player: {
    hp: 100,
    inventory: [
        {
            id: "dagger",
            x: 0,
            y: 0,
            name: "Swiss army knife",
            description: "Your trustworthy army knife will never let you down",
            useTimes: infinite,
            value: 5,
            actions: {}
        },
        {
            id: "potion",
            x: 0,
            y: 0,
            name: "Small healing potion",
            description: "Will recover you from small injuries",
            useTimes: 5,
            value: 5,
            actions: {}
        }
    ]
}

levels: [
    {
        layout: {
            | * * * * * * *
            | * s . . . e *
            | * * * * * * *
        },
        items: [],
        entities: []
    },
    {
        layout: {
            | x x * * * x x x x
            | x x * . * x x x x
            | * * * . * * * * *
            | * s . . . . . e *
            | * * * * * * * * *
        },
        items: [
            {
                id: "key",
                x: 3,
                y: 3,
                name: "Secret key",
                description: "What if this key opens a secret door?",
                useTimes: 1,
                value: 0,
                actions: {
                    [not(inventoryFull())] retrieveItem(key),
                    [] leave()
                }
            }
        ],
        entities: [
            {
                id: "door",
                x: 4,
                y: 1,
                name: "Secret door",
                description: "This door can only be opened with a secret key",
                direction: left,
                actions: {
                    [inventoryContains(key)] useItem(key),
                    [] leave()
                }
            }
        ]
    },
    {
        layout: {
            | * * * * * * * * * * *
            | * . . . . . . . . . *
            | * * * * * * * * * . *
            | * e . . . . . . . s *
            | * * * * * * * * * . *
            | x x x x x x x x * . *
            | * * * * * * * * * . *
            | * . . . . . . . . . *
            | * * * * * * * * * * *
        },
        items: [
            {
                id: "key",
                x: 1,
                y: 1,
                name: "Key to sturdy door",
                description: "You have proven worthy",
                useTimes: 1,
                value: 0,
                actions: {
                    [not(inventoryFull())] retrieveItem(key),
                    [] leave()
                }
            },
            {
                id: "sword",
                x: 1,
                y: 7,
                name: "Mighty sword",
                description: "Slayer of evil",
                useTimes: 3,
                value: 100,
                actions: {
                    [not(inventoryFull())] retrieveItem(sword),
                    [] leave()
                }
            }
        ],
        entities: [
            {
                id: "door",
                x: 8,
                y: 5,
                name: "Sturdy door",
                description: "I wonder what's behind it?",
                direction: right,
                actions: {
                    [inventoryContains(key)] useItem(key),
                    [] leave()
                }
            },
            {
                id: "devil",
                x: 6,
                y: 1,
                name: "Evil powers",
                description: "Certainly from hell",
                hp: 55,
                value: 10,
                actions: {
                    [inventoryContains(dagger)] decreaseHp(devil, dagger),
                    [inventoryContains(sword)] decreaseHp(devil, sword),
                    [] leave()
                }
            }
        ]
    }
]