<?php
namespace mcoop;

class TableCreationError extends \Exception {
	public $table_name = null;
	public $sql_error_code = null;
	public $server_error_code = null;
	public $server_error_message = null;

	function __construct($table_name, $sql_error_code, $server_error_code, $server_error_message) {
		$this->table_name = $table_name;
		$this->sql_error_code = $sql_error_code;
		$this->server_error_code = $server_error_code;
		$this->server_error_message = $server_error_message;

		$message = "Failed to create table '$table_name': ($sql_error_code, $server_error_code, $server_error_message)";
		parent::__construct($message);
	}
}

interface TableUpgrader {
	function upgrade($from_version, $to_version);
}

class BaseIncrementalTableUpgrader implements TableUpgrader {
	public $upgrade_method_names = array();
	public $table_name = null;
	public $conn = null;

	function upgrade($from_version, $to_version) {
		// first make sure a full update is possible with what's in method_names
		$full_upgrade_path = true;
		for ($i = $from_version + 1; $i <= $to_version; $i++) {
			$method_name = $this->upgrade_method_names[$i];
			if (!is_callable(array($this, $method_name))) {
				$full_upgrade_path = false;
				error_log(get_class($this) . "::upgrade_method_names for $i not callable: " . var_export($method_name, true));
			}
		}
		if (!$full_upgrade_path) {
			die("couldn't upgrade the database, check error_log");
		} else {
			$highest_version = $from_version;
			for ($i = $from_version + 1; $i <= $to_version; $i++) {
				$method_name = $this->upgrade_method_names[$i];
				// XXX/TODO: this really needs trying around, not sure how to deal with upgrades that fail though, might want a downgrade function to rollback if you fail somewhere between, or just leave it in the middle state
				$this->$method_name();
				$highest_version = $i;
			}
			return $highest_version;
		}
	}
}

class SimpleTableDecl {
	public $table_name = null;
	public $statements_sql = array();
	// it might make sense to make this an array in the future, but for now just make it a simple string for creating the newest version
	public $create_table_sql = null;
	public $newest_tableversion = null; // int
	public $upgrader_classname = null; // string, this should be fully namespaced so it can be created dynamically
	// TODO: table dependencies variables for creating and/or for the statements?

	function create_table($db) {
		$conn = $db->conn;
		$conn->exec($this->create_table_sql);
		$err_info = $conn->errorInfo();
		// the SQL errorcode for a table already existing seems to be 42S01
		// but I think we don't need to check for it specifically here,
		// just make sure there was no error
		//print_r($err_info);
		//var_dump($err_info);
		if ($err_info[0] == "00000") {
			$db->statements["set_tableversion"]->execute(array(
				":table_name" => $this->table_name,
				":version" => $this->newest_tableversion
			));
		} else if ($err_info[0] != "42S01") {
			$db->statements["insert_unexpected_error"]->execute(array(
				":action" => "create_table($this->table_name)",
				":sql_code" => $err_info[0],
				":server_code" => $err_info[1],
				":server_description" => $err_info[2]
			));
			throw new TableCreationError($this->table_name, $err_info[0], $err_info[1], $err_info[2]);
		}
	}

	function set_statements($db) {
		foreach ($this->statements_sql as $name => $sql) {
			if (array_key_exists($name, $db->statements)) {
				// TODO: I should probably also raise an exception here
				error_log("mcoop: table_decl for $this->table_name: key $name already exists in the db's statements, not replacing");
			} else {
				$db->statements[$name] = $db->conn->prepare($sql);
			};
		}
	}

	function __construct($table_name, $statements_sql, $create_table_sql, $newest_tableversion, $upgrader_classname) {
		$this->table_name = $table_name;
		$this->statements_sql = $statements_sql;
		$this->create_table_sql = $create_table_sql;
		$this->newest_tableversion = $newest_tableversion;
		$this->upgrader_classname = $upgrader_classname;
	}
}

class SimpleDBMixin {
	static function load_mult_with_statement($db, $st_name, $varray, $clsname=null, $keyprop=null) {
		if ($clsname == null)
			$clsname = get_called_class();
		$st = $db->statements[$st_name];
		$st->execute($varray);
		$ret = array();
		$last_obj = null;
		do {
			$last_obj = $st->fetchObject($clsname);
			//var_dump($st_name, $varray, $clsname, $keyprop, $st, $last_obj);
			//var_dump($clsname);
			if ($last_obj != FALSE) {
				if ($keyprop) {
					$key = $last_obj->$keyprop;
					// TODO: deal with duplicates
					$ret[$key] = $last_obj;
				} else {
					$ret[] = $last_obj;
				}
			}
		} while ($last_obj != FALSE);
		return $ret;
	}
}

// TODO: all of these classes need a get_json function so you don't serialize the entire thing (or look at how to override json
// serialization for classes/objects again)

class DBMember extends SimpleDBMixin {
	// from the members table:
	//public $db = null;
	public $userid = null;
	public $username = null;
	public $email = null;
	public $last_updated_table_version = null;
	public $full_name = null;
	public $validation_code = null;
	public $validated = null;
	public $full_member = null;
	public $argon2_password_hash = null;
	public $reset_password_hash = null;
	public $reset_requested = null;
	// from the shares table:
	//public $shares = array();
	// generated in __construct
	public $display_name = null;

	function __construct() {
		if (isset($this->full_name) && $this->full_name)
			$this->display_name = $this->full_name;
		else
			$this->display_name = $this->username;
	}

	static function load_by($db, $by, $value) {
		// by should be either "username" or "email" here
		$st = $db->statements["get_member_by_$by"];
		$st->execute(array($value));
		$self = $st->fetchObject("\mcoop\DBMember");
		if (!$self) {
			throw new UnknownMember($by, $value);
		}
		//$self->db = $db;
		return $self;
	}

	static function load_public_info($db, $userid) {
		$ret = DBMember::load_mult_with_statement($db, "get_public_member_info_by_userid", array(":userid" => $userid));
		if (!$ret) {
			throw new UnknownMember("userid", $userid);
		} else {
			//$ret[0]->db = $db;
			return $ret[0];
		}
	}
}

class TccHistoryEntry extends SimpleDBMixin {
	// tcc_history table values
	public $from_tdc_id = null; // this should probably index into a table in the task object
	public $to_claim_id = null; // contains this object, sometimes (the tdc could also contain them, hmm)
	public $action = null;
	public $credits = null;
	public $last_updated_table_version = null;

	static function get_history_by_claimid($db, $claimid, $clsname=null, $keyprop=null) {
		return TccHistoryEntry::load_mult_with_statement($db, "get_tcc_history_by_claimid", array(":claimid" => $claimid), $clsname, $keyprop);
	}

	static function get_history_by_tdc_id($db, $tdc_id, $clsname=null, $keyprop=null) {
		return TccHistoryEntry::load_mult_with_statement($db, "get_tcc_history_by_tdc_id", array(":tdc_id" => $tdc_id), $clsname, $keyprop);
	}
}


class SimpleTaskClaim extends SimpleDBMixin {
	// claims table values
	public $claim_id = null;
	public $task_id = null;
	public $userid = null;
	public $last_updated_table_version = null;
	public $description = null;
	// loaded via. userid
	public $member_public = null;
	// loaded from tcc_history, see $this->load_tcc_history
	public $tcc_history = null;

	static function get_claims_by_taskid($db, $taskid, $clsname=null, $keyprop=null) {
		return SimpleTaskClaim::load_mult_with_statement($db, "get_task_claims_by_taskid", array(":task_id" => $taskid), $clsname, $keyprop);
	}

	function load_member($db) {
		$this->member_public = DBMember::load_public_info($db, $this->userid);
	}

	function load_tcc_history($db) {
		$this->tcc_history = TccHistoryEntry::get_history_by_claimid($db, $this->claim_id);
	}

	function load_all($db) {
		$this->load_member($db);
		$this->load_tcc_history($db);
	}
}

class SimpleTdc extends SimpleDBMixin {
	// tdc table values
	public $tdc_id = null;
	public $task_id = null;
	public $posted_userid = null;
	public $posted_by_coop = null;
	public $total_credits = null;
	public $remaining_credits = null;
	public $last_updated_table_version = null;
	// loaded via. posted_userid, will be null after $this->load_member() if posted_by_coop is true
	public $member_public = null;
	// Set to either $member_public->display_name or "By the Co-Operative"
	// TODO: maybe use the website_name in $config with posted_by_coop
	public $member_name = null;

	static function get_tdcs_by_taskid($db, $taskid, $clsname=null, $keyprop=null) {
		return SimpleTdc::load_mult_with_statement($db, "get_tdcs_by_taskid", array(":task_id" => $taskid), $clsname, $keyprop);
	}

	function load_member($db) {
		if ($this->posted_by_coop) {
			$this->member_name = "By the Co-Operative";
		} else {
			$this->member_public = DBMember::load_public_info($db, $this->posted_userid);
			$this->member_name = $this->member_public->display_name;
		}
	}

	function load_all($db) {
		$this->load_member($db);
	}
}

class SimpleTask extends SimpleDBMixin {
	// tasks table values
	public $taskid = null;
	public $admin_userid = null;
	public $last_updated_table_version = null;
	public $title = null;
	public $description = null;
	public $state = null;
	// loaded via. admin_userid (DBMember with userid, username and full_name filled in, see $this->load_admin -- using a join might also be a good idea but then you have to replicate the display_name code or change DBMember's construct to pass in args directly)
	public $member_public = null;
	// loaded from task_dividend_credits, see $this->load_tdcs()
	public $tdcs = null;
	// loaded from task_claims, see $this->load_claims() or $this->load_full()
	public $claims = null;

	static function get_all_simple($db, $clsname=null, $keyprop=null) {
		return SimpleTask::load_mult_with_statement($db, "get_all_tasks_simple", array(), $clsname, $keyprop);
	}

	static function get_all_full($db, $clsname=null, $keyprop=null) {
		return SimpleTask::load_mult_with_statement($db, "get_all_tasks", array(), $clsname, $keyprop);
	}

	function load_admin($db) {
		$this->member_public = DBMember::load_public_info($db, $this->admin_userid);
	}

	function load_claims($db, $full) {
		$this->claims = SimpleTaskClaim::get_claims_by_taskid($db, $this->taskid, null, "claim_id");
		if ($full) {
			foreach ($this->claims as $k => $claim) {
				$claim->load_all($db);
			}
		}
	}

	function load_tdcs($db, $full) {
		$this->tdcs = SimpleTdc::get_tdcs_by_taskid($db, $this->taskid, null, "tdc_id");
		if ($full) {
			foreach ($this->tdcs as $k => $tdc) {
				$tdc->load_all($db);
			}
		}
	}

	function load_all($db) {
		$this->load_admin($db);
		$this->load_tdcs($db, true);
		$this->load_claims($db, true);
	}
}

class SessionInfo {
	public $db = null;
	public $login_member = null;

	function __construct($db, $logout) {
		$this->db = $db;
		session_start();
		if ($logout) {
			$this->logout();
		}
		$this->re_init();
	}

	function logout() {
		session_unset();
		$this->login_member = null;
	}

	function re_init() {
		$this->login_member = null;
		if (isset($_SESSION["logged_in"]) && $_SESSION["logged_in"] && isset($_SESSION["login_username"])) {
			// TODO: validate login, either based on password, password reset time or possibly allow users to log out sessions explicitly (might require database session storage to make it easier)
			$this->login_member = DBMember::load_by($this->db, "username", $_SESSION["login_username"]);
		}
	}
}
?>