import pandas as pd
import streamlit as st
from transformers import AutoModelForTokenClassification, AutoTokenizer, pipeline

from src import GBRT, wikipedia_search, wikidata_search

TYPE = {
    'LOC': ' location',
    'PER': ' person',
    'ORG': ' organization',
    'MISC': ''
}

COLOR = {
    'LOC': '#10B981',
    'PER': '#0EA5E9',
    'ORG': '#A855F7',
    'MISC': '#F97316'
}

# ---------------------------------------------------------------------------
# Loading models
# ---------------------------------------------------------------------------


@st.cache(allow_output_mutation=True, show_spinner=True)
def load_models():
    # NER
    tokenizer = AutoTokenizer.from_pretrained("dslim/bert-base-NER")
    bert_ner = AutoModelForTokenClassification.from_pretrained("dslim/bert-base-NER")
    tagger = pipeline("token-classification", model=bert_ner, tokenizer=tokenizer,
                      device=-1, aggregation_strategy="average")
    # NED
    model = GBRT()
    return model, tagger


# ---------------------------------------------------------------------------
# Page setup
# ---------------------------------------------------------------------------
st.set_page_config(layout="wide", page_title='Named Entity Disambiguation')
col1, col2 = st.columns(2)


# ---------------------------------------------------------------------------
# Candidate Generation
# ---------------------------------------------------------------------------
def get_candidates(mentions_tags):
    candidates = []
    cache = {}
    for mention, tag in mentions_tags:
        if (mention, tag) in cache.keys():
            candidates.append((mention, cache[(mention, tag)]))
        else:
            cands = wikidata_search(mention, limit=3)
            if cands == []:
                cands = wikipedia_search(mention, limit=3)
            cache[(mention, tag)] = cands
            candidates.append((mention, cands))
            print(mention, cands)
    return candidates


# ---------------------------------------------------------------------------
# Rendering Setup
# ---------------------------------------------------------------------------
def display_tag(text, typ, label):
    if label != 'NIL':
        return f'[<span style="color: {COLOR[typ]}" class="tag">**{text}** <small>{typ}</small></span>](https://en.wikipedia.org/wiki/{label})'
    else:
        return f'<span style="color: #EF4444" class="tag">**{text}** <small>{typ}</small></span>'


# ---------------------------------------------------------------------------
# Full Pipeline
# ---------------------------------------------------------------------------
def main(text):
    # text = text.replace('\n', ' ')
    ner_results = tagger(text)
    tagged, last_pos = '', 0

    with st.spinner('Generating Candidates'):
        mentions_cands = get_candidates([(res['word'], res['entity_group']) for res in ner_results])

    with st.spinner('Disambiguating Mentions'):
        preditions = model.link(mentions_cands, text)

    with st.spinner('Rendering Results'):
        for i, res in enumerate(ner_results):
            tag = display_tag(res['word'], res['entity_group'], preditions[i][1])
            tagged += text[last_pos:res['start']] + tag
            last_pos = res['end']
        tagged += text[last_pos:]

    with col2:
        st.write("### Disambiguated Text")
        st.markdown("<style>a {text-decoration: none;} small {color: inherit !important} .tag {border: 1px solid; border-radius: 5px; padding: 0px 3px; white-space: nowrap}</style>", unsafe_allow_html=True)
        st.write(tagged, unsafe_allow_html=True)

    df = pd.DataFrame(data=preditions, columns=['Mention', 'Prediction', 'Confidence'])
    st.write("**Additional Information**")
    st.markdown("<style>tbody th {display:none} .blank {display:none}</style>", unsafe_allow_html=True)
    st.table(df)


if __name__ == '__main__': 
    model, tagger = load_models()
    with col1:
        st.write("### Input Text")
        user_input = st.text_area('Press Ctrl + Enter to update results',
                                  'George Washington went to Washington.', height=350)
        if user_input:
            main(user_input)