Added basic spellchecker

src/commands.h

@@ -27,6 +27,23 @@
 // 0x02: FFT Animation
 #define CMD_SEND_STATE 0x02
 
+// Sent by keyboard to host when a complete word is typed.
+// Host checks if this is a known word.
+// If it is not, host responds with the same CMD (see below).
+//
+// Packet structure (sent by keyboard):
+// Data:		| cmd | word length |  keycodes  |
+// # of Bytes:	|  1  |      1      |     ?      |
+//
+// word length: number of bytes in `keycodes` block
+//
+//
+// Packet structure (sent by host):
+// Data:		| cmd | typo? |
+// # of Bytes:	|  1  |   1   |
+//
+// typo: If this is 0x01, the word we got was a typo.
+#define CMD_SPELLCHECK_WORD 0x04
 
 // Animation data. Sent by host.
 //

src/config.h

@@ -1,5 +1,11 @@
 #pragma once
 
+
+// Sleep this many millis after each loop.
+// Prevents absurd cpu usage.
+#define LOOP_SLEEP_MS 20
+
+
 // USB device params
 #define HID_VENDOR_ID 0x3297
 #define HID_PRODUCT_ID 0x4976

src/dict.cpp

@@ -0,0 +1,16 @@
+#include "dict.hpp"
+
+std::unordered_set<std::string> word_dict;
+
+void load_file() {
+	std::ifstream file("resources/google-10000-english-usa-no-swears.txt");
+	if (file.is_open()) {
+		std::string line;
+		while (std::getline(file, line)) {
+			// using printf() in all tests for consistency
+			//printf("%s", line.c_str());
+			word_dict.insert(line.c_str());
+		}
+		file.close();
+	}
+}

src/dict.hpp

@@ -0,0 +1,10 @@
+#pragma once
+
+#include <fstream>
+#include <unordered_set>
+#include <string>
+
+extern std::unordered_set<std::string> word_dict;
+
+
+void load_file();

src/ergodox.cpp

@@ -206,10 +206,9 @@ bool Ergodox::read() {
 		// If keyboard sends a state packet, parse it.
 		case CMD_SEND_STATE:
 			if (animation_mode != read_buf[1]) {
-				spdlog::info("Mode set to {0:x}", read_buf[1]);
+				spdlog::info("Mode set to 0x{0:02x}", read_buf[1]);
 				animation_mode = read_buf[1];
 			}
-
 			// Main code should not parse state packets.
 			return false;
 	}

src/main.cpp

@@ -11,6 +11,8 @@
 // MPD client
 #include "mpd/client.h"
 
+#include <string>
+
 // Local files
 #include "utility/bitmap.hpp"
 #include "utility/buffer.hpp"
@@ -21,6 +23,7 @@
 
 #include "spdlog/spdlog.h"
 
+#include "dict.hpp"
 
 // TODO:
 //
@@ -58,6 +61,11 @@ const size_t height = BOTTOM_SKIP + KB_RESOLUTION + TOP_SKIP;
 
 int main(int argc, char *argv[]) {
 
+	spdlog::info("Loading dictionary...");
+	load_file();
+	spdlog::info("done!");
+
+
 	spdlog::set_level(spdlog::level::info);
 
 	// buffer size for waveform:
@@ -119,7 +127,6 @@ int main(int argc, char *argv[]) {
 					buf.update();
 					fft.update(buf);
 
-					hid_buf[0] = CMD_ANIM_DATA_fft;
 					for (size_t i = 0; i < 10; i++) {
 						// Get height from fft, apply bottom_skip
 						ssize_t h = fft.get_output()[i] - BOTTOM_SKIP;
@@ -129,11 +136,11 @@ int main(int argc, char *argv[]) {
 						h = h>KB_RESOLUTION ? KB_RESOLUTION : h;
 						h = h<0 ? 0 : h;
 
-						hid_buf[i + 1] = h;
+						hid_buf[i] = h;
 					}
+					Dox.write(CMD_ANIM_DATA, hid_buf, Dox.packet_size);
 				}
 
-				Dox.write(CMD_ANIM_DATA, hid_buf, Dox.packet_size);
 
 				t = std::chrono::steady_clock::now();
 			}
@@ -148,13 +155,37 @@ int main(int argc, char *argv[]) {
 				uint8_t cmd = Dox.read_buf[0];
 
 				switch(cmd) {
-					case CMD_SEND_STATE:
+					case CMD_SPELLCHECK_WORD:
+						char word_chars[Dox.read_buf[1] + 1];
+
+						for (int i=0; i < Dox.read_buf[1]; i++) {
+							// A in ascii:
+							// a in ascii: 0x61
+							// KC_A: 0x04
+							word_chars[i] = Dox.read_buf[i + 2] + 0x5D;
+						}
+						word_chars[Dox.read_buf[1]] = 0x00; // Terminate with null char
+
+						std::string word = std::string(word_chars);
+
+						if (word_dict.find(word) == word_dict.end()) {
+							hid_buf[0] = 0x01;
+							Dox.write(CMD_SPELLCHECK_WORD, hid_buf, Dox.packet_size);
+							spdlog::info("Got typo: \"{0:s}\" not in dict", word);
+						}
 						break;
 				}
 			}
+
 		} else {
 			Dox.connect_loop();
 		}
+
+		// Sleep for a bit so we don't consume
+		// 100% of a cpu.
+		std::this_thread::sleep_for(
+			std::chrono::milliseconds(LOOP_SLEEP_MS)
+		);
 	}
 
 	mpd_connection_free(conn);