stick-figure-mmo/static/inputhandler.js

class Command {
    execute() { }
    toNetwork() {
        return null;
    }
}

class PunchCmd extends Command {
    execute(p) {
        p.punch();
    }
    toNetwork(p) {
        return {
            Id: p.id,
            Action: ' ',
            ActionType: "keyDown"
        };
    }
}

class JumpCmd extends Command {
    execute(p) {
        p.jump();
    }
    toNetwork(p) {
        return {
            Id: p.id,
            Action: 'w',
            ActionType: 'keyDown'
        };
    }
}

class CrouchPressCmd extends Command {
    execute(p) {
        p.crouching = true;
    }
    toNetwork(p) {
        return {
            Id: p.id,
            Action: 's',
            ActionType: 'keyDown'
        };
    }
}

class CrouchUnpressCmd extends Command {
    execute(p) {
        p.crouching = false;
    }
    toNetwork(p) {
        return {
            Id: p.id,
            Action: 's',
            ActionType: 'keyUp'
        };
    }
}

class MoveLeftPressCmd extends Command {
    execute(p) {
        p.keys.a = true;
    }
    toNetwork(p) {
        return {
            Id: p.id,
            Action: 'a',
            ActionType: 'keyDown'
        };

    }
}

class MoveLeftUnpressCmd extends Command {
    execute(p) {
        p.keys.a = false;
    }
    toNetwork(p) {
        return {
            Id: p.id,
            Action: 'a',
            ActionType: 'keyUp'
        };

    }
}

class MoveRightPressCmd extends Command {
    execute(p) {
        p.keys.d = true;
    }
    toNetwork(p) {
        return {
            Id: p.id,
            Action: 'd',
            ActionType: 'keyDown'
        };
    }
}

class MoveRightUnpressCmd extends Command {
    execute(p) {
        p.keys.d = false;
    }
    toNetwork(p) {
        return {
            Id: p.id,
            Action: 'd',
            ActionType: 'keyUp'
        };
    }
}

class TalkCmd extends Command {
    constructor(message) {
        super();
        this.message = message;
    }
    execute(p) {
        p.talk(this.message);
    }
    toNetwork(p) {
        return {
            Id: p.id,
            Action: 't',
            ActionType: '',
            Message: this.message
        }
    }
}

class DisconnectedCmd extends Command {
    execute() { }
    toNetwork(p) {
        return {
            Id: p.id,
            Action: "disconnected",
            ActionType: ""
        };
    }
}

export class InputHandler {
    constructor(game) {
        this.game = game;

        this.downMap = new Map([
            [' ', () => new PunchCmd()],
            ['w', () => new JumpCmd()],
            ['s', () => new CrouchPressCmd()],
            ['a', () => new MoveLeftPressCmd()],
            ['d', () => new MoveRightPressCmd()],
        ]);

        this.upMap = new Map([
            ['s', () => new CrouchUnpressCmd()],
            ['a', () => new MoveLeftUnpressCmd()],
            ['d', () => new MoveRightUnpressCmd()],
        ]);
    }

    handleKeyDown(e, player) {
        const key = e.code === 'Space' ? ' ' : (e.key || '').toLowerCase();
        const k = this.downMap.get(key);
        if (!k) {
            return;
        }

        e.preventDefault();
        e.stopPropagation();
        this.dispatch(k(), player)
    }

    handleKeyUp(e, player) {
        const key = e.code === "Space" ? ' ' : e.key;
        const k = this.upMap.get(key);
        if (!k) {
            return;
        }
        e.preventDefault();
        e.stopPropagation();
        this.dispatch(k(), player)
    }

    dispatch(cmd, player) {
        if (!player) return;
        cmd.execute(player, this.game);
        if (player.isLocal) {
            const msg = cmd.toNetwork(player);
            if (msg) {
                this.game._send({
                    ...msg,
                    PosX: Math.floor(player.x),
                    PosY: Math.floor(player.y),
                    Facing: player.facing,
                    Ts: Date.now(),
                });
            }
        }
    }

    handleNetworkMessage(data) {
        this.game._ensurePlayer(data.Id);
        const p = this.game.players?.[data.Id];
        if (!p) {
            return;
        }

        if (typeof data.PosX === "number") {
            p._lastTx = p._tx ?? data.PosX;
            p._tx = data.PosX;
        }
        if (typeof data.PosY === "number") {
            p._lastTy = p._ty ?? data.PosY;
            p._ty = data.PosY;
        }
        if (typeof data.Facing === "number") {
            p._tFacing = data.Facing;
        }

        p._lastUpdateTime = Date.now();

        const action = data.Action;
        const actionType = data.ActionType;

        const apply = (cmd) => cmd && cmd.execute(p, this.game);

        switch (action) {
            case 'disconnected':
                delete this.game.players[data.Id];
                break;
            case 't':
                apply(new TalkCmd(data.Message ?? ""));
                break;
            case ' ':
                apply(new PunchCmd());
                break;
            case 'w':
                apply(new JumpCmd());
                break;
            case 's':
                apply(actionType === 'keyDown' ? new CrouchPressCmd() : new CrouchUnpressCmd());
                break;
            case 'a':
                apply(actionType === 'keyDown' ? new MoveLeftPressCmd() : new MoveLeftUnpressCmd());
                break;
            case 'd':
                apply(actionType === 'keyDown' ? new MoveRightPressCmd() : new MoveRightUnpressCmd());
                break;
        }
    }
    releaseAll(player) {
        const cmds = [];
        if (player.keys?.a) cmds.push(new MoveLeftUnpressCmd());
        if (player.keys?.d) cmds.push(new MoveRightUnpressCmd());
        if (player.crouching) cmds.push(new CrouchUnpressCmd());
        for (const c of cmds) this.dispatch(c, player);
    }
}