import streamlit as st
import pandas as pd
from pathlib import Path
import requests
import base64
from requests.auth import HTTPBasicAuth
import torch

st.set_page_config(layout="wide")

@st.cache(allow_output_mutation=True)
def load_model():
    from transformers import (
        EncoderDecoderModel,
        AutoTokenizer
    )
    PRETRAINED = "raynardj/wenyanwen-ancient-translate-to-modern"
    tokenizer = AutoTokenizer.from_pretrained(PRETRAINED)
    model = EncoderDecoderModel.from_pretrained(PRETRAINED)
    return tokenizer, model


tokenizer, model = load_model()


def inference(text):
    print(f"from: {text}")
    tk_kwargs = dict(
        truncation=True,
        max_length=168,
        padding="max_length",
        return_tensors='pt')

    inputs = tokenizer([text, ], **tk_kwargs)
    with torch.no_grad():
        new = tokenizer.batch_decode(
            model.generate(
                inputs.input_ids,
                attention_mask=inputs.attention_mask,
                num_beams=3,
                max_length=256,
                bos_token_id=101,
                eos_token_id=tokenizer.sep_token_id,
                pad_token_id=tokenizer.pad_token_id,
            ), skip_special_tokens=True)[0].replace(" ", "")
    print(f"to: {new}")
    return new


@st.cache
def get_file_df():
    file_df = pd.read_csv("meta.csv")
    return file_df


file_df = get_file_df()

st.sidebar.title("【隨無涯】")
st.sidebar.markdown("""
* 朕自庖[🤗 模型](https://huggingface.co/raynardj/wenyanwen-ancient-translate-to-modern), [⭐️ 訓習處](https://github.com/raynardj/yuan)
* 📚 充棟汗牛，取自[殆知閣](http://www.daizhige.org/)，[github api](https://github.com/garychowcmu/daizhigev20)
""")

c2 = st.container()
c2.write("The entirety of ancient Chinese literature, with a modern translator at your side.")
st.markdown("""---""")
c = st.container()

USER_ID = st.secrets["USER_ID"]
SECRET = st.secrets["SECRET"]


@st.cache
def get_maps():
    file_obj_hash_map = dict(file_df[["filepath", "obj_hash"]].values)
    file_size_map = dict(file_df[["filepath", "fsize"]].values)
    return file_obj_hash_map, file_size_map


file_obj_hash_map, file_size_map = get_maps()


def show_file_size(size: int):
    if size < 1024:
        return f"{size} B"
    elif size < 1024*1024:
        return f"{size//1024} KB"
    else:
        return f"{size/1024//1024} MB"

@st.cache(max_entries=100, allow_output_mutation=True)
def fetch_file(path):
    # reading from local path first
    if (Path("data")/path).exists():
        with open(Path("data")/path, "r") as f:
            return f.read()

    # read from github api
    obj_hash = file_obj_hash_map[path]
    auth = HTTPBasicAuth(USER_ID, SECRET)
    url = f"https://api.github.com/repos/garychowcmu/daizhigev20/git/blobs/{obj_hash}"
    print(f"requesting {url}")
    r = requests.get(url, auth=auth)
    if r.status_code == 200:
        data = r.json()
        content = base64.b64decode(data['content']).decode('utf-8')
        return content
    else:
        r.raise_for_status()


@st.cache(allow_output_mutation=True, max_entries=100)
def fetch_from_df(sub_paths: str = ""):
    sub_df = file_df.copy()
    for idx, step in enumerate(sub_paths):
        sub_df.query(f"col_{idx} == '{step}'", inplace=True)
        if len(sub_df) == 0:
            return None
    return list(sub_df[f"col_{len(sub_paths)}"].unique())

def show_filepath(filepath: str):
    text = fetch_file(filepath)
    c.markdown(
            f"""<pre style='white-space:pre-wrap;max-height:300px;overflow-y:auto'>{text}</pre>""", unsafe_allow_html=True)

if st.sidebar.selectbox(label="何以尋跡 How to search",options=["以類尋書 category","書名求書 search"])=="以類尋書 category":

    # root_data = fetch_from_github()
    if 'pathway' in st.session_state:
        pass
    else:
        st.session_state.pathway = []

    path_text = st.sidebar.text("/".join(st.session_state.pathway))


    def reset_path():
        st.session_state.pathway = []
        path_text.text(st.session_state.pathway)


    if st.sidebar.button("還至初錄(back to root)"):
        reset_path()

    def display_tree():
        sublist = fetch_from_df(st.session_state.pathway)
        dropdown = st.sidebar.selectbox("【擇書 choose】", options=sublist)
        with st.spinner("書非借不能讀也..."):
            st.session_state.pathway.append(dropdown)
            if dropdown.endswith('.txt'):
                filepath = "/".join(st.session_state.pathway)
                file_size = file_size_map[filepath]
                with st.spinner(f"Load 載文:{filepath},({show_file_size(file_size)})"):
                    # if file size is too large, we will not load it
                    if file_size > 3*1024*1024:
                        print(f"skip {filepath}")
                        urlpath = filepath.replace(".txt", ".html")
                        dzg = f"http://www.daizhige.org/{urlpath}"
                        st.markdown(f"File too big 其文碩而難載，不能為之，[往 殆知閣]({dzg}), 或擇他書")
                        reset_path()
                        return None
                    path_text.text(filepath)
                    print(f"read {filepath}")
                    text = fetch_file(filepath)
                    # create markdown with max heights
                    c.markdown(
                        f"""<pre style='white-space:pre-wrap;max-height:300px;overflow-y:auto'>{text}</pre>""", unsafe_allow_html=True
                        )
                    reset_path()

            else:
                sub_list = fetch_from_df(
                    st.session_state.pathway)
                path_text.text("/".join(st.session_state.pathway))
                display_tree()

    display_tree()
else:
    def search_kw():
        result = file_df[file_df.filepath.str.contains(st.session_state.kw)].reset_index(drop=True)
        if len(result) == 0:
            st.sidebar.write(f"尋之不得:{st.session_state.kw}")
        else:
            filepath = st.sidebar.selectbox("選一書名", options=list(result.head(15).filepath))
            show_filepath(filepath)

    def loading_with_search():
        kw = st.sidebar.text_input("書名求書 Search", value="楞伽经")
        st.session_state.kw = kw
        search_kw()

    loading_with_search()


def translate_text():
    if c2.button("【曉文達義 Translate】"):
        if cc:
            if len(cc) > 168:
                c2.write(f"句甚長 不得過百又六十八字 Sentence too long, should be less than 168 characters")
            else:
                c2.markdown(f"""```{inference(cc)}```""")
        else:
            c2.write("【入難曉之文字 Please input sentence for translating】")

cc = c2.text_area("【入難曉之文字 Input sentence】", height=150)
translate_text()