package com.activequant.utils.snmp;

import java.util.ArrayList;
import java.util.List;

import org.snmp4j.agent.MOAccess;
import org.snmp4j.agent.mo.DefaultMOMutableRow2PC;
import org.snmp4j.agent.mo.DefaultMOTable;
import org.snmp4j.agent.mo.MOColumn;
import org.snmp4j.agent.mo.MOMutableTableModel;
import org.snmp4j.agent.mo.MOTable;
import org.snmp4j.agent.mo.MOTableIndex;
import org.snmp4j.agent.mo.MOTableSubIndex;
import org.snmp4j.smi.OID;
import org.snmp4j.smi.SMIConstants;
import org.snmp4j.smi.Variable;

/**
 * <p>
 * Utility class for adding dynamic data into an {@link MOTable}
 * </p>
 * 
 * 
 * <pre><code>
 MOTableBuilder builder = new MOTableBuilder(new OID(".1.3.6.1.2.1.2.2.1"))
	.addColumnType(SMIConstants.SYNTAX_INTEGER,MOAccessImpl.ACCESS_READ_ONLY)
	.addColumnType(SMIConstants.SYNTAX_OCTET_STRING,MOAccessImpl.ACCESS_READ_ONLY);
	for(MyObject o: myObjects) {	
		builder.addRowValue(new Integer32(o.getId()))
		.addRowValue(new OctetString(o.getName()));
	}
MOTable table = builder.build();
 </code>
 * 
 * <pre>
 * 
 * @author johanrask
 * 
 */
class MOTableBuilder {

    private MOTableSubIndex[] subIndexes = new MOTableSubIndex[] { new MOTableSubIndex(SMIConstants.SYNTAX_INTEGER) };
    private MOTableIndex indexDef = new MOTableIndex(subIndexes, false);

    private final List<MOColumn> columns = new ArrayList<MOColumn>();
    private final List<Variable[]> tableRows = new ArrayList<Variable[]>();
    private int currentRow = 0;
    private int currentCol = 0;

    private OID tableRootOid;

    private int colTypeCnt = 0;

    /**
     * Specified oid is the root oid of this table
     */
    MOTableBuilder(OID oid) {
        this.tableRootOid = oid;
    }

    /**
     * Adds all column types {@link MOColumn} to this table. Important to
     * understand that you must add all types here before adding any row values
     * 
     * @param syntax
     *            use {@link SMIConstants}
     * @param access
     * @return
     */
    public MOTableBuilder addColumnType(int syntax, MOAccess access) {
        colTypeCnt++;
        columns.add(new MOColumn(colTypeCnt, syntax, access));
        return this;
    }

    public MOTableBuilder addRowValue(Variable variable) {
        if (tableRows.size() == currentRow) {
            tableRows.add(new Variable[columns.size()]);
        }
        tableRows.get(currentRow)[currentCol] = variable;
        currentCol++;
        if (currentCol >= columns.size()) {
            currentRow++;
            currentCol = 0;
        }
        return this;
    }

    public MOTable build() {
        DefaultMOTable ifTable = new DefaultMOTable(tableRootOid, indexDef, columns.toArray(new MOColumn[0]));
        MOMutableTableModel model = (MOMutableTableModel) ifTable.getModel();
        int i = 1;

        for (Variable[] variables : tableRows) {
            model.addRow(new DefaultMOMutableRow2PC(new OID(String.valueOf(i)), variables));
            i++;
        }
        ifTable.setVolatile(true);
        return ifTable;
    }
}