentLength",
                      json_new_int((cson_int_t)(zBody?strlen(zBody):0)));
    }else{
      cson_object_set(pay,"contentFormat",json_new_string(zFormat));
      if( contentFormat>0 ){/*HTML-ize it*/
        Blob content = empty_blob;
        Blob raw = empty_blob;
        if(zBody && *zBody){
          blob_append(&raw,zBody,-1);
          wiki_convert(&raw,&content,0);
          len = (unsigned int)blob_size(&content);
        }
        cson_object_set(pay,"contentLength",json_new_int((cson_int_t)len));
        cson_object_set(pay,"content",
                        cson_value_new_string(blob_buffer(&content),len));
        blob_reset(&content);
        blob_reset(&raw);
      }else{/*raw format*/
        len = zBody ? strlen(zBody) : 0;
        cson_object_set(pay,"contentLength",json_new_int((cson_int_t)len));
        cson_object_set(pay,"content",cson_value_new_string(zBody,len));
      }
    }
    /*TODO: add 'T' (tag) fields*/
    /*TODO: add the 'A' card (file attachment) entries?*/
    manifest_destroy(pWiki);
    return cson_object_value(pay);
  }  
  
}


/*
** Searches for a wiki page with the given rid. If found it behaves
** like json_get_wiki_page_by_name(pageName, contentFormat), else it returns
** NULL.
*/
cson_value * json_get_wiki_page_by_rid(int rid, char contentFormat){
  char * zPageName = NULL;
  cson_value * rc = NULL;
  zPageName = db_text(NULL,
                      "SELECT substr(t.tagname,6) AS name "
                      " FROM tag t, tagxref x, blob b "
                      " WHERE b.rid=%d "
                      " AND t.tagname GLOB 'wiki-*'"
                      " AND x.tagid=t.tagid AND b.rid=x.rid ",
                      rid);
  if( zPageName ){
    rc = json_get_wiki_page_by_name(zPageName, contentFormat);
    free(zPageName);
  }
  return rc;
}

/*
** Implementation of /json/wiki/get.
**
*/
static cson_value * json_wiki_get(){
  int rid;
  Manifest *pWiki = 0;
  char const * zBody = NULL;
  char const * zPageName;
  char const * zFormat = NULL;
  char * zUuid = NULL;
  char contentFormat = -1;
  Stmt q;
  if( !g.perm.RdWiki && !g.perm.Read ){
    json_set_err(FSL_JSON_E_DENIED,
                 "Requires 'o' or 'j' access.");
    return NULL;
  }
  zPageName = json_find_option_cstr("name",NULL,"n")
      /* Damn... fossil automatically sets name to the PATH
         part after /json, so we need a workaround down here....
      */
      ;
  if( zPageName && (NULL != strstr(zPageName, "/"))){
      /* Assume that we picked up a path remnant. */
      zPageName = NULL;
  }
  if( !zPageName && cson_value_is_string(g.json.reqPayload.v) ){
      zPageName = cson_string_cstr(cson_value_get_string(g.json.reqPayload.v));
  }
  if(!zPageName){
    zPageName = json_command_arg(g.json.dispatchDepth+1);
  }
  if(!zPageName||!*zPageName){
    json_set_err(FSL_JSON_E_MISSING_ARGS,
                 "'name' argument is missing.");
    return NULL;
  }

  zFormat = json_find_option_cstr("format",NULL,"f");
  if(!zFormat || !*zFormat || ('r'==*zFormat)){
    contentFormat = -1;
  }
  else if('h'==*zFormat){
    contentFormat = 1;
  }
  else if('n'==*zFormat){
    contentFormat = 0;
  }
  return json_get_wiki_page_by_name(zPageName, contentFormat);
}

/*
** Internal impl of /wiki/save and /wiki/create. If createMode is 0
** and the page already exists then a
** FSL_JSON_E_RESOURCE_ALREADY_EXISTS error is triggered.  If
** createMode is false then the FSL_JSON_E_RESOURCE_NOT_FOUND is
** triggered if the page does not already exists.
**
** Note that the error triggered when createMode==0 and no such page
** exists is rather arbitrary - we could just as well create the entry
** here if it doesn't already exist. With that, save/create would
** become one operation. That said, i expect there are people who
** would categorize such behaviour as "being too clever" or "doing too
** much automatically" (and i would likely agree with them).
**
** If allowCreateIfExists is true then this function will allow a new
** page to be created even if createMode is false.
*/
static cson_value * json_wiki_create_or_save(char createMode,
                                             char allowCreateIfExists){
  Blob content = empty_blob;  /* wiki  page content */
  cson_value * nameV;         /* wiki page name */
  char const * zPageName;     /* cstr form of page name */
  cson_value * contentV;      /* passed-in content */
  cson_value * emptyContent = NULL;  /* placeholder for empty content. */
  cson_value * payV = NULL;   /* payload/return value */
  cson_string const * jstr = NULL;  /* temp for cson_value-to-cson_string conversions. */
  unsigned int contentLen = 0;
  int rid;
  if( (createMode && !g.perm.NewWiki)
      || (!createMode && !g.perm.WrWiki)){
    json_set_err(FSL_JSON_E_DENIED,
                 "Requires '%c' permissions.",
                 (createMode ? 'f' : 'k'));
    return NULL;
  }
  nameV = json_req_payload_get("name");
  if(!nameV){
    json_set_err( FSL_JSON_E_MISSING_ARGS,
                  "'name' parameter is missing.");
    return NULL;
  }
  zPageName = cson_string_cstr(cson_value_get_string(nameV));
  rid = db_int(0,
     "SELECT x.rid FROM tag t, tagxref x"
     " WHERE x.tagid=t.tagid AND t.tagname='wiki-%q'"
     " ORDER BY x.mtime DESC LIMIT 1",
     zPageName
  );

  if(rid){
    if(createMode){
      json_set_err(FSL_JSON_E_RESOURCE_ALREADY_EXISTS,
                   "Wiki page '%s' already exists.",
                   zPageName);
      goto error;
    }
  }else if(!allowCreateIfExists){
    json_set_err(FSL_JSON_E_RESOURCE_NOT_FOUND,
                 "Wiki page '%s' not found.",
                 zPageName);
    goto error;
  }

  contentV = json_req_payload_get("content");
  if( !contentV ){
    if( createMode || (!rid && allowCreateIfExists) ){
      contentV = emptyContent = cson_value_new_string("",0);
    }else{
      json_set_err(FSL_JSON_E_MISSING_ARGS,
                   "'content' parameter is missing.");
      goto error;
    }
  }
  if( !cson_value_is_string(nameV)
      || !cson_value_is_string(contentV)){
    json_set_err(FSL_JSON_E_INVALID_ARGS,
                 "'name' and 'content' parameters must be strings.");
    goto error;
  }
  jstr = cson_value_get_string(contentV);
  contentLen = (int)cson_string_length_bytes(jstr);
  if(contentLen){
    blob_append(&content, cson_string_cstr(jstr),contentLen);
  }
  wiki_cmd_commit(zPageName, 0==rid, &content);
  blob_reset(&content);
  /*
    Our return value here has a race condition: if this operation
    is called concurrently for the same wiki page via two requests,
    payV could reflect the results of the other save operation.
  */
  payV = json_get_wiki_page_by_name(
           cson_string_cstr(
             cson_value_get_string(nameV)),
             0);
  goto ok;
  error:
  assert( 0 != g.json.resultCode );
  assert( NULL == payV );
  ok:
  if( emptyContent ){
    /* We have some potentially tricky memory ownership
       here, which is why we handle emptyContent separately.

       This is, in fact, overkill because cson_value_new_string("",0)
       actually returns a shared singleton instance (i.e. doesn't
       allocate), but that is a cson implementation detail which i
       don't want leaking into this code...
    */
    cson_value_free(emptyContent);
  }
  return payV;

}

/*
** Implementation of /json/wiki/create.
*/
static cson_value * json_wiki_create(){
  return json_wiki_create_or_save(1,0);
}

/*
** Implementation of /json/wiki/save.
*/
static cson_value * json_wiki_save(){
  char const createIfNotExists = json_getenv_bool("createIfNotExists",0);
  return json_wiki_create_or_save(0,createIfNotExists);
}

/*
** Implementation of /json/wiki/list.
*/
static cson_value * json_wiki_list(){
  cson_value * listV = NULL;
  cson_array * list = NULL;
  Stmt q;
  char const verbose = json_find_option_bool("verbose",NULL,"v",0);

  if( !g.perm.RdWiki && !g.perm.Read ){
    json_set_err(FSL_JSON_E_DENIED,
                 "Requires 'j' or 'o' permissions.");
    return NULL;
  }
  db_prepare(&q,"SELECT"
             " substr(tagname,6) as name"
             " FROM tag WHERE tagname GLOB 'wiki-*'"
             " ORDER BY lower(name)");
  listV = cson_value_new_array();
  list = cson_value_get_array(listV);
  while( SQLITE_ROW == db_step(&q) ){
    cson_value * v;
    if( verbose ){
      char const * name = db_column_text(&q,0);
      v = json_get_wiki_page_by_name(name,0);
    }else{
      v = cson_sqlite3_column_to_value(q.pStmt,0);
    }
    if(!v){
      json_set_err(FSL_JSON_E_UNKNOWN,
                   "Could not convert wiki name column to JSON.");
      goto error;
    }else if( 0 != cson_array_append( list, v ) ){
      cson_value_free(v);
      json_set_err(FSL_JSON_E_ALLOC,"Could not append wiki page name to array.")
        /* OOM (or maybe numeric overflow) are the only realistic
           error codes for that particular failure.*/;
      goto error;
    }
  }
  goto end;
  error:
  assert(0 != g.json.resultCode);
  cson_value_free(listV);
  listV = NULL;
  end:
  db_finalize(&q);
  return listV;
}
#endif /* FOSSIL_ENABLE_JSON */