package com.fasterxml.jackson.dataformat.csv.impl;

import com.fasterxml.jackson.core.*;
import com.fasterxml.jackson.core.json.DupDetector;

Intermediate base context; for 2.x copied within CSV format codebase, in 3.0 will be part of jackson-core 
Since:
2.11/**
 * Intermediate base context; for 2.x copied within CSV format codebase,
 * in 3.0 will be part of {@code jackson-core}
 *
 * @since 2.11
 */
public final class SimpleTokenWriteContext extends JsonStreamContext
{
    
Parent context for this context; null for root context.
/**
     * Parent context for this context; null for root context.
     */
    protected final SimpleTokenWriteContext _parent;

    // // // Optional duplicate detection

    protected DupDetector _dups;

    /*
    /**********************************************************************
    /* Simple instance reuse slots; speed up things a bit (10-15%)
    /* for docs with lots of small arrays/objects
    /**********************************************************************
     */

    protected SimpleTokenWriteContext _childToRecycle;

    /*
    /**********************************************************************
    /* Location/state information (minus source reference)
    /**********************************************************************
     */

    
Name of the field of which value is to be written; only
used for OBJECT contexts
/**
     * Name of the field of which value is to be written; only
     * used for OBJECT contexts
     */
    protected String _currentName;

    protected Object _currentValue;

    
Marker used to indicate that we just wrote a field name
and now expect a value to write
/**
     * Marker used to indicate that we just wrote a field name
     * and now expect a value to write
     */
    protected boolean _gotFieldId;

    /*
    /**********************************************************************
    /* Life-cycle
    /**********************************************************************
     */

    protected SimpleTokenWriteContext(int type, SimpleTokenWriteContext parent, DupDetector dups,
            Object currentValue) {
        super();
        _type = type;
        _parent = parent;
        _dups = dups;
        _index = -1;
        _currentValue = currentValue;
    }

    private SimpleTokenWriteContext reset(int type, Object currentValue) {
        _type = type;
        _index = -1;
        _currentName = null;
        _gotFieldId = false;
        _currentValue = currentValue;
        if (_dups != null) { _dups.reset(); }
        return this;
    }

    public SimpleTokenWriteContext withDupDetector(DupDetector dups) {
        _dups = dups;
        return this;
    }

    @Override
    public Object getCurrentValue() {
        return _currentValue;
    }

    @Override
    public void setCurrentValue(Object v) {
        _currentValue = v;
    }

    /*
    /**********************************************************************
    /* Factory methods
    /**********************************************************************
     */

    public static SimpleTokenWriteContext createRootContext(DupDetector dd) {
        return new SimpleTokenWriteContext(TYPE_ROOT, null, dd, null);
    }

    public SimpleTokenWriteContext createChildArrayContext(Object currentValue) {
        SimpleTokenWriteContext ctxt = _childToRecycle;
        if (ctxt == null) {
            _childToRecycle = ctxt = new SimpleTokenWriteContext(TYPE_ARRAY, this,
                    (_dups == null) ? null : _dups.child(), currentValue);
            return ctxt;
        }
        return ctxt.reset(TYPE_ARRAY, currentValue);
    }

    public SimpleTokenWriteContext createChildObjectContext(Object currentValue) {
        SimpleTokenWriteContext ctxt = _childToRecycle;
        if (ctxt == null) {
            _childToRecycle = ctxt = new SimpleTokenWriteContext(TYPE_OBJECT, this,
                    (_dups == null) ? null : _dups.child(), currentValue);
            return ctxt;
        }
        return ctxt.reset(TYPE_OBJECT, currentValue);
    }

    /*
    /**********************************************************************
    /* Accessors
    /**********************************************************************
     */
    
    @Override public final SimpleTokenWriteContext getParent() { return _parent; }
    @Override public final String getCurrentName() {
        // 15-Aug-2019, tatu: Should NOT check this status because otherwise name
        //    in parent context is not accessible after new structured scope started
//        if (_gotFieldId) { ... }
        return _currentName;
    }

    @Override public boolean hasCurrentName() { return _gotFieldId; }

    
Method that can be used to both clear the accumulated references (specifically value set with setCurrentValue(Object)) that should not be retained, and returns parent (as would getParent() do). Typically called when closing the active context when encountering JsonToken.END_ARRAY or JsonToken.END_OBJECT. /**
     * Method that can be used to both clear the accumulated references
     * (specifically value set with {@link #setCurrentValue(Object)})
     * that should not be retained, and returns parent (as would
     * {@link #getParent()} do). Typically called when closing the active
     * context when encountering {@link JsonToken#END_ARRAY} or
     * {@link JsonToken#END_OBJECT}.
     */
    public SimpleTokenWriteContext clearAndGetParent() {
        _currentValue = null;
        // could also clear the current name, but seems cheap enough to leave?
        return _parent;
    }

    public DupDetector getDupDetector() {
        return _dups;
    }

    /*
    /**********************************************************************
    /* State changing
    /**********************************************************************
     */
    
    
Method that writer is to call before it writes a field name.
Returns:
Ok if name writing should proceed/**
     * Method that writer is to call before it writes a field name.
     *
     * @return Ok if name writing should proceed
     */
    public boolean writeFieldName(String name) throws JsonProcessingException {
        if ((_type != TYPE_OBJECT) || _gotFieldId) {
            return false;
        }
        _gotFieldId = true;
        _currentName = name;
        if (_dups != null) { _checkDup(_dups, name); }
        return true;
    }

    private final void _checkDup(DupDetector dd, String name) throws JsonProcessingException {
        if (dd.isDup(name)) {
            Object src = dd.getSource();
            throw new JsonGenerationException("Duplicate field '"+name+"'",
                    ((src instanceof JsonGenerator) ? ((JsonGenerator) src) : null));
        }
    }
    
    public boolean writeValue() {
        // Only limitation is with OBJECTs:
        if (_type == TYPE_OBJECT) {
            if (!_gotFieldId) {
                return false;
            }
            _gotFieldId = false;
        }
        ++_index;
        return true;
    }
}