#import "KeyboardInput.h"
#import "../utils.h"

#include "../glfw_keycodes.h"

@implementation KeyboardInput

int keycodeTable[UIKeyboardHIDUsageKeyboardRightGUI+1];

+ (void)initKeycodeTable {
    if (@available(iOS 13.4, *)) {
        // A-Z keys
        for (int i = UIKeyboardHIDUsageKeyboardA; i <= UIKeyboardHIDUsageKeyboardZ; i++) {
            keycodeTable[i] = i - UIKeyboardHIDUsageKeyboardA + GLFW_KEY_A;
        }

        // 0-9 keys
        keycodeTable[UIKeyboardHIDUsageKeyboard0] = GLFW_KEY_0;
        for (int i = UIKeyboardHIDUsageKeyboard1; i <= UIKeyboardHIDUsageKeyboard9; i++) {
            keycodeTable[i] = i - UIKeyboardHIDUsageKeyboard1 + GLFW_KEY_1;
        }

        // Arrow keys
        keycodeTable[UIKeyboardHIDUsageKeyboardUpArrow] = GLFW_KEY_DPAD_UP;
        keycodeTable[UIKeyboardHIDUsageKeyboardDownArrow] = GLFW_KEY_DPAD_DOWN;
        keycodeTable[UIKeyboardHIDUsageKeyboardLeftArrow] = GLFW_KEY_DPAD_LEFT;
        keycodeTable[UIKeyboardHIDUsageKeyboardRightArrow] = GLFW_KEY_DPAD_RIGHT;

        keycodeTable[UIKeyboardHIDUsageKeyboardComma] = GLFW_KEY_COMMA;
        keycodeTable[UIKeyboardHIDUsageKeyboardPeriod] = GLFW_KEY_PERIOD;

        // Alt keys
        keycodeTable[UIKeyboardHIDUsageKeyboardLeftAlt] = GLFW_KEY_LEFT_ALT;
        keycodeTable[UIKeyboardHIDUsageKeyboardRightAlt] = GLFW_KEY_RIGHT_ALT;

        // Control keys
        keycodeTable[UIKeyboardHIDUsageKeyboardLeftControl] = GLFW_KEY_LEFT_CONTROL;
        keycodeTable[UIKeyboardHIDUsageKeyboardRightControl] = GLFW_KEY_RIGHT_CONTROL;

        // Shift keys
        keycodeTable[UIKeyboardHIDUsageKeyboardLeftShift] = GLFW_KEY_LEFT_SHIFT;
        keycodeTable[UIKeyboardHIDUsageKeyboardRightShift] = GLFW_KEY_RIGHT_SHIFT;

        // Bracket keys
        keycodeTable[UIKeyboardHIDUsageKeyboardOpenBracket] = GLFW_KEY_LEFT_BRACKET;
        keycodeTable[UIKeyboardHIDUsageKeyboardCloseBracket] = GLFW_KEY_RIGHT_BRACKET;

        // Slash keys
        keycodeTable[UIKeyboardHIDUsageKeyboardSlash] = GLFW_KEY_SLASH;
        keycodeTable[UIKeyboardHIDUsageKeyboardBackslash] = GLFW_KEY_BACKSLASH;

        // Page keys
        keycodeTable[UIKeyboardHIDUsageKeyboardPageUp] = GLFW_KEY_PAGE_UP;
        keycodeTable[UIKeyboardHIDUsageKeyboardPageDown] = GLFW_KEY_PAGE_DOWN;

        // Some other keys
        keycodeTable[UIKeyboardHIDUsageKeyboardHome] = GLFW_KEY_HOME;
        keycodeTable[UIKeyboardHIDUsageKeyboardEscape] = GLFW_KEY_ESCAPE;
        keycodeTable[UIKeyboardHIDUsageKeyboardTab] = GLFW_KEY_TAB;
        keycodeTable[UIKeyboardHIDUsageKeyboardReturnOrEnter] = GLFW_KEY_ENTER;
        keycodeTable[UIKeyboardHIDUsageKeyboardSpacebar] = GLFW_KEY_SPACE;
        keycodeTable[UIKeyboardHIDUsageKeyboardDeleteOrBackspace] = GLFW_KEY_BACKSPACE;
        keycodeTable[UIKeyboardHIDUsageKeyboardDeleteForward] = GLFW_KEY_DELETE;
        keycodeTable[UIKeyboardHIDUsageKeyboardGraveAccentAndTilde] = GLFW_KEY_GRAVE_ACCENT;

        keycodeTable[UIKeyboardHIDUsageKeyboardHyphen] = GLFW_KEY_MINUS;
        keycodeTable[UIKeyboardHIDUsageKeyboardEqualSign] = GLFW_KEY_EQUAL;
        keycodeTable[UIKeyboardHIDUsageKeyboardSemicolon] = GLFW_KEY_SEMICOLON;

        // Lock keys
        keycodeTable[UIKeyboardHIDUsageKeyboardCapsLock] = GLFW_KEY_CAPS_LOCK;
        keycodeTable[UIKeyboardHIDUsageKeypadNumLock] = GLFW_KEY_NUM_LOCK;
        keycodeTable[UIKeyboardHIDUsageKeyboardScrollLock] = GLFW_KEY_SCROLL_LOCK;

        // Numpad keys
        keycodeTable[UIKeyboardHIDUsageKeypadSlash] = GLFW_KEY_NUMPAD_DIVIDE;
        keycodeTable[UIKeyboardHIDUsageKeypadAsterisk] = GLFW_KEY_NUMPAD_MULTIPLY;
        keycodeTable[UIKeyboardHIDUsageKeypadHyphen] = GLFW_KEY_NUMPAD_SUBTRACT;
        keycodeTable[UIKeyboardHIDUsageKeypadPlus] = GLFW_KEY_NUMPAD_ADD;
        keycodeTable[UIKeyboardHIDUsageKeypadEnter] = GLFW_KEY_NUMPAD_ENTER;
        keycodeTable[UIKeyboardHIDUsageKeypadEqualSign] = GLFW_KEY_NUMPAD_EQUAL;
        keycodeTable[UIKeyboardHIDUsageKeypad0] = GLFW_KEY_NUMPAD_0;
        for (int i = UIKeyboardHIDUsageKeypad1; i <= UIKeyboardHIDUsageKeypad9; i++) {
            keycodeTable[i] = i - UIKeyboardHIDUsageKeypad1 + GLFW_KEY_NUMPAD_1;
        }

        // Function keys
        for (int i = UIKeyboardHIDUsageKeyboardF1; i <= UIKeyboardHIDUsageKeyboardF12; i++) {
            keycodeTable[i] = i - UIKeyboardHIDUsageKeyboardF1 + GLFW_KEY_F1;
        }
    }
}

+ (BOOL)sendKeyEvent:(UIKey *)key down:(BOOL)isDown API_AVAILABLE(ios(13.4)) {
    char modifiers = 0;

    // convert UIKey's modifiers to GLFW
    if (key.modifierFlags & UIKeyModifierAlphaShift) {
        modifiers |= GLFW_MOD_CAPS_LOCK;
    }
    if (key.modifierFlags & UIKeyModifierShift) {
        modifiers |= GLFW_MOD_SHIFT;
    }
    if (key.modifierFlags & UIKeyModifierAlternate) {
        modifiers |= GLFW_MOD_ALT;
    }
    if (key.modifierFlags & UIKeyModifierControl) {
        modifiers |= GLFW_MOD_CONTROL;
    }

    // send the keycode
    int keycode = keycodeTable[key.keyCode];
    if (keycode != 0) {
        CallbackBridge_nativeSendKey(keycode, 0 /* scancode */, isDown, modifiers);
    } else {
        NSLog(@"KeyboardInput: Unhandled key %lu", (unsigned long)key.keyCode);
    }

    // key.characters.length < 11: skip sending characters if the string starts with UIKeyInput
    if (isDown && key.characters.length < 11) {
        for (int i = 0; i < key.characters.length; i++) {
            int keychar = [key.characters characterAtIndex:i];
            CallbackBridge_nativeSendCharMods(keychar, modifiers);
            CallbackBridge_nativeSendChar(keychar);
        }
    }

    return keycode != 0 || isDown;
}

@end