package com.fasterxml.jackson.dataformat.avro;

import java.io.IOException;
import java.io.OutputStream;
import java.math.BigDecimal;
import java.math.BigInteger;
import java.nio.ByteBuffer;

import org.apache.avro.io.BinaryEncoder;

import com.fasterxml.jackson.core.*;
import com.fasterxml.jackson.core.base.GeneratorBase;
import com.fasterxml.jackson.core.io.IOContext;
import com.fasterxml.jackson.dataformat.avro.apacheimpl.ApacheCodecRecycler;
import com.fasterxml.jackson.dataformat.avro.ser.AvroWriteContext;
import com.fasterxml.jackson.dataformat.avro.ser.EncodedDatum;

public class AvroGenerator extends GeneratorBase
{
    
Enumeration that defines all togglable features for Avro generators
/**
     * Enumeration that defines all togglable features for Avro generators
     */
    public enum Feature
        implements FormatFeature // since 2.7
    {
        
Feature that can be disabled to prevent Avro from buffering any more
data then absolutely necessary.
This affects buffering by underlying codec.
Note that disabling buffer is likely to reduce performance if the underlying
input/output is unbuffered.

Enabled by default to preserve the existing behavior.
Since:
2.7/**
         * Feature that can be disabled to prevent Avro from buffering any more
         * data then absolutely necessary.
         * This affects buffering by underlying codec.
         * Note that disabling buffer is likely to reduce performance if the underlying
         * input/output is unbuffered.
         *<p>
         * Enabled by default to preserve the existing behavior.
         *
         * @since 2.7
         */
        AVRO_BUFFERING(true),

        
Feature that tells Avro to write data in file format (i.e. including the schema with the data)
rather than the RPC format which is otherwise default

NOTE: reader-side will have to be aware of distinction as well, since possible inclusion
of this header is not 100% reliably auto-detectable (while header has distinct marker,
"raw" Avro content has no limitations and could theoretically have same pre-amble from data).
Since:
2.9/**
         * Feature that tells Avro to write data in file format (i.e. including the schema with the data)
         * rather than the RPC format which is otherwise default
         *<p>
         * NOTE: reader-side will have to be aware of distinction as well, since possible inclusion
         * of this header is not 100% reliably auto-detectable (while header has distinct marker,
         * "raw" Avro content has no limitations and could theoretically have same pre-amble from data).
         *
         * @since 2.9
         */
        AVRO_FILE_OUTPUT(false)
        ;

        protected final boolean _defaultState;
        protected final int _mask;
        
        
Method that calculates bit set (flags) of all features that
are enabled by default.
/**
         * Method that calculates bit set (flags) of all features that
         * are enabled by default.
         */
        public static int collectDefaults()
        {
            int flags = 0;
            for (Feature f : values()) {
                if (f.enabledByDefault()) {
                    flags |= f.getMask();
                }
            }
            return flags;
        }
        
        private Feature(boolean defaultState) {
            _defaultState = defaultState;
            _mask = (1 << ordinal());
        }

        @Override
        public boolean enabledByDefault() { return _defaultState; }

        @Override
        public int getMask() { return _mask; }

        @Override
        public boolean enabledIn(int flags) { return (flags & _mask) != 0; }
    }
    
    /*
    /**********************************************************
    /* Configuration
    /**********************************************************
     */

    final protected IOContext _ioContext;

    
Bit flag composed of bits that indicate which Features are enabled. /**
     * Bit flag composed of bits that indicate which
     * {@link AvroGenerator.Feature}s
     * are enabled.
     */
    protected int _formatFeatures;

    protected AvroSchema _rootSchema;

    /*
    /**********************************************************
    /* Output state
    /**********************************************************
     */

    final protected OutputStream _output;

    
Reference to the root context since that is needed for serialization
/**
     * Reference to the root context since that is needed for serialization
     */
    protected AvroWriteContext _rootContext;

    
Current context
/**
     * Current context
     */
    protected AvroWriteContext _avroContext;

    
Lazily constructed encoder; reused in case of writing root-value sequences.
/**
     * Lazily constructed encoder; reused in case of writing root-value sequences.
     */
    protected BinaryEncoder _encoder;

    
Flag that is set when the whole content is complete, can
be output.
/**
     * Flag that is set when the whole content is complete, can
     * be output.
     */
    protected boolean _complete;

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

    public AvroGenerator(IOContext ctxt, int jsonFeatures, int avroFeatures,
            ObjectCodec codec, OutputStream output)
        throws IOException
    {
        super(jsonFeatures, codec);
        _ioContext = ctxt;
        _formatFeatures = avroFeatures;
        _output = output;
        _avroContext = AvroWriteContext.nullContext();
        _encoder = ApacheCodecRecycler.encoder(_output, isEnabled(Feature.AVRO_BUFFERING));
    }

    public void setSchema(AvroSchema schema)
    {
        if (_rootSchema == schema) {
            return;
        }
        _rootSchema = schema;
        // start with temporary root...
        _avroContext = _rootContext = AvroWriteContext.createRootContext(this,
                schema.getAvroSchema(), _encoder);
    }

    /*                                                                                       
    /**********************************************************                              
    /* Versioned                                                                             
    /**********************************************************                              
     */

    @Override
    public Version version() {
        return PackageVersion.VERSION;
    }

    /*
    /**********************************************************
    /* Overridden methods, configuration
    /**********************************************************
     */

    
Not sure what to do here; could reset indentation to some value maybe?
/**
     * Not sure what to do here; could reset indentation to some value maybe?
     */
    @Override
    public AvroGenerator useDefaultPrettyPrinter()
    {
        return this;
    }

    
Not relevant, as binary formats typically have no indentation.
/**
     * Not relevant, as binary formats typically have no indentation.
     */
    @Override
    public AvroGenerator setPrettyPrinter(PrettyPrinter pp) {
        return this;
    }

    @Override
    public Object getOutputTarget() {
        return _output;
    }

    
Unfortunately we have no visibility into buffering Avro codec does;
and need to return -1 to reflect that lack of knowledge.
/**
     * Unfortunately we have no visibility into buffering Avro codec does;
     * and need to return <code>-1</code> to reflect that lack of knowledge.
     */
    @Override
    public int getOutputBuffered() {
        return -1;
    }

    @Override public AvroSchema getSchema() {
        return _rootSchema;
    }

    @Override
    public void setSchema(FormatSchema schema)
    {
        if (!(schema instanceof AvroSchema)) {
            throw new IllegalArgumentException("Can not use FormatSchema of type "
                    +schema.getClass().getName());
        }
        setSchema((AvroSchema) schema);
    }

    /*
    /**********************************************************
    /* Public API, capability introspection methods
    /**********************************************************
     */

    @Override
    public boolean canUseSchema(FormatSchema schema) {
        return (schema instanceof AvroSchema);
    }

    // 10-Sep-2019, Tatu: Should implement wrt [dataformats-binary#179], but...
    //    can't. Not yet, will just break things. Wait until 2.11
//    @Override
//    public boolean canWriteBinaryNatively() { return true; }

    /*
    /**********************************************************
    /* Extended API, configuration
    /**********************************************************
     */

    public AvroGenerator enable(Feature f) {
        _formatFeatures |= f.getMask();
        return this;
    }

    public AvroGenerator disable(Feature f) {
        _formatFeatures &= ~f.getMask();
        return this;
    }

    public final boolean isEnabled(Feature f) {
        return (_formatFeatures & f.getMask()) != 0;
    }

    public AvroGenerator configure(Feature f, boolean state) {
        if (state) {
            enable(f);
        } else {
            disable(f);
        }
        return this;
    }

    @Override
    public JsonGenerator overrideFormatFeatures(int values, int mask) {
        int oldF = _formatFeatures;
        int newF = (_formatFeatures & ~mask) | (values & mask);

        if (oldF != newF) {
            _formatFeatures = newF;
            // 22-Oct-2015, tatu: Actually, not way to change buffering details at
            //   this point. If change needs to be dynamic have to change it
        }
        return this;
    }

    /*
    /**********************************************************************
    /* Overridden methods; writing field names
    /**********************************************************************
     */
    
    /* And then methods overridden to make final, streamline some
     * aspects...
     */

    @Override
    public final void writeFieldName(String name) throws IOException
    {
        _avroContext.writeFieldName(name);
    }

    @Override
    public final void writeFieldName(SerializableString name)
        throws IOException
    {
        _avroContext.writeFieldName(name.getValue());
    }

    @Override
    public final void writeStringField(String fieldName, String value)
        throws IOException
    {
        _avroContext.writeFieldName(fieldName);
        writeString(value);
    }

    /*
    /**********************************************************
    /* Public API: low-level I/O
    /**********************************************************
     */

    @Override
    public final void flush() throws IOException {
        if (isEnabled(JsonGenerator.Feature.FLUSH_PASSED_TO_STREAM)) {
            _output.flush();
        }
    }

    @Override
    public void close() throws IOException
    {
        super.close();
        if (isEnabled(JsonGenerator.Feature.AUTO_CLOSE_JSON_CONTENT)) {
            AvroWriteContext ctxt;
            while ((ctxt = _avroContext) != null) {
                if (ctxt.inArray()) {
                    writeEndArray();
                } else if (ctxt.inObject()) {
                    writeEndObject();
                } else {
                    break;
                }
            }
        }
        // May need to finalize...
        /* 18-Nov-2014, tatu: Since this method is (a) often called as a result of an exception,
         *   and (b) quite likely to cause an exception of its own, need to work around
         *   combination of problems; one part being to catch non-IOExceptions; something that
         *   is usually NOT done. Partly this is because Avro codec is leaking low-level exceptions
         *   such as NPE.
         */
        if (!_complete) {
            try {
                _complete();
            } catch (IOException e) {
                throw e;
            } catch (Exception e) {
                throw new JsonGenerationException("Failed to close AvroGenerator: ("
                        +e.getClass().getName()+"): "+e.getMessage(), e, this);
            }
        }
        if (_output != null) {
            if (_ioContext.isResourceManaged() || isEnabled(JsonGenerator.Feature.AUTO_CLOSE_TARGET)) {
                _output.close();
            } else  if (isEnabled(JsonGenerator.Feature.FLUSH_PASSED_TO_STREAM)) {
                // If we can't close it, we should at least flush
                _output.flush();
            }
        }
        // Internal buffer(s) generator has can now be released as well
        _releaseBuffers();
    }

    /*
    /**********************************************************
    /* Public API: structural output
    /**********************************************************
     */

    @Override
    public final void writeStartArray() throws IOException {
        _avroContext = _avroContext.createChildArrayContext(null);
        _complete = false;
    }

    @Override
    public final void writeEndArray() throws IOException
    {
        if (!_avroContext.inArray()) {
            _reportError("Current context not Array but "+_avroContext.typeDesc());
        }
        _avroContext = _avroContext.getParent();
        if (_avroContext.inRoot() && !_complete) {
            _complete();
        }
    }

    @Override
    public final void writeStartObject() throws IOException {
        _avroContext = _avroContext.createChildObjectContext(null);
        _complete = false;
    }

    @Override
    public void writeStartObject(Object forValue) throws IOException {
        _avroContext = _avroContext.createChildObjectContext(forValue);
        _complete = false;
    }

    @Override
    public final void writeEndObject() throws IOException
    {
        if (!_avroContext.inObject()) {
            _reportError("Current context not Object but "+_avroContext.typeDesc());
        }
        if (!_avroContext.canClose()) {
            _reportError("Can not write END_OBJECT after writing FIELD_NAME but not value");
        }
        _avroContext = _avroContext.getParent();

        if (_avroContext.inRoot() && !_complete) {
            _complete();
        }
    }

    /*
    /**********************************************************
    /* Output method implementations, textual
    /**********************************************************
     */

    @Override
    public void writeString(String text) throws IOException
    {
        if (text == null) {
            writeNull();
            return;
        }
        _avroContext.writeString(text);
    }

    @Override
    public void writeString(char[] text, int offset, int len) throws IOException {
        writeString(new String(text, offset, len));
    }

    @Override
    public final void writeString(SerializableString sstr) throws IOException {
        writeString(sstr.toString());
    }

    @Override
    public void writeRawUTF8String(byte[] text, int offset, int len) throws IOException {
        _reportUnsupportedOperation();
    }

    @Override
    public final void writeUTF8String(byte[] text, int offset, int len) throws IOException {
        writeString(new String(text, offset, len, "UTF-8"));
    }

    /*
    /**********************************************************
    /* Output method implementations, unprocessed ("raw")
    /**********************************************************
     */

    @Override
    public void writeEmbeddedObject(Object object) throws IOException {
        if (object instanceof EncodedDatum) {
            _avroContext.writeValue(object);
            return;
        }
        super.writeEmbeddedObject(object);
    }

    @Override
    public void writeRaw(String text) throws IOException {
        _reportUnsupportedOperation();
    }

    @Override
    public void writeRaw(String text, int offset, int len) throws IOException {
        _reportUnsupportedOperation();
    }

    @Override
    public void writeRaw(char[] text, int offset, int len) throws IOException {
        _reportUnsupportedOperation();
    }

    @Override
    public void writeRaw(char c) throws IOException {
        _reportUnsupportedOperation();
    }

    @Override
    public void writeRawValue(String text) throws IOException {
        _reportUnsupportedOperation();
    }

    @Override
    public void writeRawValue(String text, int offset, int len) throws IOException {
        _reportUnsupportedOperation();
    }

    @Override
    public void writeRawValue(char[] text, int offset, int len) throws IOException {
        _reportUnsupportedOperation();
    }

    /*
    /**********************************************************
    /* Output method implementations, base64-encoded binary
    /**********************************************************
     */
    
    @Override
    public void writeBinary(Base64Variant b64variant, byte[] data, int offset, int len) throws IOException
    {
        if (data == null) {
            writeNull();
            return;
        }
        _avroContext.writeValue(ByteBuffer.wrap(data, offset, len));
    }

    /*
    /**********************************************************
    /* Output method implementations, primitive
    /**********************************************************
     */

    @Override
    public void writeBoolean(boolean state) throws IOException {
        _avroContext.writeValue(state ? Boolean.TRUE : Boolean.FALSE);
    }

    @Override
    public void writeNull() throws IOException {
        _avroContext.writeNull();
    }

    @Override
    public void writeNumber(int i) throws IOException {
        _avroContext.writeValue(Integer.valueOf(i));
    }

    @Override
    public void writeNumber(long l) throws IOException {
        _avroContext.writeValue(Long.valueOf(l));
    }

    @Override
    public void writeNumber(BigInteger v) throws IOException
    {
        if (v == null) {
            writeNull();
            return;
        }
        _avroContext.writeValue(v);
    }
    
    @Override
    public void writeNumber(double d) throws IOException {
        _avroContext.writeValue(Double.valueOf(d));
    }    

    @Override
    public void writeNumber(float f) throws IOException {
        _avroContext.writeValue(Float.valueOf(f));
    }

    @Override
    public void writeNumber(BigDecimal dec) throws IOException
    {
        if (dec == null) {
            writeNull();
            return;
        }
        _avroContext.writeValue(dec);
    }

    @Override
    public void writeNumber(String encodedValue) throws IOException {
        /* 08-Mar-2016, tatu: Looks like this may need to be supported, eventually,
         *   for things like floating-point (Decimal) types. But, for now,
         *   let's at least handle null.
         */
        if (encodedValue == null) {
            writeNull();
            return;
        }
        throw new UnsupportedOperationException("Can not write 'untyped' numbers");
    }

    /*
    /**********************************************************
    /* Implementations for methods from base class
    /**********************************************************
     */
    
    @Override
    protected final void _verifyValueWrite(String typeMsg) throws IOException {
        _throwInternal();
    }

    @Override
    protected void _releaseBuffers() {
        // no super implementation to call
        BinaryEncoder e = _encoder;
        if (e != null) {
            _encoder = null;
            ApacheCodecRecycler.release(e);
        }
    }

    /*
    /**********************************************************
    /* Helper methods
    /**********************************************************
     */

    protected void _complete() throws IOException
    {
        _complete = true;

        // add defensive coding here but only because this often gets triggered due
        // to forced closure resulting from another exception; so, we typically
        // do not want to hide the original problem...
        // First one sanity check, for a (relatively?) common case
        if (_rootContext != null) {
            _rootContext.complete();
        }
    }
}