import numpy as np
import pandas as pd
import streamlit as st
import json

st.set_page_config(layout="wide")

# load data
f = open('data.json')
recipes_json = json.load(f)
recipes = pd.DataFrame(recipes_json)
ingredients = pd.DataFrame(recipes_json).explode('ingredients')
bar_list = ingredients.loc[ingredients['ingredients'].notnull(), 'ingredients'].unique().tolist()
bar_dict = []
for item in bar_list:
    item_dict = {}
    item_dict['ingredients'] = item
    item_dict['have'] = False
    bar_dict.append(item_dict)
    
bar_df = pd.DataFrame(bar_dict)
def similarity(ratings, kind='user', epsilon=1e-9):
        if kind == 'user':
            sim = ratings.dot(ratings.T) + epsilon
        elif kind == 'item':
            sim = ratings.T.dot(ratings) + epsilon
        norms = np.array([np.sqrt(np.diagonal(sim))])
        return (sim / norms / norms.T)
pivot = ingredients[['name', 'ingredients']].copy()
pivot['count'] = 1
pivot = pivot.set_index(['name', 'ingredients'])['count'].unstack().reset_index()
pivot.rename_axis(None, axis=1, inplace=True)
pivot.fillna(0, inplace=True)
pivot_names = pivot.columns
pivot_np = np.array(pivot.set_index('name'))
recipe_similarity = pd.DataFrame(similarity(pivot_np, kind='user'))
recipe_similarity.columns = pivot['name'].values
recipe_similarity.index = pivot['name'].values

# manage session state
if 'filter_bar' not in st.session_state:
    st.session_state.filter_bar = recipes['name'].to_list()

if 'bar_df' not in st.session_state:
    st.session_state.bar_df = bar_df
    st.session_state.bar_df_edited = st.session_state.bar_df.copy() 

# recipe finder section
st.header("Recipe Finder")
with st.expander("Find recipes by name, ingredients, and type"):
    # name search
    name_search = st.text_input('Search recipes by name')
    if name_search == "":
        filter_name = recipes['name'].to_list()
    else:
        filter_1 = recipes['name'].str.contains(name_search.lower())
        filter_name = recipes.loc[filter_1, 'name'].to_list()
    
    # ingredient filter
    options = st.multiselect(
        'Select ingredients to filter by:',ingredients['ingredients'].unique())
    filter_type = st.radio(
        "Specify type of ingredient filtering:",
        [
            'Recipe contains ANY of the specified ingredients', 
            'Recipe contains ALL of the specified ingredients'
        ]
    )
    if len(options)==0:
        filter_ingredient = recipes['name'].to_list()
    else:
        if filter_type == 'Recipe contains ANY of the specified ingredients':
            filter_1 = ingredients['ingredients'].isin(options)
            filter_ingredient = ingredients.loc[filter_1, 'name'].to_list()
        elif filter_type == 'Recipe contains ALL of the specified ingredients':
            filter_1 = ingredients['ingredients'].isin(options)
            ingredients['has_ingredient'] = 0
            ingredients.loc[filter_1, 'has_ingredient'] = 1
            pivot = ingredients.groupby('name').agg(sum_has_ingredients=('has_ingredient', 'sum')).reset_index()
            filter_ingredient = pivot.loc[pivot['sum_has_ingredients']==len(options), 'name'].to_list()
    
    # source filter
    source_options = st.multiselect(
        'Filter by source:',recipes['source'].unique())      
    if len(source_options)==0:
        filter_source = recipes['name'].to_list()
    else:
        filter_1 = recipes['source'].isin(source_options)
        filter_source = recipes.loc[filter_1, 'name'].to_list()
    
    # type filter
    type_options = st.multiselect(
        'Filter by type:',recipes['recipe_type'].unique())      
    if len(type_options)==0:
        filter_type = recipes['name'].to_list()
    else:
        filter_1 = recipes['recipe_type'].isin(type_options)
        filter_type = recipes.loc[filter_1, 'name'].to_list()

with st.expander("Find recipes by what you can make with your bar at home"):
    # input home bar
    st.session_state.bar_df_edited = st.data_editor(st.session_state.bar_df, disabled=["ingredients"], hide_index=True)
    if st.session_state.bar_df_edited['have'].sum() == 0:
        st.session_state.filter_bar = recipes['name'].to_list()
    else:
        ingredients_joined = ingredients.join(st.session_state.bar_df_edited.set_index('ingredients'), on='ingredients')
        ingredients_joined.replace({'have': {True: 1, False: 0}}, inplace=True)
        pivot = ingredients_joined.groupby('name').agg(sum_needs_ingredients=('have', 'count'), sum_has_ingredients=('have', 'sum')).reset_index()
        filter_1 = (pivot['sum_has_ingredients'] > 0) & (pivot['sum_needs_ingredients'] > 0)
        filter_2 = pivot['sum_needs_ingredients'] == pivot['sum_has_ingredients']
        filter_all = filter_1 & filter_2
        st.session_state.filter_bar = pivot.loc[filter_all, 'name'].to_list()

with st.expander("Find recipes that are similar to one another"):
    similar_select = st.multiselect("Select a recipe:", recipes['name'], max_selections=1)

# Recipes section
st.header("Recipes")
filter_all = list(set(filter_name) & set(filter_ingredient) & set(filter_source) & set(filter_type) & set(st.session_state.filter_bar))

if len(similar_select) > 0:
    st.markdown(f'Recipes sorted with most similar to **{similar_select[0]}** at the top.')
    st.dataframe(
        recipes.set_index('name') \
        .join(recipe_similarity[similar_select], on='name') \
        .reset_index() \
        .sort_values(by=similar_select, ascending=False) \
        .query('name in @filter_all'),
        column_config={similar_select[0]: st.column_config.NumberColumn('% similarity to selected')},
        hide_index=True)
else:
    st.dataframe(recipes[recipes['name'].isin(filter_all)], hide_index=True)