package gudusoft.gsqlparser.dlineage.dataflow.model;

import gudusoft.gsqlparser.ESqlClause;
import gudusoft.gsqlparser.TSourceToken;
import gudusoft.gsqlparser.dlineage.util.Pair3;
import gudusoft.gsqlparser.nodes.TObjectName;
import gudusoft.gsqlparser.nodes.TParseTreeNode;
import gudusoft.gsqlparser.util.SQLUtil;

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

public class TableColumnRelationshipElement implements RelationshipElement<TableColumn> {

    private TableColumn column;

    private String tableAlias;

    private Integer columnIndex;

    private ESqlClause relationLocation;

    // Where THIS relation referenced the column (e.g. the operand in an ON or
    // WHERE clause). The wrapped TableColumn is shared between the definition
    // site and every reference, so its own position cannot carry the
    // per-reference coordinate. Null when the reference site is unknown or has
    // no real source token. Deliberately excluded from equals/hashCode.
    private Pair3<Long, Long, String> referenceStartPosition;

    private Pair3<Long, Long, String> referenceEndPosition;

    private List<Transform> transforms = new ArrayList<Transform>();

    public TableColumnRelationshipElement(TableColumn column) {
        this.column = column;
        if (column.getColumnObject() != null && column.getColumnObject().getTableString() != null) {
            if (column.getTable().getAliasList().contains(column.getColumnObject().getTableString())) {
                this.tableAlias = column.getColumnObject().getTableString();
            } else {
                this.tableAlias = column.getTable().getCurrentAlias();
            }
        } else {
            this.tableAlias = column.getTable().getCurrentAlias();
        }
    }

    public TableColumnRelationshipElement(TableColumn column, int index) {
        this.column = column;
        this.columnIndex = index;
        if (column.getColumnObject().getTableString() != null) {
            if (column.getTable().getAliasList().contains(column.getColumnObject().getTableString())) {
                this.tableAlias = column.getColumnObject().getTableString();
            } else {
                this.tableAlias = column.getTable().getCurrentAlias();
            }
        } else {
            this.tableAlias = column.getTable().getCurrentAlias();
        }
    }

    public TableColumnRelationshipElement(TableColumn column,
                                          ESqlClause relationLocation) {
        this.column = column;
        this.relationLocation = relationLocation;
        if (column.getColumnObject() != null && column.getColumnObject().getTableString() != null) {
            if (column.getTable().getAliasList().contains(column.getColumnObject().getTableString())) {
                this.tableAlias = column.getColumnObject().getTableString();
            } else {
                this.tableAlias = column.getTable().getCurrentAlias();
            }
        } else {
            this.tableAlias = column.getTable().getCurrentAlias();
        }
    }

    public TableColumnRelationshipElement(TableColumn column, ESqlClause relationLocation,
                                          TObjectName referenceObject) {
        this(column, relationLocation);
        setReferencePosition(referenceObject);
    }

    /**
     * Records the span of the object name this relation was built from, so the
     * serialized source can point at the reference site (the ON/WHERE operand)
     * instead of the shared column model's definition site. Ignores synthesized
     * object names, which have no real source token (their tokens sit at
     * line 1, column 1).
     */
    public void setReferencePosition(TObjectName referenceObject) {
        if (referenceObject == null || referenceObject.getStartToken() == null
                || referenceObject.getEndToken() == null) {
            return;
        }
        TSourceToken startToken = referenceObject.getStartToken();
        TSourceToken endToken = referenceObject.getEndToken();
        if (startToken.lineNo <= 0 || (startToken.lineNo == 1 && startToken.columnNo == 1)) {
            return;
        }
        this.referenceStartPosition = new Pair3<Long, Long, String>(startToken.lineNo, startToken.columnNo,
                ModelBindingManager.getGlobalHash());
        this.referenceEndPosition = new Pair3<Long, Long, String>(endToken.lineNo,
                endToken.columnNo + SQLUtil.endTrim(endToken.getAstext()).length(),
                ModelBindingManager.getGlobalHash());
    }

    public Pair3<Long, Long, String> getReferenceStartPosition() {
        return referenceStartPosition;
    }

    public Pair3<Long, Long, String> getReferenceEndPosition() {
        return referenceEndPosition;
    }

    @Override
    public TableColumn getElement() {
        return column;
    }

    public ESqlClause getRelationLocation() {
        return relationLocation;
    }

    @Override
    public int hashCode() {
        final int prime = 31;
        int result = 1;
        result = prime
                * result
                + ((column == null) ? 0 : column.hashCode());
        result = prime
                * result
                + ((relationLocation == null) ? 0
                : relationLocation.hashCode());
        return result;
    }

    @Override
    public boolean equals(Object obj) {
        if (this == obj)
            return true;
        if (obj == null)
            return false;
        if (getClass() != obj.getClass())
            return false;
        TableColumnRelationshipElement other = (TableColumnRelationshipElement) obj;
        if (column == null) {
            if (other.column != null)
                return false;
        } else if (!column.equals(other.column))
            return false;
        if (relationLocation != other.relationLocation)
            return false;
        return true;
    }

    public Integer getColumnIndex() {
        return columnIndex;
    }

    @Override
    public List<Transform> getTransforms() {
        return transforms;
    }

    public void addTransform(String type, TParseTreeNode code) {
        if (ModelBindingManager.getGlobalOption() != null && !ModelBindingManager.getGlobalOption().isTransform()) {
            return;
        }
        Transform transform = new Transform();
        transform.setType(type);
        transform.setCode(code);
        transforms.add(transform);
    }

    public String getTableAlias() {
        return tableAlias;
    }
}