var { Client } = require('pg');
var express = require("express");
const path = require("path");
var cors = require('cors')
var app = express();
const port = 3000;

app.use(cors())

const static_path = path.join(__dirname, "public"); // The path to a public folder.

app.use(express.static(static_path));
app.use(express.urlencoded({extended: true}));

app.get('/', (req, res) => {
    res.sendFile('js/index.html', {root: __dirname });// When you enter the url localhost:3000/ you get the index.html file.
});


app.get('/getExersises', (req,res) =>{
    con = new Client({ // Establish a connection with the database called lts_ets_pro 
        user: "",
        host: "",
        database: "lts_ets_pro",
        password: ""
    });
    con.connect(function(err){ // When the connection attempt was successful this will run  
        if(err) throw err// If there had been an error connecting to the database it will throw the error
        con.query("select id, name, created from exm.exercise order by created",function(err,result,fields){
            if(err) 
                throw err;
            var payload = [];
            for(var i = 0; i < result.rows.length;i++)
            {
                
                // This will just put the lat and lon variables in a point variable and then append the point to the payload
                var exersise = {exersise_id: result.rows[i].id, exersise_name: result.rows[i].name}
                payload.push(exersise);
            }
            res.send(payload)// Send the data to the client as a response
        })
    });
});
app.get('/getParticipants/p', (req,res)=> {
    con = new Client({ // Establish a connection with the database called lts_ets_pro 
        user: "",
        host: "",
        database: "lts_ets_pro",
        password: ""
    });
    con.connect(function(err){ // When the connection attempt was successful this will run  
        if(err) throw err// If there had been an error connecting to the database it will throw the error
        con.query("SELECT DISTINCT id, equipment_number, designator from ex_" + req.query.exersiseId + ".rec_participant where equipment_number IS NOT NULL order by equipment_number",function(err,result,fields){
            if(err) 
                throw err;
            var payload = [];
            for(var i = 0; i < result.rows.length;i++)
            {
                // This will just put the lat and lon variables in a point variable and then append the point to the payload
                var participant = {id: result.rows[i].id,equipment_number: result.rows[i].equipment_number, designator: result.rows[i].designator}
                payload.push(participant);
            }
            res.send(payload)// Send the data to the client as a response
        })
    });
});

app.get("/getPositions/p", (req, res) => { // This will be run when you enter the URL localhost:3000/getData/p
    con = new Client({ // Establish a connection with the database called lts_ets_pro 
        user: "",
        host: "",
        database: "lts_ets_pro",
        password: ""
    });
    con.connect(function(err){ // When the connection attempt was successful this will run  
        if(err) throw err// If there had been an error connecting to the database it will throw the error
        con.query("select sample_time, pos_lon*180/3.14159265359 as pos_lon, pos_lat*180/3.14159265359 as pos_lat, pos_z from ex_" + req.query.exersiseId + ".rec_participant_position where participant_id = " + req.query.parId + " order by sample_time",function(err,result,fields){
            // Explenation:
            // ---select sample_time, pos_lon*180/3.14159265359 as pos_lon, pos_lat*180/3.14159265359 as pos_lat, pos_z
            // This will select what variables i want to get from the table.
            // ---from ex_201.rec_participant_position
            // This defines the table i want to get data from.
            // ---where participant_id = " + req.query.parId + " 
            // I only want to take the data if it is from the participant with the participantId that has been passed from the get request
            // ---order by sample_time
            // This will just order the data by the sample_time

            if(err) 
                throw err;
            var Payload = [];
            for(var i = 0; i < result.rows.length;i++)
            {
                
                // This will just put the lat and lon variables in a point variable and then append the point to the payload
                
                var position = []; 
                position.push(result.rows[i].pos_lat);
                position.push(result.rows[i].pos_lon);
                var event = {event_type_id: -1,event_name: "Position", sample_time: result.rows[i].sample_time,position: position}
                Payload.push(event);
            }
            res.send(Payload)// Send the data to the client as a response
        })
    });
})


app.get("/getEvents/p", (req, res) => { // This will be run when you enter the URL localhost:3000/getEvents/p
    con = new Client({ // Establish a connection with the database called lts_ets_pro 
        user: "",
        host: "",
        database: "lts_ets_pro",
        password: ""
    });
    
    con.connect(function(err){ // When the connection attempt was successful this will run. 
        if(err) throw err; // If there had been an error connecting to the database it will throw the error
        con.query("select E.event_type_id, T.name, E.participant_id, E.sample_time,  E.position_x*180/3.14159265359 as position_x,  E.position_y*180/3.14159265359 as position_y from ex_" + req.query.exersiseId + ".eem_event E JOIN pdm.pdm_event_type T ON T.id = E.event_type_id where participant_id = " + req.query.parId + " and event_type_id IN (" + req.query.eventIds + ") order by sample_time",function(err,result,fields){
            // Explenation:
            // ---select T.name, E.participant_id, E.sample_time,  E.position_x*180/3.14159265359 as position_x,  E.position_y*180/3.14159265359 as position_y 
            // This will select what variables i want to get from the table. The E and T will be different tables that will be defined in the next step.
            // ---from ex_201.eem_event E JOIN pdm.pdm_event_type T
            // This defines the tables i want to get data from.
            // ---ON T.id = E.event_type_id
            // This will look up the correct T.name by the event_type_id of the given event
            // ---where participant_id = " + req.query.parId + " and event_type_id IN (" + req.query.eventIds + ")
            // I only want to take the data if it is from the participant with the correct participantId and event_type_id that has been passed from the get request and
            // ---order by sample_time
            // This will just order the data by the sample_time

            if(err) 
                throw err;
            var payload = [];
            for(var i = 0; i < result.rows.length;i++)
            {
                // This will just put the data in a event object
                var position = [];
                position.push(result.rows[i].position_y);
                position.push(result.rows[i].position_x);
                var event = {event_type_id: result.rows[i].event_type_id,event_name: result.rows[i].name, sample_time: result.rows[i].sample_time,position: position}
                payload.push(event);
            }
            res.send(payload) // Send the data to the client as a response
        })
    });
})

app.listen(port, () => {
    console.log(`Example app listening on port ${port}`)
})