<?php
	class Version
	{
		private $db;
		private $changelog;
		private $err;
		private $userid;
		public $zend_db;
		
		//初始化
		function __construct($config)
		{
			//$this->db=$config->db;
			$this->versionTable=$config->versionTable;
			$this->changelog=$config->changelog;
			$this->db = pg_connect(http_build_query($config->db,'',' '));
			$this->err=array();
			$this->userid=$config->userid;
		}
		
		function __destruct()
		{
			pg_close($this->db);
		}
		
		//版本更新：指定versionid
		function update_by_version($uuid,$versionid,$changelog="")
		{
			if (!$changelog) $changelog=$this->changelog;
			// 1. 保存变化记录 save changelog & userid
			$sql = "UPDATE {$this->versionTable} SET changelog='$changelog',userid=$this->userid WHERE id=$versionid and uuid='$uuid'";
			pg_query($this->db,$sql);

			// 2. 同步元数据
			$sql = "select xml from {$this->versionTable} where id=$versionid and uuid='$uuid'";
			$result=pg_query($this->db,$sql);
			$row = pg_fetch_row($result);
			$iso=new ISO19115();
			@$iso->loadXML($row[0]);
			if ($iso->validate())
			{
				$this->err[]="元数据: ".$uuid." 导入过程中发现错误。\n".implode("\n",$iso->error);
			}
			@$iso->saveDB($this->zend_db);
				
			// 3. 移除中间版本
			$sql="delete from {$this->versionTable} where uuid='$uuid' and changelog is null";
			pg_query($this->db,$sql);
			pg_free_result($result);
		}
		
		//版本更新：以最新的一个版本进行更新
		function update_by_uuid($uuid,$changelog="")
		{
			if (!$changelog) $changelog=$this->changelog;
			// 1. 保存变化记录 save changelog & userid
			$sql = "UPDATE {$this->versionTable} SET changelog='$changelog',userid=$this->userid WHERE id in (select id from {$this->versionTable} where uuid='$uuid' order by ts_created desc limit 1)";
			pg_query($this->db,$sql);

			// 2. 同步元数据
			$sql = "select xml from {$this->versionTable} where uuid='$uuid' order by ts_created desc limit 1";
			$result=pg_query($this->db,$sql);
			$row = pg_fetch_row($result);
			$iso=new ISO19115();
			@$iso->loadXML($row[0]);
			if ($iso->validate())
			{
				$this->err[]="元数据: ".$uuid." 导入过程中发现错误。\n".implode("\n",$iso->error);
			}
			@$iso->saveDB($this->zend_db);
				
			// 3. 移除中间版本
			$sql="delete from {$this->versionTable} where uuid='$uuid' and changelog is null";
			pg_query($this->db,$sql);
			pg_free_result($result);
		}
		
		//专题更新：将指定专题的数据，全部按照最新版本进行更新
		function update_by_source($sourceid,$changelog="")
		{
			if (!$changelog) $changelog=$this->changelog;
			// 1. 保存变化记录 save changelog & userid
			$sql = "UPDATE {$this->versionTable} SET changelog='$changelog',userid=$this->userid WHERE id in (
				select distinct on (uuid) id from {$this->versionTable} where uuid in (select uuid from datasource where sourceid=$sourceid) order by uuid,ts_created desc
				)";
			pg_query($this->db,$sql);

			// 2. 同步元数据
			$sql = "select xml from {$this->versionTable} WHERE id in (
				select distinct on (uuid) id from {$this->versionTable} where uuid in (select uuid from datasource where sourceid=$sourceid) order by uuid,ts_created desc
				)";
			$result=pg_query($this->db,$sql);
			while ($row = pg_fetch_row($result))
			{
				$iso=new ISO19115();
				@$iso->loadXML($row[0]);
				if ($iso->validate())
				{
					$this->err[]="元数据: ".$uuid." 导入过程中发现错误。\n".implode("\n",$iso->error);
				}
				@$iso->saveDB($this->zend_db);
			}	
			// 3. 移除中间版本
			$sql="delete from {$this->versionTable} where uuid in (select distinct uuid from datasource where sourceid=$sourceid) and changelog is null";
			pg_query($this->db,$sql);
			pg_free_result($result);
		}
		
		//版本删除
		function delete($uuid,$versionid)
		{
			$sql = "DELETE FROM {$this->versionTable} WHERE uuid='$uuid' and id=$versionid";
			return pg_query($this->db, $sql);
		}
		
		//todo: 版本直接发布（仅发布之前为评审状态的数据）
		function release_by_version($uuid,$versionid)
		{
			//todo
			$sql = "SELECT s.*,v.xml,m.title FROM en.mdstatus s left join en.mdversion v on s.uuid=v.uuid
					left join en.metadata m on s.uuid=m.uuid WHERE v.id=?";
			return pg_query($this->db,$sql);
		}
		function release_by_uuid($uuid)
		{
			//todo
		}
		function release_by_source($sourceid)
		{
			//todo
		}
		
		//错误输出
		function error()
		{
			if (!empty($this->err))
			{
				foreach($this->err as $e) print $e;
			}
		}
	}