"
version 0.4
Word and Positional embedding module
"
module WPembeddings

using Embeddings
using JSON3
using Redis

include("Utils.jl")

export get_word_embedding, get_positional_embedding, wp_embedding


#----------------------------------------------------------------------------------------------
# user setting for word embedding
GloVe_embedding_filepath = "C:\\myWork\\my_projects\\AI\\NLP\\my_NLP\\glove.840B.300d.txt"
max_GloVe_vocab_size = 0  # size 10000+ or "all"
#----------------------------------------------------------------------------------------------






# load GloVe word embedding. URL of the embedding file: https://nlp.stanford.edu/projects/glove/
if max_GloVe_vocab_size == 0
    # don't load vocab
elseif max_GloVe_vocab_size != "all"
    @time const embtable = Embeddings.load_embeddings(GloVe{:en}, GloVe_embedding_filepath, 
                                    max_vocab_size=max_GloVe_vocab_size) # size 10000 or something
    const get_word_index = Dict(word=>ii for (ii,word) in enumerate(embtable.vocab))
else
    @time const embtable = Embeddings.load_embeddings(GloVe{:en}, GloVe_embedding_filepath)
    const get_word_index = Dict(word=>ii for (ii,word) in enumerate(embtable.vocab))
end


# if max_GloVe_vocab_size != "all"
#     @time const embtable = Embeddings.load_embeddings(GloVe{:en}, GloVe_embedding_filepath, 
#                                     max_vocab_size=max_GloVe_vocab_size) # size 10000 or something
#     const get_word_index = Dict(word=>ii for (ii,word) in enumerate(embtable.vocab))
# elseif max_GloVe_vocab_size == 0
# else
#     @time const embtable = Embeddings.load_embeddings(GloVe{:en}, GloVe_embedding_filepath)
#     const get_word_index = Dict(word=>ii for (ii,word) in enumerate(embtable.vocab))
# end


"""
    get_word_embedding(word::String)

Get embedding vector of a word. Its dimention is depend on GloVe file used

# Example

    we_matrix = get_word_embedding("blue")
"""
function get_word_embedding(word::String)
    index = get_word_index[word]
    embedding = embtable.embeddings[:,index]
    return embedding
end


"""
    get_positional_embedding(total_word_position::Integer, word_embedding_dimension::Integer=300)

return positional embedding matrix of size [word_embedding_dimension * total_word_position]

# Example

    pe_matrix = get_positional_embedding(length(content), 300)
"""
function get_positional_embedding(total_word_position::Integer, word_embedding_dimension::Integer=300)
    d = word_embedding_dimension
    p = total_word_position
    pe = [x = i%2 == 0 ? cos(j/(10^(2i/d))) : sin(j/(10^(2i/d))) for i = 1:d, j = 1:p]
    return pe

end


"""
    wp_embedding(tokenized_word::Array{String}, positional_embedding::Bool=false)

Word embedding with positional embedding.
tokenized_word = sentense's tokenized word (not sentense in English definition but BERT definition. 
                    1-BERT sentense can be 20+ English's sentense)

# Example

            
"""
function wp_embedding(tokenized_word::Array{String}, positional_embedding::Bool=false)
    we_matrix = 0
    for (i, v) in enumerate(tokenized_word)
        if i == 1
            we_matrix = get_word_embedding(v)
        else
            we_matrix = hcat(we_matrix, get_word_embedding(v))
        end
    end

    if positional_embedding
        pe_matrix = get_positional_embedding(length(tokenized_word), 300) # positional embedding
        wp_matrix = we_matrix + pe_matrix

        return wp_matrix
    else
        return we_matrix
    end
end


"""
    wp_query(tokenized_word::Array{String}, positional_embedding::Bool=false)

convert tokenized_word into JSON3 String to be sent to GloVe docker server
"""
function wp_query_send(tokenized_word::Array{String}, positional_embedding::Bool=false)
    d = Dict("tokenized_word"=> tokenized_word, "positional_embedding"=>positional_embedding)
    json3_str = JSON3.write(d)
    return json3_str
end


"""
    wp_query(tokenized_word::Array{String}, positional_embedding::Bool=false)

Using inside word_embedding_server to receive word embedding job
convert JSON3 String into tokenized_word and positional_embedding
"""
function wp_query_receive(json3_str::String)
    d = JSON3.read(json3_str)
    tokenized_word = Array(d.tokenized_word)
    positional_embedding = d.positional_embedding

    return tokenized_word, positional_embedding
end


"""
    Send tokenized_word to word_embedding_server and return word embedding

# Example

    WPembeddings.query_wp_server(tokenized_word)
"""
function query_wp_server(query;
                        host="0.0.0.0",
                        port=6379,
                        publish_channel="word_embedding_server/input",
                        positional_encoding=true)

    # channel used to receive JSON String from word_embedding_server
    wp_channel = Channel(10)
    function wp_receive(x)
        array = Utils.JSON3_str_to_Array(x)
        put!(wp_channel, array)
    end

    # establish connection to word_embedding_server using default port
    conn = Redis.RedisConnection(host=host, port=port)   
    sub = Redis.open_subscription(conn)
    Redis.subscribe(sub, "word_embedding_server/output", wp_receive)
    # Redis.subscribe(sub, "word_embedding_server/output", WPembeddings.wp_receive)

    # set positional_encoding = true to enable positional encoding
    query = WPembeddings.wp_query_send(query, positional_encoding) 
    # Ask word_embedding_server for word embedding
    Redis.publish(conn, publish_channel, query);
    wait(wp_channel)    # wait for word_embedding_server to response
    embedded_word = take!(wp_channel)

    disconnect(conn)
    return embedded_word  
end




















end