/**
 * Copyright (c) 2012 Todoroo Inc
 *
 * See the file "LICENSE" for the full license governing this code.
 */
package com.todoroo.astrid.data;

import android.content.ContentValues;
import android.content.Context;
import android.database.SQLException;

import com.todoroo.andlib.data.ContentResolverDao;
import com.todoroo.andlib.data.TodorooCursor;
import com.todoroo.andlib.sql.Criterion;
import com.todoroo.andlib.sql.Field;
import com.todoroo.andlib.sql.Functions;
import com.todoroo.andlib.sql.Query;
import com.todoroo.astrid.api.PermaSql;

/**
 * Data access object for accessing Astrid's {@link Task} table. If you
 * are looking to store extended information about a Task, you probably
 * want to use the {@link MetadataApiDao} object.
 *
 * @author Tim Su <tim@todoroo.com>
 *
 */
public class TaskApiDao extends ContentResolverDao<Task> {

    public TaskApiDao(Context context) {
        super(Task.class, context, Task.CONTENT_URI);
    }

    /**
     * Generates SQL clauses
     */
    public static class TaskCriteria {

        /** @return tasks by id */
        public static Criterion byId(long id) {
            return Task.ID.eq(id);
        }

        /** @return tasks that were deleted */
        public static Criterion isDeleted() {
            return Task.DELETION_DATE.neq(0);
        }

        /** @return tasks that were not deleted */
        public static Criterion notDeleted() {
            return Task.DELETION_DATE.eq(0);
        }

        /** @return tasks that have not yet been completed or deleted */
        public static Criterion activeAndVisible() {
            return Criterion.and(Task.COMPLETION_DATE.eq(0),
                    Task.DELETION_DATE.eq(0),
                    Task.HIDE_UNTIL.lt(Functions.now()));
        }

        /** @return tasks that have not yet been completed or deleted */
        public static Criterion isActive() {
            return Criterion.and(Task.COMPLETION_DATE.eq(0),
                    Task.DELETION_DATE.eq(0));
        }

        /** @return tasks that are not hidden at current time */
        public static Criterion isVisible() {
            return Task.HIDE_UNTIL.lt(Functions.now());
        }

        /** @return tasks that have a due date */
        public static Criterion hasDeadlines() {
            return Task.DUE_DATE.neq(0);
        }

        /** @return tasks that are due before a certain unixtime */
        public static Criterion dueBeforeNow() {
            return Criterion.and(Task.DUE_DATE.gt(0), Task.DUE_DATE.lt(Functions.now()));
        }

        /** @return tasks that are due after a certain unixtime */
        public static Criterion dueAfterNow() {
            return Task.DUE_DATE.gt(Functions.now());
        }

        /** @return tasks completed before a given unixtime */
        public static Criterion completed() {
            return Criterion.and(Task.COMPLETION_DATE.gt(0), Task.COMPLETION_DATE.lt(Functions.now()));
        }

        /** @return tasks that have a blank or null title */
        @SuppressWarnings("nls")
        public static Criterion hasNoTitle() {
            return Criterion.or(Task.TITLE.isNull(), Task.TITLE.eq(""));
        }

        /** @return tasks that have not yet been completed or deleted */
        public static Criterion activeVisibleMine() {
            return Criterion.and(Task.COMPLETION_DATE.eq(0),
                    Task.DELETION_DATE.eq(0),
                    Task.HIDE_UNTIL.lt(Functions.now()),
                    Field.field(Task.FLAGS.name + " & " + //$NON-NLS-1$
                            Task.FLAG_IS_READONLY).eq(0),
                    Task.USER_ID.eq(0));
        }

        /** Check if a given task belongs to someone else & is read-only */
        public static Criterion ownedByMe() {
             return Criterion.and(Field.field(Task.FLAGS.name+ " & " + //$NON-NLS-1$
                     Task.FLAG_IS_READONLY).eq(0),
                     Task.USER_ID.eq(0));
        }

    }

    /**
     * Count tasks matching criterion
     * @param criterion
     * @return # of tasks matching
     */
    public int countTasks(Criterion criterion) {
        TodorooCursor<Task> cursor = query(Query.select(Task.ID).where(criterion));
        try {
            return cursor.getCount();
        } finally {
            cursor.close();
        }
    }

    /**
     * Count tasks matching query tepmlate
     * @param queryTemplate
     * @return # of tasks matching
     */
    public int countTasks(String queryTemplate) {
        queryTemplate = PermaSql.replacePlaceholders(queryTemplate);
        TodorooCursor<Task> cursor = query(Query.select(Task.ID).withQueryTemplate(queryTemplate));
        try {
            return cursor.getCount();
        } finally {
            cursor.close();
        }
    }

    @Override
    public boolean save(Task model) {
        try {
            return super.save(model);
        } catch (SQLException e) {
            if (model.containsNonNullValue(Task.REMOTE_ID)) {
                TodorooCursor<Task> cursor = query(Query.select(Task.ID).where(Task.REMOTE_ID.eq(model.getValue(Task.REMOTE_ID))));
                if (cursor.getCount() > 0) {
                    cursor.moveToFirst();
                    model.setId(cursor.get(Task.ID));
                    return super.save(model);
                }
            }
        }
        return false;
    }

    /** @return true if task change shouldn't be broadcast */
    public static boolean insignificantChange(ContentValues values) {
        if(values == null || values.size() == 0)
            return true;

        if(values.containsKey(Task.DETAILS_DATE.name) &&
                values.size() <= 3)
            return true;

        if(values.containsKey(Task.REMINDER_LAST.name) &&
                values.size() <= 2)
            return true;

        if(values.containsKey(Task.REMINDER_SNOOZE.name) &&
                values.size() <= 2)
            return true;

        if(values.containsKey(Task.TIMER_START.name) &&
                values.size() <= 2)
            return true;

        return false;
    }

}