using System;
using System.Collections.Generic;
using System.Text;

using OpenSim.Framework.Console;
using OpenSim.Framework.Types;
using OpenSim.Framework.Utilities;
using libsecondlife;

using System.Data;
using System.Data.SqlTypes;

using Mono.Data.SqliteClient;

namespace OpenSim.Framework.Data.SQLite
{

    public class SQLiteInventoryStore : IInventoryData
    {
        private const string invItemsSelect = "select * from inventoryitems";
        private const string invFoldersSelect = "select * from inventoryfolders";

        private DataSet ds;
        private SqliteDataAdapter invItemsDa;
        private SqliteDataAdapter invFoldersDa;

        /// <summary>
        /// Initialises the interface
        /// </summary>
        public void Initialise()
        {
            Initialise("inventoryStore.db", "inventoryDatabase");
        }

        public void Initialise(string dbfile, string dbname)
        {
            string connectionString = "URI=file:" + dbfile + ",version=3";

            MainLog.Instance.Verbose("Inventory", "Sqlite - connecting: " + dbfile);
            SqliteConnection conn = new SqliteConnection(connectionString);

            SqliteCommand itemsSelectCmd = new SqliteCommand(invItemsSelect, conn);
            invItemsDa = new SqliteDataAdapter(itemsSelectCmd);
            //            SqliteCommandBuilder primCb = new SqliteCommandBuilder(primDa);

            SqliteCommand foldersSelectCmd = new SqliteCommand(invFoldersSelect, conn);
            invFoldersDa = new SqliteDataAdapter(foldersSelectCmd);

            ds = new DataSet();

            invItemsDa.Fill(ds, "inventoryitems");
            invFoldersDa.Fill(ds, "inventoryfolders");
            ds.AcceptChanges();

            DataTable itemsTable = ds.Tables["inventoryitems"];
            itemsTable.PrimaryKey = new DataColumn[] { itemsTable.Columns["UUID"] };
            setupItemsCommands(invItemsDa, conn);

            // shapeDa.FillSchema(ds, SchemaType.Source, "ShapeSchema");
            DataTable folderTable = ds.Tables["inventoryfolders"];
            folderTable.PrimaryKey = new DataColumn[] { folderTable.Columns["UUID"] };
            setupFoldersCommands(invFoldersDa, conn);
            return;
        }

        private SqliteParameter createSqliteParameter(string name, DbType type)
        {
            SqliteParameter param = new SqliteParameter();
            param.ParameterName = ":" + name;
            param.DbType = type;
            param.SourceColumn = name;
            param.SourceVersion = DataRowVersion.Current;
            return param;
        }

        private Dictionary<string, DbType> createInventoryItemsDataDefs()
        {
            Dictionary<string, DbType> data = new Dictionary<string, DbType>();
            data.Add("UUID", DbType.String); //inventoryID
            data.Add("assetID", DbType.String);
            data.Add("assetType", DbType.Int32);
            data.Add("invType", DbType.Int32);
            data.Add("parentFolderID", DbType.String);
            data.Add("avatarID", DbType.String);
            data.Add("creatorsID", DbType.String);

            data.Add("inventoryName", DbType.String);
            data.Add("inventoryDescription", DbType.String);
            // permissions
            data.Add("inventoryNextPermissions", DbType.Int32);
            data.Add("inventoryCurrentPermissions", DbType.Int32);
            data.Add("inventoryBasePermissions", DbType.Int32);
            data.Add("inventoryEveryOnePermissions", DbType.Int32);

            return data;
        }

        private Dictionary<string, DbType> createShapeDataDefs()
        {
            Dictionary<string, DbType> data = new Dictionary<string, DbType>();
            data.Add("UUID", DbType.String); //folderID
            // shape is an enum
            data.Add("name", DbType.String);
            // vectors
            data.Add("agentID", DbType.String);
            data.Add("parentID", DbType.String);
            data.Add("type", DbType.Int32);
            data.Add("version", DbType.Int32);
            return data;
        }

        private SqliteCommand createInsertCommand(string table, Dictionary<string, DbType> defs)
        {
            /**
             *  This is subtle enough to deserve some commentary.
             *  Instead of doing *lots* and *lots of hardcoded strings
             *  for database definitions we'll use the fact that
             *  realistically all insert statements look like "insert
             *  into A(b, c) values(:b, :c) on the parameterized query
             *  front.  If we just have a list of b, c, etc... we can
             *  generate these strings instead of typing them out.
             */
            string[] cols = new string[defs.Keys.Count];
            defs.Keys.CopyTo(cols, 0);

            string sql = "insert into " + table + "(";
            sql += String.Join(", ", cols);
            // important, the first ':' needs to be here, the rest get added in the join
            sql += ") values (:";
            sql += String.Join(", :", cols);
            sql += ")";
            SqliteCommand cmd = new SqliteCommand(sql);

            // this provides the binding for all our parameters, so
            // much less code than it used to be
            foreach (KeyValuePair<string, DbType> kvp in defs)
            {
                cmd.Parameters.Add(createSqliteParameter(kvp.Key, kvp.Value));
            }
            return cmd;
        }

        private SqliteCommand createUpdateCommand(string table, string pk, Dictionary<string, DbType> defs)
        {
            string sql = "update " + table + " set ";
            string subsql = "";
            foreach (string key in defs.Keys)
            {
                if (subsql.Length > 0)
                { // a map function would rock so much here
                    subsql += ", ";
                }
                subsql += key + "= :" + key;
            }
            sql += subsql;
            sql += " where " + pk;
            SqliteCommand cmd = new SqliteCommand(sql);

            // this provides the binding for all our parameters, so
            // much less code than it used to be
            foreach (KeyValuePair<string, DbType> kvp in defs)
            {
                cmd.Parameters.Add(createSqliteParameter(kvp.Key, kvp.Value));
            }
            return cmd;
        }

        private void setupItemsCommands(SqliteDataAdapter da, SqliteConnection conn)
        {
            Dictionary<string, DbType> invDataDefs = createInventoryItemsDataDefs();

            da.InsertCommand = createInsertCommand("inventoryitems", invDataDefs);
            da.InsertCommand.Connection = conn;

            da.UpdateCommand = createUpdateCommand("inventoryitems", "UUID=:UUID", invDataDefs);
            da.UpdateCommand.Connection = conn;

            SqliteCommand delete = new SqliteCommand("delete from inventoryitems where UUID = :UUID");
            delete.Parameters.Add(createSqliteParameter("UUID", DbType.String));
            delete.Connection = conn;
            da.DeleteCommand = delete;
        }

        private void setupFoldersCommands(SqliteDataAdapter da, SqliteConnection conn)
        {
            Dictionary<string, DbType> shapeDataDefs = createShapeDataDefs();

            da.InsertCommand = createInsertCommand("inventoryfolders", shapeDataDefs);
            da.InsertCommand.Connection = conn;

            da.UpdateCommand = createUpdateCommand("inventoryfolders", "UUID=:UUID", shapeDataDefs);
            da.UpdateCommand.Connection = conn;

            SqliteCommand delete = new SqliteCommand("delete from inventoryfolders where UUID = :UUID");
            delete.Parameters.Add(createSqliteParameter("UUID", DbType.String));
            delete.Connection = conn;
            da.DeleteCommand = delete;
        }

        private InventoryFolderBase buildFolder(DataRow row)
        {
            InventoryFolderBase folder = new InventoryFolderBase();
            folder.folderID = new LLUUID((string)row["UUID"]);
            folder.name = (string)row["name"];
            folder.agentID = new LLUUID((string)row["agentID"]);
            folder.parentID = new LLUUID((string)row["parentID"]);
            folder.type = Convert.ToInt16(row["type"]);
            folder.version = Convert.ToUInt16(row["version"]);
            return folder;
        }

        private void fillFolderRow(DataRow row, InventoryFolderBase folder)
        {
            row["UUID"] = folder.folderID;
            row["name"] = folder.name;
            row["agentID"] = folder.agentID;
            row["parentID"] = folder.parentID;
            row["type"] = folder.type;
            row["version"] = folder.version;
        }

        public InventoryItemBase BuildItem(DataRow row)
        {
            InventoryItemBase item = new InventoryItemBase();
            item.inventoryID = new LLUUID((string)row["UUID"]);
            item.assetID = new LLUUID((string)row["assetID"]);
            item.assetType = Convert.ToInt32(row["assetType"]);
            item.invType = Convert.ToInt32(row["invType"]);
            item.parentFolderID = new LLUUID((string)row["parentFolderID"]);
            item.avatarID = new LLUUID((string)row["avatarID"]);
            item.creatorsID = new LLUUID((string)row["creatorsID"]);
            item.inventoryName =(string) row["inventoryName"];
            item.inventoryDescription = (string) row["inventoryDescription"];

            item.inventoryNextPermissions = Convert.ToUInt32(row["inventoryNextPermissions"]);
            item.inventoryCurrentPermissions = Convert.ToUInt32(row["inventoryCurrentPermissions"]);
            item.inventoryBasePermissions = Convert.ToUInt32(row["inventoryBasePermissions"]);
            item.inventoryEveryOnePermissions = Convert.ToUInt32(row["inventoryEveryOnePermissions"]);
            return item;
        }

        private void fillItemRow(DataRow row, InventoryItemBase item)
        {
            row["UUID"] = item.inventoryID;
            row["assetID"] = item.assetID;
            row["assetType"] = item.assetType;
            row["invType"] = item.invType;
            row["parentFolderID"] = item.parentFolderID;
            row["avatarID"] = item.avatarID;
            row["creatorsID"] = item.creatorsID;
            row["inventoryName"] = item.inventoryName;
            row["inventoryDescription"] = item.inventoryDescription;

            row["inventoryNextPermissions"] = item.inventoryNextPermissions;
            row["inventoryCurrentPermissions"] = item.inventoryCurrentPermissions;
            row["inventoryBasePermissions"] = item.inventoryBasePermissions;
            row["inventoryEveryOnePermissions"] = item.inventoryEveryOnePermissions;
        }

        private void addFolder(InventoryFolderBase folder)
        {
            DataTable inventoryFolderTable = ds.Tables["inventoryfolders"];

            DataRow inventoryRow = inventoryFolderTable.Rows.Find(folder.folderID);
            if (inventoryRow == null)
            {
                inventoryRow = inventoryFolderTable.NewRow();
                fillFolderRow(inventoryRow, folder);
                inventoryFolderTable.Rows.Add(inventoryRow);
            }
            else
            {
                fillFolderRow(inventoryRow, folder);
            }

            this.invFoldersDa.Update(ds, "inventoryfolders");
        }

        private void addItem(InventoryItemBase item)
        {
            DataTable inventoryItemTable = ds.Tables["inventoryitems"];

            DataRow inventoryRow = inventoryItemTable.Rows.Find(item.inventoryID);
            if (inventoryRow == null)
            {
                inventoryRow = inventoryItemTable.NewRow();
                fillItemRow(inventoryRow, item);
                inventoryItemTable.Rows.Add(inventoryRow);
            }
            else
            {
                fillItemRow(inventoryRow, item);
            }
            this.invItemsDa.Update(ds, "inventoryitems");
        }

        public void Shutdown()
        {
            // TODO: DataSet commit
        }

        /// <summary>
        /// Closes the interface
        /// </summary>
        public void Close()
        {
        }

        /// <summary>
        /// The plugin being loaded
        /// </summary>
        /// <returns>A string containing the plugin name</returns>
        public string getName()
        {
            return "SQLite Inventory Data Interface";
        }

        /// <summary>
        /// The plugins version
        /// </summary>
        /// <returns>A string containing the plugin version</returns>
        public string getVersion()
        {
            return "0.1";
        }

        /// <summary>
        /// Returns a list of inventory items contained within the specified folder
        /// </summary>
        /// <param name="folderID">The UUID of the target folder</param>
        /// <returns>A List of InventoryItemBase items</returns>
        public List<InventoryItemBase> getInventoryInFolder(LLUUID folderID)
        {
            List<InventoryItemBase> retval = new List<InventoryItemBase>();
            DataTable inventoryItemTable = ds.Tables["inventoryitems"];
            string selectExp = "parentFolderID = '" + folderID.ToString() + "'";
            DataRow[] rows = inventoryItemTable.Select(selectExp);
            foreach (DataRow row in rows)
            {
                retval.Add(BuildItem(row));
            }

            return retval;
        }

        /// <summary>
        /// Returns a list of the root folders within a users inventory
        /// </summary>
        /// <param name="user">The user whos inventory is to be searched</param>
        /// <returns>A list of folder objects</returns>
        public List<InventoryFolderBase> getUserRootFolders(LLUUID user)
        {
            return null;
        }

        /// <summary>
        /// Returns the users inventory root folder.
        /// </summary>
        /// <param name="user">The UUID of the user who is having inventory being returned</param>
        /// <returns>Root inventory folder</returns>
        public InventoryFolderBase getUserRootFolder(LLUUID user)
        {
            List<InventoryFolderBase> folders = new List<InventoryFolderBase>();
            DataTable inventoryFolderTable = ds.Tables["inventoryfolders"];
            string selectExp = "agentID = '" + user.ToString() + "' AND parentID = '" + LLUUID.Zero.ToString() + "'";
            DataRow[] rows = inventoryFolderTable.Select(selectExp);
            foreach (DataRow row in rows)
            {
                folders.Add(this.buildFolder(row));
            }

            if (folders.Count == 1)
            {
                //we found the root
                //System.Console.WriteLine("found root inventory folder");
                return folders[0];
            }
            else if (folders.Count > 1)
            {
                //err shouldn't be more than one root
                //System.Console.WriteLine("found more than one root inventory folder");
            }
            else if (folders.Count == 0)
            {
                // no root?
                //System.Console.WriteLine("couldn't find root inventory folder");
            }

            return null;
        }

        /// <summary>
        /// Returns a list of inventory folders contained in the folder 'parentID'
        /// </summary>
        /// <param name="parentID">The folder to get subfolders for</param>
        /// <returns>A list of inventory folders</returns>
        public List<InventoryFolderBase> getInventoryFolders(LLUUID parentID)
        {
            List<InventoryFolderBase> folders = new List<InventoryFolderBase>();
            DataTable inventoryFolderTable = ds.Tables["inventoryfolders"];
            string selectExp = "parentID = '" + parentID.ToString() + "'";
            DataRow[] rows = inventoryFolderTable.Select(selectExp);
            foreach (DataRow row in rows)
            {
                folders.Add(this.buildFolder(row));
            }
            // System.Console.WriteLine("found " + folders.Count + " inventory folders");
            return folders;
        }

        /// <summary>
        /// Returns an inventory item by its UUID
        /// </summary>
        /// <param name="item">The UUID of the item to be returned</param>
        /// <returns>A class containing item information</returns>
        public InventoryItemBase getInventoryItem(LLUUID item)
        {
            return null;
        }

        /// <summary>
        /// Returns a specified inventory folder by its UUID
        /// </summary>
        /// <param name="folder">The UUID of the folder to be returned</param>
        /// <returns>A class containing folder information</returns>
        public InventoryFolderBase getInventoryFolder(LLUUID folder)
        {
            return null;
        }

        /// <summary>
        /// Creates a new inventory item based on item
        /// </summary>
        /// <param name="item">The item to be created</param>
        public void addInventoryItem(InventoryItemBase item)
        {
            this.addItem(item);
        }

        /// <summary>
        /// Updates an inventory item with item (updates based on ID)
        /// </summary>
        /// <param name="item">The updated item</param>
        public void updateInventoryItem(InventoryItemBase item)
        {
            this.addItem(item);
        }

        /// <summary>
        /// Adds a new folder specified by folder
        /// </summary>
        /// <param name="folder">The inventory folder</param>
        public void addInventoryFolder(InventoryFolderBase folder)
        {
            this.addFolder(folder);
        }

        /// <summary>
        /// Updates a folder based on its ID with folder
        /// </summary>
        /// <param name="folder">The inventory folder</param>
        public void updateInventoryFolder(InventoryFolderBase folder)
        {
            this.addFolder(folder);
        }
    }
}