pub enum TransactionType {
    Batch(BatchTransaction),
    Normal(Transaction),
}

impl TransactionType {
    pub fn from(b: mongodb::bson::Document) -> Self {
        if let Ok(kind) = b.get_str("kind") {
            if kind == "batch" {
                return Self::Batch(BatchTransaction::from(b));
            }
        }
        Self::Normal(Transaction::from(b))
    }
}

pub struct Transaction {
    pub uuid: String,
    pub item: String,
    pub variant: String,
    pub price: Price,
    pub origin: String,
    pub timestamp: i64,
}

impl Transaction {
    pub fn new(item: &str, variant: &str, price: Price, origin: &str) -> Self {
        Self {
            uuid: uuid::Uuid::new_v4().to_string(),
            item: item.to_string(),
            variant: variant.to_string(),
            price,
            origin: origin.to_string(),
            timestamp: chrono::Utc::now().timestamp(),
        }
    }

    pub fn as_doc(&self) -> mongodb::bson::Document {
        mongodb::bson::doc! {
            "_id": &self.uuid,
            "item": &self.item,
            "variant": &self.variant,
            "price": self.price.as_bson(),
            "origin": &self.origin,
            "timestamp": self.timestamp
        }
    }

    fn from(b: mongodb::bson::Document) -> Self {
        let uuid = b.get_str("oid").unwrap().to_string();
        let item = b.get_str("item").unwrap().to_string();
        let variant = b.get_str("variant").unwrap().to_string();
        let origin = b.get_str("origin").unwrap().to_string();
        let timestamp = b.get_i64("timestamp").unwrap();
        let price = Price::from(b);
        Self {
            uuid,
            item,
            variant,
            price,
            origin,
            timestamp,
        }
    }
}

pub struct BatchTransaction {
    pub uuid: String,
    pub transactions: Vec<String>,
}

impl BatchTransaction {
    pub fn new(transactions: Vec<String>) -> Self {
        Self {
            uuid: uuid::Uuid::new_v4().to_string(),
            transactions,
        }
    }

    pub fn as_doc(&self) -> mongodb::bson::Document {
        mongodb::bson::doc! {
            "_id": &self.uuid,
            "kind": "batch",
            "transactions": &self.transactions
        }
    }

    fn from(b: mongodb::bson::Document) -> Self {
        let uuid = b.get_str("_id").unwrap().to_string();
        let transactions = b
            .get_array("transactions")
            .unwrap()
            .into_iter()
            .map(|x| x.as_str().unwrap().to_string())
            .collect();
        Self { uuid, transactions }
    }
}

#[derive(Debug, Clone)]
pub struct Price {
    pub value: f64,
    pub currency: String,
}

impl Price {
    pub fn new(value: f64, currency: &str) -> Self {
        Self {
            value,
            currency: currency.to_string(),
        }
    }

    fn parse(price: &str) -> Option<Self> {
        let (value, currency) = price.split_once(' ')?;

        Some(Self {
            value: value.parse().ok()?,
            currency: currency.to_string(),
        })
    }

    pub fn as_bson(&self) -> mongodb::bson::Bson {
        mongodb::bson::bson!({
            "value": self.value,
            "currency": self.currency.clone()
        })
    }
}

impl From<mongodb::bson::Document> for Price {
    fn from(value: mongodb::bson::Document) -> Self {
        Self {
            value: value.get_f64("value").unwrap(),
            currency: value.get_str("currency").unwrap().to_string(),
        }
    }
}

impl TryFrom<String> for Price {
    type Error = ();

    fn try_from(value: String) -> Result<Self, Self::Error> {
        Self::parse(&value).ok_or(())
    }
}