Added can driver

can.js

@@ -0,0 +1,118 @@
+const can = require("socketcan");
+const csv = require("fast-csv");
+const fs = require("fs");
+
+const can_conf = require("./app/config/can.conf");
+const map_conf = require("./app/config/map.conf");
+
+var map_rpm = [];
+var map_throttle = [];
+
+var loaded_map_name = "";
+var loaded_map_data = [];
+
+var throttle_output = 0;
+
+var channel = can.createRawChannel(can_conf.network_id, true);
+
+for (let i = 0; i <= map_conf.steps; i++) {
+    map_rpm[i] = i * (map_conf.max_rpm / map_conf.steps);
+    map_throttle[i] = i * (map_conf.max_throttle / map_conf.steps);
+}
+
+const current_id = (0x01 << 5) | can_conf.controller.id;
+const brake_current_id = (0x02 << 5) | can_conf.controller.id;
+
+function parseMap(filename) {
+    loaded_map_data = [];
+
+    return new Promise((resolve, reject) => {
+        csv.parseFile(`app/storage/${filename}`, { comment: "#" })
+            .on('error', error => reject(error))
+            .on('data', row => loaded_map_data.push(row))
+            .on('end', () => { loaded_map_name = filename; resolve() });
+    });
+}
+
+function getMapIndex(array, input) {
+    if (array.length === 0) {
+        return -1;
+    }
+
+    let left = 0;
+    let right = array.length - 1;
+
+    while (left <= right) {
+        const mid = Math.floor((left + right) / 2);
+
+        if (array[mid] === input) {
+            return mid;
+        } else if (array[mid] < input) {
+            left = mid + 1;
+        } else {
+            right = mid - 1;
+        }
+    }
+
+    if (left >= array.length) {
+        return array.length - 1;
+    }
+    if (right < 0) {
+        return 0;
+    }
+    return Math.abs(array[left] - input) < Math.abs(array[right] - input) ? left : right;
+}
+
+channel.addListener("onMessage", async function (message) {
+    if (fs.existsSync(map_conf.selected_map_path)) {
+        let enabled_map_name = fs.readFileSync(map_conf.selected_map_path);
+
+        if (enabled_map_name != "") {
+            if (loaded_map_name != enabled_map_name) {
+                await parseMap(enabled_map_name);
+            }
+
+            if (message.id == can_conf.apps_id) {
+                const apps_percentage = ((message.data[1] << 8) | message.data[0]) / 1000;
+                let pos = getMapIndex(map_throttle, apps_percentage);
+
+                throttle_output = loaded_map_data[pos][2];
+            } else {
+                let packet_id = message.id >> 5;
+                let node_id = message.id & 0x1F;
+
+                if ((node_id == can_conf.controller.id) && (packet_id == 0x20)) {
+                    let ERPM = message.data[0] << 3 * 8 | message.data[1] << 2 * 8 | message.data[2] << 8 | message.data[3];
+
+                    if (throttle_output > 0) {
+                        let max_current = loaded_map_data[getMapIndex(map_rpm, ERPM / can_conf.motor_poles)][0];
+                        let current = throttle_output * max_current * 10;
+
+                        channel.send({
+                            id: current_id,
+                            ext: false,
+                            data: Buffer.from([(current >> 8) & 0xFF, current & 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF])
+                        });
+                    } else if (throttle_output < 0) {
+                        let max_brake_current = loaded_map_data[getMapIndex(map_rpm, ERPM / can_conf.motor_poles)][1];
+                        let brake_current = throttle_output * max_brake_current * 10;
+
+                        channel.send({
+                            id: brake_current_id,
+                            ext: false,
+                            data: Buffer.from([(brake_current >> 8) & 0xFF, brake_current & 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF])
+                        });
+                    } else {
+                        channel.send({
+                            id: current_id,
+                            ext: false,
+                            data: Buffer.from([0, 0, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF])
+                        });
+                    }
+                }
+            }
+        }
+    }
+});
+
+channel.start();