package org.commcare.dalvik.provider;
import java.util.HashMap;
import java.util.Hashtable;
import java.util.NoSuchElementException;
import java.util.Vector;
import org.commcare.android.database.SqlStorage;
import org.commcare.android.database.user.models.ACase;
import org.commcare.android.util.SessionUnavailableException;
import org.commcare.cases.model.Case;
import org.commcare.dalvik.application.CommCareApplication;
import android.content.ContentProvider;
import android.content.ContentValues;
import android.database.Cursor;
import android.database.MatrixCursor;
import android.net.Uri;
/**
* The case data content provider defines the interface for external applications
* to gain read only access to the current user's sandbox. External applications require
* explicit permissions to access the content provider, and only data in the currently
* logged in user's sandbox is provided.
*
* The CaseDataAPI class is responsible for defining the data models and structures that
* can be queried with the content provider.
*
* Note that this content provider requires a permission to be granted for read access.
*
* No write access is currently supported.
*
* @author ctsims
*
*/
public class CaseDataContentProvider extends ContentProvider {
//Valid sql selectors
HashMap<String, String> caseMetaIndexTable = new HashMap<String, String>();
//TODO: Caching - Use a cache table here or use an LRU or other system provided cache?
/* (non-Javadoc)
* @see android.content.ContentProvider#getType(android.net.Uri)
*/
@Override
public String getType(Uri uri) {
int match = CaseDataAPI.UriMatch(uri);
switch(match) {
case CaseDataAPI.MetadataColumns.MATCH_CASES:
return CaseDataAPI.MetadataColumns.CONTENT_TYPE;
case CaseDataAPI.MetadataColumns.MATCH_CASE:
return CaseDataAPI.MetadataColumns.CONTENT_TYPE_ITEM;
case CaseDataAPI.DataColumns.MATCH_DATA:
return CaseDataAPI.DataColumns.CONTENT_TYPE;
case CaseDataAPI.IndexColumns.MATCH_INDEX:
return CaseDataAPI.IndexColumns.CONTENT_TYPE;
case CaseDataAPI.AttachmentColumns.MATCH_ATTACHMENTS:
return CaseDataAPI.AttachmentColumns.CONTENT_TYPE;
}
return null;
}
/* (non-Javadoc)
* @see android.content.ContentProvider#onCreate()
*/
@Override
public boolean onCreate() {
caseMetaIndexTable.put(CaseDataAPI.MetadataColumns.CASE_ID, Case.INDEX_CASE_ID);
caseMetaIndexTable.put(CaseDataAPI.MetadataColumns.CASE_TYPE, Case.INDEX_CASE_TYPE);
caseMetaIndexTable.put(CaseDataAPI.MetadataColumns.STATUS, Case.INDEX_CASE_STATUS);
return true;
}
/* (non-Javadoc)
* @see android.content.ContentProvider#query(android.net.Uri, java.lang.String[], java.lang.String, java.lang.String[], java.lang.String)
*/
@Override
public Cursor query(Uri uri, String[] projection, String selection, String[] selectionArgs, String sortOrder) {
//first, determine whether we're logged in and whether we have a valid data set to even be iterating over.
try {
CommCareApplication._().getUserDbHandle();
} catch(SessionUnavailableException sue) {
//This implies that the user isn't logged in. In the future we should probably broadcast an intent
//that notifies the other service to trigger a Login event.
return null;
}
//Standard dispatcher following Android best practices
int match = CaseDataAPI.UriMatch(uri);
switch(match) {
case CaseDataAPI.MetadataColumns.MATCH_CASES:
case CaseDataAPI.MetadataColumns.MATCH_CASE:
return queryCaseList(uri, projection, selection, selectionArgs, sortOrder);
case CaseDataAPI.DataColumns.MATCH_DATA:
return queryCaseData(uri.getLastPathSegment(), projection, selection, selectionArgs, sortOrder);
case CaseDataAPI.IndexColumns.MATCH_INDEX:
case CaseDataAPI.AttachmentColumns.MATCH_ATTACHMENTS:
//Unimplemented
return null;
}
throw new IllegalArgumentException("URI: " + uri.toString() +" is not a valid content path for CommCare Case Data");
}
//this is the complex case. Querying the full case database for metadata.
private Cursor queryCaseList(Uri uri, String[] projection, String selection, String[] selectionArgs, String sortOrder) {
//Not cached yet. Long term this should be a priority.
SqlStorage<ACase> storage = CommCareApplication._().getUserStorage(ACase.STORAGE_KEY, ACase.class);
//What we'd really like to do here is raw DB queries, but sadly it looks like we don't actually index
//enough of the right fields for that, so we're going to deserialize the models. We'll consider
//revising this API
MatrixCursor retCursor = new MatrixCursor(new String[] {CaseDataAPI.MetadataColumns._ID,
CaseDataAPI.MetadataColumns.CASE_ID,
CaseDataAPI.MetadataColumns.CASE_NAME,
CaseDataAPI.MetadataColumns.CASE_TYPE,
CaseDataAPI.MetadataColumns.DATE_OPENED,
CaseDataAPI.MetadataColumns.LAST_MODIFIED,
CaseDataAPI.MetadataColumns.OWNER_ID,
CaseDataAPI.MetadataColumns.STATUS});
//Allow for some selection processing, basically very simple AND filtering on indexes
Vector<String> keys = new Vector<String>();
Vector<String> values = new Vector<String>();
//If we don't have any selection args, skip all of this
if(selection != null) {
int currentArgVal = 0;
String[] selections = selection.toLowerCase().split("\\sand\\s");
for(String individualSelection : selections) {
String[] parts = individualSelection.split("=");
if(parts.length != 2) { throw new RuntimeException("Malformed content provider selection string component: " + individualSelection); }
String key = parts[0].trim();
if(!caseMetaIndexTable.containsKey(key)) {
throw new RuntimeException("Invalid selection key for case metadata: " + key);
}
String indexName = caseMetaIndexTable.get(key);
//remove any quotation marks and trim
String value = parts[1].replace("\"","").replace("'", "").trim();
//replace all "?"'s with arguments
while(value.indexOf("?") != -1) {
if(currentArgVal >= selectionArgs.length) { throw new RuntimeException("Selection string missing required arguments" + selection); }
value = value.substring(0, value.indexOf("?")) + selectionArgs[currentArgVal] + value.substring(value.indexOf("?") + 1);
currentArgVal++;
}
keys.add(indexName);
values.add(value);
}
//If we're matching a specific case (or trying to), add that as well)
if(CaseDataAPI.UriMatch(uri) != CaseDataAPI.MetadataColumns.MATCH_CASES) {
keys.add(ACase.INDEX_CASE_ID);
values.add(uri.getLastPathSegment());
}
//Do the db records fetch (one at a time, so as to not overload our working memory)
Vector<Integer> recordIds = storage.getIDsForValues((String[])keys.toArray(new String[0]), (String[])values.toArray(new String[0]));
for(int i : recordIds) {
Case c = storage.read(i);
retCursor.addRow(new Object[] {c.getID(), c.getCaseId(), c.getName(), c.getTypeId(), c.getDateOpened(), c.getLastModified(), c.getUserId(), c.isClosed() ? "closed" : "open"});
}
return retCursor;
}
//Otherwise we either need to iterate over all cases, or just get back the one (these are actually both generalizations of the above
//that should get centralized)
//No Case
if(CaseDataAPI.UriMatch(uri) == CaseDataAPI.MetadataColumns.MATCH_CASES) {
for(Case c: storage) {
retCursor.addRow(new Object[] {c.getID(), c.getCaseId(), c.getName(), c.getTypeId(), c.getDateOpened(), c.getLastModified(), c.getUserId(), c.isClosed() ? "closed" : "open"});
}
} else {
//Case defined.
try {
Case c = storage.getRecordForValue(ACase.INDEX_CASE_ID, uri.getLastPathSegment());
retCursor.addRow(new Object[] {c.getID(), c.getCaseId(), c.getName(), c.getTypeId(), c.getDateOpened(), c.getLastModified(), c.getUserId(), c.isClosed() ? "closed" : "open"});
} catch(NoSuchElementException nsee) {
//No cases with a matching index.
return retCursor;
}
}
return retCursor;
}
/**
* Query the casedb for the key/value pairs for a specific case.
*
* @return
*/
private Cursor queryCaseData(String caseId, String[] projection, String selection, String[] selectionArgs, String sortOrder) {
//Demo only, we'll pull this out when we're doing this for real and centralize it/manage its lifecycle more carefully
SqlStorage<ACase> storage = CommCareApplication._().getUserStorage(ACase.STORAGE_KEY, ACase.class);
//Default projection.
MatrixCursor retCursor = new MatrixCursor(new String[] {CaseDataAPI.DataColumns._ID,
CaseDataAPI.DataColumns.CASE_ID,
CaseDataAPI.DataColumns.DATUM_ID,
CaseDataAPI.DataColumns.VALUE});
Case c;
try {
c = storage.getRecordForValue(ACase.INDEX_CASE_ID, caseId);
} catch(NoSuchElementException nsee) {
//No cases with a matching index.
return retCursor;
}
int i = 0;
Hashtable<String, String> properties = c.getProperties();
for(String key : properties.keySet()) {
retCursor.addRow(new Object[] {i, caseId, key, c.getPropertyString(key)});
++i;
}
return retCursor;
}
/** All of the below are invalid due to the read-only nature of the content provider. It's not 100% clear from spec how to express
* the read-only-ness. **/
/* (non-Javadoc)
* @see android.content.ContentProvider#update(android.net.Uri, android.content.ContentValues, java.lang.String, java.lang.String[])
*/
@Override
public int update(Uri uri, ContentValues values, String selection,String[] selectionArgs) {
// Case content provider is read only.
//TODO: Throw an exception here? Read up on the spec
return 0;
}
/* (non-Javadoc)
* @see android.content.ContentProvider#delete(android.net.Uri, java.lang.String, java.lang.String[])
*/
@Override
public int delete(Uri uri, String selection, String[] selectionArgs) {
// Case content provider is read only.
return 0;
}
/* (non-Javadoc)
* @see android.content.ContentProvider#insert(android.net.Uri, android.content.ContentValues)
*/
@Override
public Uri insert(Uri uri, ContentValues values) {
// TODO Auto-generated method stub
return null;
}
}