tab4.py

import dash
from dash import dcc, html
from dash.dependencies import Input, Output, State
import sqlite3 as sql
from datetime import datetime
from server import app

# Fetch the last run number
def fetch_last_run():
    conn = sql.connect("labjackdb.db")
    c = conn.cursor()
    c.execute("SELECT * FROM run_number ORDER BY run_id DESC LIMIT 1")
    lastrun = (c.fetchone()[0]) - 1
    conn.close()
    return lastrun

# Fetch preferences
def fetch_preferences():
    conn = sql.connect("labjackdb.db")
    c = conn.cursor()
    c.execute("SELECT * FROM preferences")
    prefs = c.fetchone()
    conn.close()
    return prefs

# Fetch readings for a specific run
def fetch_readings(run_id):
    conn = sql.connect("labjackdb.db")
    c = conn.cursor()
    c.execute(f"SELECT * FROM dac_readings WHERE run_id = {run_id} ORDER BY time")
    readings = c.fetchall()
    conn.close()
    return readings

# Fetch run information
def fetch_run_info(run_id):
    conn = sql.connect("labjackdb.db")
    c = conn.cursor()
    c.execute(f"SELECT * FROM run_number WHERE run_id = {run_id}")
    run = c.fetchone()
    conn.close()
    return run

def tab4():
    lastrun = fetch_last_run()

    return html.Div([
        html.P('Enter filename'),
        html.Div(dcc.Input(id='input_filename', value='data.csv', type='text')),
        html.Div(id='filename_output'),
        
        html.P(f'Enter run to export, last run was: {lastrun}'),
        html.Div(dcc.Input(id='input_run', value=0, type='number', debounce=True)),
        html.Div('Run: ', id='data_output'),
        
        html.Button('Save', id='button', value='n_clicks'),
        html.Div(id='button_output', style={'display': 'none'}),
    ], style={'padding': '50px', 'textAlign': 'center'})

@app.callback(
    Output('data_output', 'children'),
    Output('filename_output', 'children'),
    Output('button_output', 'children'),
    Input('button', 'n_clicks'),
    State('input_run', 'value'),
    State('input_filename', 'value')
)
def exportcsv(n_clicks, run_id, path):
    if run_id <= 0:
        return 'Invalid run ID', '', n_clicks

    run_info = fetch_run_info(run_id)
    prefs = fetch_preferences()
    readings = fetch_readings(run_id)
    
    header_names = ['run', 'time', prefs[12], prefs[13], prefs[14], prefs[15], prefs[16]]
    header = ','.join(header_names) + '\n'

    with open(path, 'w') as fd:
        fd.write(header)
        for reading in readings:
            row = ','.join(map(str, reading[:8])) + '\n'
            fd.write(row)

    return f'Run: {run_id}', f'Filename: {path}', n_clicks