app.py

import flask
import dash
import dash_bootstrap_components as dbc
import os
import json
import tempfile
import time
import shutil

from dash import dcc, html, Input, Output, State

from src.md_json2sqlite import main

# Backend functions
from utils_analysis import visualise_bbox, copy_temp_imgs, analyze_imgs
from utils_ui import alert_msg

# Create temp folder for image upload
UPLOAD_FOLDER = tempfile.mkdtemp(dir=os.getcwd())

# Create a temp folder for storing the images with the bbox drawn
BBOX_FOLDER = tempfile.mkdtemp(dir=os.getcwd())

# Object to be returned
OUTPUT_OBJECT="detection_db.sqlite"

# Instructions as a list:
instr = [
    html.B("1. UPLOAD PICTURES: "), "Click on the Drag and Drop box below",
    html.B("2. ANALYZE: "), "Click 'Analyze'. You should see a spinner indicating that the images are being analyzed.",
    html.B("3. DOWNLOAD DATABASE: "), "Once the analysis is finished, click on the button 'Download' to get the results as an 'SQLite' database.",
    html.B("4. (optional) DOWNLOAD PICS WITH LABEL: "), "To download the processed images (i.e., displaying the bounding box) click on the button 'Download labelled pics'."
]

# Application 
app = dash.Dash(
    external_stylesheets=[dbc.themes.BOOTSTRAP]
)
app.title = 'MegaDetector Analysis Dashboard'

app.layout = html.Div([
    html.H1('MegaDetector Analysis Dashboard'),
    dbc.Alert(
        [
            html.Ul(
                id="instructions",
                children=[html.Li([html.B(instr[i]), instr[i+1]]) for i in range(0, len(instr), 2)],
                className="list-unstyled mb-0",
            )
        ],
        color="primary",
        className="mb-4",
    ),
    dcc.Upload(
        id='folder-upload',
        children=html.Div([
            'Drag and Drop or ',
            html.A('Select files')
        ]),
        style={
            'width': '50%',
            'height': '60px',
            'lineHeight': '60px',
            'borderWidth': '1px',
            'borderStyle': 'dashed',
            'borderRadius': '5px',
            'textAlign': 'center',
            'margin': '10px',
        },
        multiple=True
    ),
    html.Div(
        children=[
            html.Button('Analyze', id='analyze-button', n_clicks=0),
            dcc.Loading(id="loading", children=[html.Div(id='results-output')], type="circle", style={'marginTop': '80px'}), 
            html.Button('Download DB', id="download-button", n_clicks=0),
            html.Button('Download labelled pics', id='download-pics-button', n_clicks=0)
        ],
        style={'display': 'flex', 'justifyContent': 'center'}
    ),
    dcc.Download(id="download-db"),
    dcc.Download(id="download-pics"),

    # Add the error messages Div
    html.Div(id='info-msg', style={'justifyContent': 'center'}),
    html.Div(id='alert-message-bbox', style={'justifyContent': 'center'}),
    html.Div(id='alert-message-db', style={'justifyContent': 'center'}),
    html.Div(id='alert-msg-pics', style={'justifyContent': 'center'})
])

@app.callback(
    Output('results-output', 'children'),
    Output('alert-msg-pics', 'children'),
    Output('info-msg', 'children'),
    Input('analyze-button', 'n_clicks'),
    State('folder-upload', 'contents'),
    Input('folder-upload', 'filename'),
    State('info-msg', 'children'),
    State('alert-msg-pics', 'children')
)
def analyze_folder(n_clicks, contents, filenames, info_m, alert_pics):
    if not filenames or not contents:
        if n_clicks >= 1:
            alert_message = alert_msg("No images have been found, please upload some images")
            if alert_message and 'error-alert.dismissed' in dash.callback_context.triggered[0]['prop_id']:
                return None, html.Div(), html.Div()   # Dismiss the alert message
            return html.Div(), alert_message, html.Div() 
        else:
            return '', '', ''

    copy_temp_imgs(UPLOAD_FOLDER, filenames, contents)

    if n_clicks >= 1:
        
        info_m = analyze_imgs(UPLOAD_FOLDER, "list_of_detections.json", OUTPUT_OBJECT)

        if info_m and 'info-alert.dismissed' in dash.callback_context.triggered[0]['prop_id']:
            return None, html.Div(), html.Div()   # Dismiss the alert message

        return html.Div(), html.Div() , info_m
    
    return html.Div(), html.Div(), html.Div() 

@app.callback(
    Output('download-db', 'data'),
    Output('alert-message-db', 'children'),
    Input('download-button', 'n_clicks'),
    State('alert-message-db', 'children')  # Use State instead of Input for output-message
)
def dl_db(n_clicks, alert_message_db):
    if n_clicks>=1:
        if os.path.exists(OUTPUT_OBJECT):
            return dcc.send_file(OUTPUT_OBJECT), ''
        else:
            alert_message = alert_msg("Pictures have not been processed -> Database can not be found")

            if alert_message and 'error-alert.dismissed' in dash.callback_context.triggered[0]['prop_id']:
                return None, html.Div()  # Dismiss the alert message

            return None, alert_message
        
    return None, html.Div()
        
@app.callback(
        Output('download-pics', 'data'),
        Output('alert-message-bbox', 'children'),
        Input('download-pics-button', 'n_clicks'),
        State('alert-message-bbox', 'children')  # Use State instead of Input for output-message
)
def dl_bbox_pics(n_clicks, alert_message_bbox):
    if n_clicks>=1:
        if os.path.exists("list_of_detections.json"):
            visualise_bbox("list_of_detections.json", BBOX_FOLDER, UPLOAD_FOLDER)
            zip_filename = shutil.make_archive('processed_pics', 'zip', BBOX_FOLDER)
            return dcc.send_file(zip_filename), html.Div()
        else:
            alert_message = alert_msg("Pictures have not been processed -> Labelled pictures cannot be downloaded")

            if alert_message and 'error-alert.dismissed' in dash.callback_context.triggered[0]['prop_id']:
                return None, html.Div()  # Dismiss the alert message

            return None, alert_message
    return None, html.Div()
        
if __name__ == '__main__':
    app.run_server(host="0.0.0.0", port=8999, debug=True)