import { Cast } from "../utils/cast";
import { Runtime } from "./runtime";
import { KEYBOARD_KEYS } from "../../type/engine/keyboad";
import { InputMedia } from "../utils/inputMedia";
import { ScratchElement } from "../gui/scratchElement";
declare type POST_DATA = {
    isDown: boolean,
    key : string,
};

const KEY_NAME_LIST:string[] = Object.keys(KEYBOARD_KEYS).map((name:string) => KEYBOARD_KEYS[name]);
/**
 * @hidden
 */
const KeysToBlock = new Set([
    'ArrowUp',      // 上向き矢印
    'ArrowDown',    // 下向き矢印
    'ArrowLeft',    // 左向き矢印 (横スクロール防止)
    'ArrowRight',   // 右向き矢印 (横スクロール防止)
    ' ',            // スペースキー (ページダウン防止)
    'PageUp',       // ページアップ
    'PageDown',     // ページダウン
    'Home',         // ホーム
    'End'           // エンド
]);

export class Keyboard {
    private _keysPressed: string[] = [];
    private _runtime : Runtime;
    private _spaceStopPropagation!: boolean;
    constructor ( runtime: Runtime ) {
        this._runtime = runtime;
        const me = this;
        const keyDown = (e: KeyboardEvent) => {
            // 押されたキーがブロック対象のリストに含まれているか判定
            if (KeysToBlock.has(e.key)) {
                // ブラウザのデフォルト挙動（スクロールなど）をキャンセル
                e.preventDefault();
            }
            const scratchKey = this._keyStringToScratchKey(e.key);
            this.pressKey(scratchKey);
        }
        const keyUp = (e:KeyboardEvent) => {
            const scratchKey = this._keyStringToScratchKey(e.key);
            this.releaseKey(scratchKey);
        }

        document.addEventListener('keydown', keyDown, { passive: false }); // preventDefaultを確実に動作させるためのオプション
        document.addEventListener('keyup', keyUp, {passive: false});
        this._spaceStopPropagation = true;
    }
    pressKey(keyName:string) {
        const data: POST_DATA = {
            isDown: true,
            key : keyName,
        };
        this.postData(data);
    }
    releaseKey(keyName:string) {
        const data: POST_DATA = {
            isDown: false,
            key : keyName,
        };
        this.postData(data);
    }
    postData(data: POST_DATA) {
        if (!data.key) return;
        //const scratchKey = this._keyStringToScratchKey(data.key);
        const scratchKey = data.key;
        if (scratchKey === '') return;
        const index = this._keysPressed.indexOf(scratchKey);
        if (data.isDown) {
            this._runtime.emit('KEY_PRESSED', scratchKey);
            if (index < 0) {
                this._keysPressed.push(scratchKey);
            }
        } else if (index > -1) {
            // If already present, remove from the list.
            this._keysPressed.splice(index, 1);
        }
    }
    get spaceStopPropagation() : boolean {
        return this._spaceStopPropagation;
    }
    set spaceStopPropagation(spaceStopPropagation: boolean) {
        this._spaceStopPropagation = spaceStopPropagation;
    }
    /**
     * キーが押されているかを判定する
     * @param  {string|number} keyArg key argument.
     * @return {boolean} Is the specified key down?
     */
    keyIsDown(keyArg?: string): boolean {
         if (!keyArg || keyArg === 'any') {
            return this._keysPressed.length > 0;
        }
        const scratchKey = this._keyArgToScratchKey(keyArg);
        return this._keysPressed.indexOf(scratchKey) > -1;
    }

    _scratchKeyToKeyString( scratchKey: string ): string {
        switch (scratchKey) {
        case KEYBOARD_KEYS.SPACE:
            return ' ';
        case KEYBOARD_KEYS.LEFT:
            return 'ArrowLeft';
        case KEYBOARD_KEYS.UP:
            return 'ArrowUp';
        case KEYBOARD_KEYS.RIGHT:
            return 'ArrowRight';
        case KEYBOARD_KEYS.DOWN:
            return 'ArrowDown';
        case KEYBOARD_KEYS.ENTER:
            return 'Enter';
        case KEYBOARD_KEYS.ESCAPE:
            return 'Escape';
        }
        if(scratchKey.length == 0) {
            // 1文字の場合は、空文字
            return '';
        }else if(scratchKey.length == 1) {
            // １文字のキーは大文字にする
            return scratchKey.toUpperCase();
        }else {
            // 2文字以上の場合は、先頭の文字にする（大文字）
            const firstCharacter = scratchKey.charAt(0);
            return firstCharacter.toUpperCase();
        }
    }

    /**
     * Convert from a keyboard event key name to a Scratch key name.
     * @param  {string} keyString the input key string.
     * @return {string} the corresponding Scratch key, or an empty string.
     */
    _keyStringToScratchKey (keyString: string) : string {
        keyString = Cast.toString(keyString);
        // Convert space and arrow keys to their Scratch key names.
        switch (keyString) {
        case ' ': return KEYBOARD_KEYS.SPACE;
        case 'ArrowLeft':return KEYBOARD_KEYS.LEFT;
        case 'Left': return KEYBOARD_KEYS.LEFT;
        case 'ArrowUp':return KEYBOARD_KEYS.UP;
        case 'Up': return KEYBOARD_KEYS.UP;
        case 'Right': return KEYBOARD_KEYS.RIGHT;
        case 'ArrowRight': return KEYBOARD_KEYS.RIGHT;
        case 'Down': return KEYBOARD_KEYS.DOWN;
        case 'ArrowDown': return KEYBOARD_KEYS.DOWN;
        case 'Enter': return KEYBOARD_KEYS.ENTER;
        case 'Escape': return KEYBOARD_KEYS.ESCAPE;
        }
        // 上記以外の ２文字以上のキーは空文字に変える
        if (keyString.length > 1) {
            return '';
        }
        // 上記以外の １文字のキーは大文字にする
        return keyString.toUpperCase();
    }

    /**
     * Convert from a block argument to a Scratch key name.
     * 
     * @param  {string|number} keyArg the input arg.
     * @return {string} the corresponding Scratch key.
     */
    _keyArgToScratchKey (keyArg: string|number) : string {
        // If a number was dropped in, try to convert from ASCII to Scratch key.
        if (typeof keyArg === 'number') {
            // Check for the ASCII range containing numbers, some punctuation,
            // and uppercase letters.
            if (keyArg >= 48 && keyArg <= 90) {
                return String.fromCharCode(keyArg);
            }
            switch (keyArg) {
            case 32: return KEYBOARD_KEYS.SPACE;
            case 37: return KEYBOARD_KEYS.LEFT;
            case 38: return KEYBOARD_KEYS.UP;
            case 39: return KEYBOARD_KEYS.RIGHT;
            case 40: return KEYBOARD_KEYS.DOWN;
            }
        }

        keyArg = Cast.toString(keyArg);

        // If the arg matches a special key name, return it.
        if (KEY_NAME_LIST.includes(keyArg)) {
            return keyArg;
        }

        // Use only the first character.
        if (keyArg.length > 1) {
            keyArg = keyArg[0];
        }

        // Check for the space character.
        if (keyArg === ' ') {
            return KEYBOARD_KEYS.SPACE;
        }

        return keyArg.toUpperCase();
    }

    
}