#include "oaiconfig.h"

#include <algorithm>
#include <iostream>

#include "fileutil.h"

/**
 *  The mapping works as follows in the collect.cfg file.
 *
 *  A line is in the format oaimapping <collection field> <oai field>
 *
 *  The map here is used to look up the "Greenstone" name which is mapped from
 *  a given OAI field name, the reverse direction to that given in the 
 *  Greenstone collect.cfg file.  The oairecordaction class instance which
 *  produces output for an OAI record information request thus uses the map
 *  to work from the field in the collection it has on hand which OAI
 *  record name it should use instead.
 *
 *  An extension is to be used for this in which the OAI field name in the
 *  collect.cfg file can be made specific for a particular record format.
 *  This is done using the OAI field name in the format of 
 *    <OAI format>:<OAI field name>
 *  Thus, an rfc1807 Title field would be referred to as rfc1807:Title
 *
 *  A collection-level mapping is not needed - to configure the behaviour
 *  of a collection, ensure that you place the appropriate configuration in
 *  its etc/collect.cfg file - the oaimapping stuff IS NOT picked up from 
 *  the central main.cfg file at the moment.
 *
 *  In the absence of a particular format name, the mapping is taken to be
 *  universal.
 */

oaiconfig::oaiconfig() : configurable () {
  this->resumptionSize = -1; // Default = do not use resumption tokens
}

oaiconfig::oaiconfig(text_t &gsdlhome, text_t &gsdlcollect) 
{
  // read main configuration file to get oai collections
  text_t mainconfig = filename_cat(gsdlhome, "etc", "oai.cfg");
  this->collection = "";
  this->resumptionSize = -1;
  this->read_configfile(mainconfig);

  // then if we've not got a specified collection in the gsdlcollect
  // parameter, read in all the collection's individual configurations
  if (gsdlcollect == "") {
    text_tarray::iterator here = this->collectList.begin();
    text_tarray::iterator end  = this->collectList.end();
    while (here != end) {		
      this->configureCollection(gsdlhome, *here);
      ++here;
    }
  }
  else {
    this->configureCollection(gsdlhome, gsdlcollect);
  }
}

oaiconfig::~oaiconfig() 
{
  oaicollectmap::iterator here = this->collectMap.begin();
  oaicollectmap::iterator end  = this->collectMap.end();
  while (here != end) {
    delete here->second;
    ++here;
  }	
}

int oaiconfig::resumeAfter()
{ return this->resumptionSize;
}

int oaiconfig::getOAIVersion()
{ 
  if (this->oaiVersion == "1.1") {
    return 110;
  }
  return 200; 
}

void oaiconfig::configureCollection(const text_t &gsdlhome, const text_t &gsdlcollect)
{
  text_t cnfgfile = filename_cat(gsdlhome, "collect", gsdlcollect, "etc", "collect.cfg");
  this->collection = gsdlcollect;
  this->read_configfile(cnfgfile);
}

void oaiconfig::configure (const text_t &key, const text_tarray &cfgline)
{
  // we've got an oai mapping item, and at least two fields
  if (key == "oaimapping" && cfgline.size() > 1) {
    text_t::const_iterator colonAt;
    text_t index, name, configCollection;

    // Take a default collection as being whatever the collection being configured is...
    configCollection = this->collection;
    
    // get the name of the (collection) field to map; this may actually
    // be in a colon separated format of the type 
    // <collection name>:<field name>
    index = cfgline[0];
    if ((colonAt = find(index.begin(), index.end(), ':')) != index.end()) {
      configCollection = substr(index.begin(), colonAt);

      if (this->collection != "" && configCollection != this->collection) {
	cerr << "Attempt to configure OAI mappings for " << configCollection << " in " << this->collection << endl;
      }

      colonAt += 1;
      index = substr(colonAt, index.end());
    }
    
    // the second parameter is the metadata field to map the collection
    // field onto.  It may be provided with a metadata protocol (which
    // will be given first and separated by a period or full stop).  In 
    // the case of format.field name, the splitting is done here.
    if ((colonAt = find(cfgline[1].begin(), cfgline[1].end(), '.')) != cfgline[1].end()) {
      text_t stub = substr(cfgline[1].begin(), colonAt);
      colonAt += 1;
      name = substr(colonAt, cfgline[1].end());
      index.append(":");
      index.append(stub);
    }
    else {
      name = cfgline[1];
    }
    
    // now 'index' is in the form <collectionfield>:(formatname) 
    //     'name' is simply the fieldname within the format
    //     'configCollection' is the collection to be configured
    
    // now simply map the field name (index) onto the collection name (name)
    if (this->collectMap[configCollection] == NULL) {
      this->collectMap[configCollection] = new oaicollectconfig(configCollection);
    }
    this->collectMap[configCollection]->fieldMap[index] = name;
    
    //    cerr << "Mapping " << index << " to " << name << " in " << configCollection << endl;
    
    // TODO: check that the mapped field is actually in use
  }
  else if (key == "oaicollection" && cfgline.size() >= 1) {
    // Configure a collection to be used as part of the OAI archive.
    // This line should read:
    //
    // oaicollection <collectionname>
    //
    // Where <collectionname> is the name of the directory inside the
    // gsdl/collect folder which contains the collection.
    //
    // To configure several collections, merely repeat this line,
    // or alternatively use additional collection names after the
    // first one.
    //
    // This configuration should only appear in main.cfg
    //
    if (this->collection != "") {
      cerr << "Attempt to configure an oai collection outside of main.cfg" << endl;
      cerr << "Configuration attempted in " << this->collection << " collection." << endl;
      exit(1);
    }
    for (int c = 0; c < cfgline.size(); ++c) {
      this->collectList.push_back(cfgline[c]);
    }
  }
  else if (key == "oaiinfo" && cfgline.size() >= 1) {
    // Get a piece of information for the oai repository information
    // request.  The line should read:
    //
    // oaiinfo <information field name> <value>
    //
    // This configuration should only be attempted in main.cfg
    //
    if (this->collection != "") {
      cerr << "Attempt to set oai information outside of main.cfg" << endl;
      cerr << "Configuration attempted in " << this->collection << " collection." << endl;
      exit(1);
    }
    
    // if no second parameter is given, then the first parameter
    if (cfgline.size() == 1) {
      this->infoMap[cfgline[0]] = cfgline[0];
    }
    else {
      this->infoMap[cfgline[0]] = cfgline[1];
    }
  }
  else if (key == "oaiversion" && cfgline.size() >= 1) {
    this->oaiVersion = cfgline[0];
  }
  else if (key == "resumeafter" && cfgline.size() >= 1) {
    this->resumptionSize = cfgline[0].getint();
  }
  // get and note a maintainer item to support the Identify Verb of OAI
  else if (key == "maintainer" && cfgline.size() >= 1) {
    int line = 0;
    
    // TODO: exhaustive checks for empty or default values of maintainer
    while (line < cfgline.size()) {
      if (cfgline[line] != "NULL" &&
	  cfgline[line] != "") {
	// do something
	break;
      }
      else {
	++line;
      }
    }
    
    // Only try to set the configuration if we have a legitimate value ...
    if (line < cfgline.size()) {
      // ensure we have a map to write to
      if (this->collectMap[this->collection] == NULL) {
	this->collectMap[this->collection] = new oaicollectconfig(this->collection);
      }
      this->collectMap[this->collection]->maintainer = cfgline[line];
    }
  }
  else if (key == "repositoryName" && cfgline.size() >= 1) {
    int line = 0;
    
    // TODO: exhaustive checks for empty or default values of repositoryName
    while (line < cfgline.size()) {
      if (cfgline[line] != "NULL" &&
	  cfgline[line] != "") {
	// do something
	break;
      }
      else {
	++line;
      }
    }
    
    // Only try to set the configuration if we have a legitimate value ...
    if (line < cfgline.size()) {
      // ensure we have a map to write to
      if (this->collectMap[this->collection] == NULL) {
	this->collectMap[this->collection] = new oaicollectconfig(this->collection);
      }
      this->collectMap[this->collection]->repositoryName = cfgline[line];
    }
  }
  else if (key == "baseURL" && cfgline.size() >= 1) {
    int line = 0;
    
    while (line < cfgline.size()) {
      if (cfgline[line] != "NULL" &&
	  cfgline[line] != "") {
	// do something
	break;
      }
      else {
	++line;
      }
    }
    
    // Only try to set the configuration if we have a legitimate value ...
    if (line < cfgline.size()) {
      // ensure we have a map to write to
      if (this->collectMap[this->collection] == NULL) {
	this->collectMap[this->collection] = new oaicollectconfig(this->collection);
      }
      this->collectMap[this->collection]->baseURL = cfgline[line];
    }
  }
  else if (key == "baseDocRoot" && cfgline.size() >= 1) {
    int line = 0;
    
    while (line < cfgline.size()) {
      if (cfgline[line] != "NULL" &&
	  cfgline[line] != "") {
	// do something
	break;
      }
      else {
	++line;
      }
    }
    
    // Only try to set the configuration if we have a legitimate value ...
    if (line < cfgline.size()) {
      // ensure we have a map to write to
      if (this->collectMap[this->collection] == NULL) {
	this->collectMap[this->collection] = new oaicollectconfig(this->collection);
      }
      this->collectMap[this->collection]->baseDocRoot = cfgline[line];
    }
  }
}

/** 
 *  TODO: store all field values in a map per collection
 */
text_t oaiconfig::getCollectionConfig(const text_t &collection, const text_t &field)
{
  if (this->collectMap[collection] == NULL) {
    return "";
  }
  if (field == "maintainer") {
    return this->collectMap[collection]->maintainer;
  }

  if (field == "repositoryName") {
    return this->collectMap[collection]->repositoryName;
  }

  if (field == "baseURL") {
    return this->collectMap[collection]->baseURL;
  }

  if (field == "baseDocRoot") {
    return this->collectMap[collection]->baseDocRoot;
  }

  return "";
}

text_t oaiconfig::getMapping(const text_t &collection, const text_t &collectfield)
{
  if (this->collectMap[collection] == NULL) {
    return "";
  }
  return this->collectMap[collection]->fieldMap[collectfield];
}

/**
 *  Get the mapping for a field in a given collection; if no mapping
 *  exists, the result will be a blank string.
 */
text_t oaiconfig::getMapping(const text_t &collection, const text_t &collectfield, const text_t &formatname)
{
  text_t fullName = collectfield;
  fullName.append(":");
  fullName.append(formatname);

  // try the collection-specific options first
  if (this->collectMap[collection] != NULL) {
    // first try the most specific item - this collection, and given that protocol
    if (this->collectMap[collection]->fieldMap.count(fullName) >= 1) {
      return this->collectMap[collection]->fieldMap[fullName];
    }
    // otherwise, fall back to this collection, and all protocols
    else if (this->collectMap[collection]->fieldMap.count(collectfield) >= 1) {
      return this->collectMap[collection]->fieldMap[collectfield];
    }
  }

  // if no mappings exist, return an empty item
  if (this->collectMap[""] == NULL) {
    return "";
  }

  // then try generic rules
  if (this->collectMap[""]->fieldMap.count(fullName) >= 1) {
    return this->collectMap[""]->fieldMap[fullName];
  }
  else {
    return this->collectMap[""]->fieldMap[collectfield];
  }
}