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

#include "glfw_keycodes.h"

@implementation KeyboardInput

+ (void)initKeycodeTable {
    if (@available(iOS 13.4, *)) {
        keycodeTable = [[NSMutableDictionary alloc] init];

        // 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)] intValue];
    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