<?php
//Действия с базой данных согласно json файлу.

class Database_JsonInstall {
    public $db_manager;
    public $serialColumns;

	public function __construct(Database_Manager $db_manager) {
		$this->db_manager = $db_manager;
	}

	function install($dbinit_path, $dbfill_path = null) {
		$dbinit_file = file_get_contents($dbinit_path);
		if (is_string($dbinit_file)) {
			$initActions = json_decode($dbinit_file, true);
			if (!$initActions) {
				echo "Invalid dbinit.json ".$dbinit_file;
				return 0;
			}
		} else {
			echo "No dbinit.json";
			return 0;
		}

		$this->initDataBase($initActions, $dbinit_path);
		if ($dbfill_path) {
			$this->fillDataBase($dbfill_path);
		}
		$this->makeConstraints($initActions);
	}

	function missingTables($tables) {
		$actual_tables = $this->db_manager->GetAllTableNames();
		$missingTables = [];
		foreach ($tables as $table) {
			if (!in_array($table, $actual_tables))
				$missingTables[] = $table;
		}
		return $missingTables;
	}

	//Создать таблицы
	function initDataBase(/*.array.*/$initActions, $dbinit_path) {
		$pg = $this->db_manager->db->isPostgres();
		if (!$pg) {
			$refs = [];
			//В sqlite нет alter reference. Референсы надо создавать при создании таблицы.
			foreach ($initActions as $action) {
				if ($action["type"] == "alterReference") {
					if (!isset($refs[$action["table"]]))
						$refs[$action["table"]] = [];
					$refs[$action["table"]][]=$action;//добавить к списку референсов для таблицы
				}
			}
		}

		foreach ($initActions as $action) {
			if (!$pg) {
				if ($action["type"] == "createTable") {
					$table_name = $action["table_name"];
					if (isset($refs[$table_name])) {
						foreach ($refs[$table_name] as $value) {
							$action['fields'][$value['column']]['references'] =
							$value['refTable']."(".$value['refColumn'].")";
						}
					}

				}
			}
			if ($action["type"] != "alterReference") {
				$this->db_manager->ExecuteAction($action, $dbinit_path);
			}
		}

		//Запомнить все колонки serial
		$this->serialColumns = [];
		if ($pg) {
			foreach ($initActions as $action) {
				if ($action["type"] == "createTable") {
					foreach ($action["fields"] as $name => $field) {
						if ($field["type"]=="serial") {
							$this->serialColumns[] = [
                                "table"=>$action["table_name"],
								"column"=>$name
                            ];
						}
					}
				}
			}
		}
	}

	//Заполнить данными
	function fillDataBase($dbfill_file_path) {
		$dbfill_file = file_get_contents($dbfill_file_path);
		if (is_string($dbfill_file)) {
			$actions = json_decode($dbfill_file,true);
			if ($actions) {
				
				//Проверка что упоминаемые в списке действий таблицы уже есть в базе
				$affected_tables = [];
				foreach ($actions as $action) {
					if ($action["table_name"]) {
						$affected_tables[$action["table_name"]] = 1;
                    }
                }

				$missing = $this->missingTables(array_keys($affected_tables));
				if (!empty($missing)) {
					echo "dbfill error. Missing tables: ".implode(" ", $missing);
					return;
				}

				//Выполнение действий
				foreach ($actions as $action) {
					$this->db_manager->ExecuteAction($action, $dbfill_file_path);
				}
			} else {
				echo "Invalid dbfill.json";
			}
		} else {
			echo "No dbfill.json";
		}
	}

	//Обновить ключи serial и создать ограничения
	function makeConstraints($initActions) {
		$pg = $this->db_manager->db->isPostgres();
		if ($pg) {
			foreach ($this->serialColumns as $serialColumn) {
				$this->db_manager->UpdateSerial($serialColumn["table"], $serialColumn["column"]);
			}
		
			
			foreach ($initActions as $action) {
				if ($action["type"] == "alterReference") {
					$this->db_manager->ExecuteAction($action);
                }
			}
		}
	}

}