Leader key implementation (#326)

* implements leader key for planck experimental

* allows override of leader timeout

* adds ability to use the leader key in seq

* fixes leader keycode

* adds chording prototype

* fixes keycode detection

* moves music mode to quantum.c

* disables chording by default

* updates process_action functions to return bool

1 files changed, 167 insertions, 0 deletions

diff --git a/quantum/quantum.c b/quantum/quantum.c
new file mode 100644
index 0000000000..e274d846f2
--- /dev/null
+++ b/quantum/quantum.c
@@ -0,0 +1,167 @@
+#include "quantum.h"
+
+__attribute__ ((weak))
+void matrix_init_kb(void) {}
+
+__attribute__ ((weak))
+void matrix_scan_kb(void) {}
+
+__attribute__ ((weak))
+bool process_action_kb(keyrecord_t *record) {
+  return true;
+}
+
+__attribute__ ((weak))
+void leader_start(void) {}
+
+__attribute__ ((weak))
+void leader_end(void) {}
+
+#ifdef AUDIO_ENABLE
+  uint8_t starting_note = 0x0C;
+  int offset = 0;
+  bool music_activated = false;
+#endif
+
+// Leader key stuff
+bool leading = false;
+uint16_t leader_time = 0;
+
+uint16_t leader_sequence[3] = {0, 0, 0};
+uint8_t leader_sequence_size = 0;
+
+// Chording stuff
+#define CHORDING_MAX 4
+bool chording = false;
+
+uint8_t chord_keys[CHORDING_MAX] = {0};
+uint8_t chord_key_count = 0;
+uint8_t chord_key_down = 0;
+
+bool keys_chord(uint8_t keys[]) {
+  uint8_t keys_size = sizeof(keys)/sizeof(keys[0]);
+  bool pass = true;
+  uint8_t in = 0;
+  for (uint8_t i = 0; i < chord_key_count; i++) {
+    bool found = false;
+    for (uint8_t j = 0; j < keys_size; j++) {
+      if (chord_keys[i] == (keys[j] & 0xFF)) {
+        in++; // detects key in chord
+        found = true;
+        break;
+      }
+    }
+    if (found)
+      continue;
+    if (chord_keys[i] != 0)  {
+      pass = false; // makes sure rest are blank
+    }
+  }
+  return (pass && (in == keys_size));
+}
+
+bool process_action_quantum(keyrecord_t *record) {
+
+  /* This gets the keycode from the key pressed */
+  keypos_t key = record->event.key;
+  uint16_t keycode;
+
+  #if !defined(NO_ACTION_LAYER) && defined(PREVENT_STUCK_MODIFIERS)
+    uint8_t layer;
+
+    if (record->event.pressed) {
+      layer = layer_switch_get_layer(key);
+      update_source_layers_cache(key, layer);
+    } else {
+      layer = read_source_layers_cache(key);
+    }
+    keycode = keymap_key_to_keycode(layer, key);
+  #else
+    keycode = keymap_key_to_keycode(layer_switch_get_layer(key), key);
+  #endif
+
+  #ifdef AUDIO_ENABLE
+    if (music_activated) {
+      if (record->event.pressed) {
+          play_note(((double)220.0)*pow(2.0, -4.0)*pow(2.0,(starting_note + SCALE[record->event.key.col + offset])/12.0+(MATRIX_ROWS - record->event.key.row)), 0xF);
+      } else {
+          stop_note(((double)220.0)*pow(2.0, -4.0)*pow(2.0,(starting_note + SCALE[record->event.key.col + offset])/12.0+(MATRIX_ROWS - record->event.key.row)));
+      }
+      if (keycode < 0xFF) // ignores all normal keycodes, but lets RAISE, LOWER, etc through
+        return false;
+    }
+  #endif
+
+
+
+#ifndef DISABLE_LEADER
+  // Leader key set-up
+  if (record->event.pressed) {
+    if (!leading && keycode == KC_LEAD) {
+      leader_start();
+      leading = true;
+      leader_time = timer_read();
+      leader_sequence_size = 0;
+      leader_sequence[0] = 0;
+      leader_sequence[1] = 0;
+      leader_sequence[2] = 0;
+      return false;
+    }
+    if (leading && timer_elapsed(leader_time) < LEADER_TIMEOUT) {
+      leader_sequence[leader_sequence_size] = keycode;
+      leader_sequence_size++;
+      return false;
+    }
+  }
+#endif
+
+#define DISABLE_CHORDING
+#ifndef DISABLE_CHORDING
+
+  if (keycode >= 0x5700 && keycode <= 0x57FF) {
+    if (record->event.pressed) {
+      if (!chording) {
+        chording = true;
+        for (uint8_t i = 0; i < CHORDING_MAX; i++)
+          chord_keys[i] = 0;
+        chord_key_count = 0;
+        chord_key_down = 0;
+      }
+      chord_keys[chord_key_count] = (keycode & 0xFF);
+      chord_key_count++;
+      chord_key_down++;
+      return false;
+    } else {
+      if (chording) {
+        chord_key_down--;
+        if (chord_key_down == 0) {
+          chording = false;
+          // Chord Dictionary
+          if (keys_chord((uint8_t[]){KC_ENTER, KC_SPACE})) {
+            register_code(KC_A);
+            unregister_code(KC_A);
+            return false;
+          }
+          for (uint8_t i = 0; i < chord_key_count; i++) {
+            register_code(chord_keys[i]);
+            unregister_code(chord_keys[i]);
+            return false;
+          }
+        }
+      }
+    }
+  }
+
+#endif
+
+
+  return process_action_kb(record);
+}
+
+void matrix_init_quantum() {
+  matrix_init_kb();
+}
+
+void matrix_scan_quantum() {
+  matrix_scan_kb();
+}
\ No newline at end of file