package org.hwo.sql;

import java.sql.Connection;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.ArrayList;
import java.util.List;

import org.hwo.StringHelper;

public class Schema {
	
	Connection database;
	List<Table> tables;
	
	public Schema(Connection database){
		this.database = database;
		this.tables = new ArrayList<Schema.Table>();
		
		scanTables();
	}
	
	private void scanTables(){
		ResultSet rsTables;
		try {
			rsTables = database.getMetaData().getTables(null, null, null, new String[]{"TABLE"});
			while (rsTables.next()){
				tables.add(new Table(rsTables.getString("TABLE_NAME")));
			}
		} catch (SQLException e) {
			e.printStackTrace();
		}

	}
	
	
	public void print(){
		
		for (Table t: tables){
			System.err.println(t.toString());
		}
	}
	
	
	public class Table {
		private String name;
		private ArrayList<Column> columns;
		
		public Table(String name) throws SQLException{
			this.name = name;
			this.columns = new ArrayList<Schema.Table.Column>();
			scan();
		}
		public Table(){
			this.name = "";
			this.columns = new ArrayList<Schema.Table.Column>();
		}
		
		public String getName() {
			return name;
		}
		public void setName(String name) {
			this.name = name;
		}
		
		Column[] getColumns(){
			return columns.toArray(new Column[0]);
		}
		
		Column getColumn(String name){
			for (Column c: columns){
				if (c.getName().equals(name))
					return c;
			}
			return null;
		}
		
		void addColumn(Column c){
			columns.add(c);
		}
		void removeColumn(Column c){
			columns.remove(c);
		}
		void removeColumn(String name){
			columns.remove(getColumn(name));
		}
		
		private void scan() throws SQLException {
			ResultSet rsColumns = database.getMetaData().getColumns(null, null, name, null);
			
			while (rsColumns.next()){
				addColumn(new Column(rsColumns.getString("COLUMN_NAME"), rsColumns.getString("TYPE_NAME"), rsColumns.getInt("COLUMN_SIZE")));
			}
			
		}
		
		
		@Override
		public String toString() {
			return String.format("TABLE %s (%s)",name,StringHelper.join(columns, ","));
		}
		
		public class Column {
			private String name;
			private String sqltype;
			private Integer size;
			
			public Column(String name,String sqltype,Integer size) {
				this.name = name;
				this.sqltype = sqltype;
				this.size = size;
			}
			
			public String getName() {
				return name;
			}
			public void setName(String name) {
				this.name = name;
			}
			
			public String getSqltype() {
				return sqltype;
			}
			public void setSqltype(String sqltype) {
				this.sqltype = sqltype;
			}
			
			public Integer getSize() {
				return size;
			}
			public void setSize(Integer size) {
				this.size = size;
			}
			
			@Override
			public String toString() {
				if (!size.equals(0)){
					return String.format("%s %s(%d)", name, sqltype, size);
				} else {
					return String.format("%s %s", name, sqltype);
				}
			}
		}
		
	}
	
}