//! Provider part of the Market API
use ya_client_model::market::{
    Agreement, AgreementOperationEvent, NewOffer, NewProposal, Offer, Proposal, ProviderEvent,
    Reason, MARKET_API_PATH,
};

use crate::{web::default_on_timeout, web::WebClient, web::WebInterface, Result};
use chrono::{DateTime, TimeZone};
use std::fmt::Display;

/// Bindings for Provider part of the Market API.
#[derive(Clone)]
pub struct MarketProviderApi {
    client: WebClient,
}

impl WebInterface for MarketProviderApi {
    const API_URL_ENV_VAR: &'static str = crate::market::MARKET_URL_ENV_VAR;
    const API_SUFFIX: &'static str = MARKET_API_PATH;

    fn from_client(client: WebClient) -> Self {
        MarketProviderApi { client }
    }
}

impl MarketProviderApi {
    /// Publish Provider’s service capabilities (`Offer`) on the market to declare an
    /// interest in Demands meeting specified criteria.
    pub async fn subscribe(&self, offer: &NewOffer) -> Result<String> {
        self.client.post("offers").send_json(&offer).json().await
    }

    /// Fetches all active Offers which have been published by the Provider.
    pub async fn get_offers(&self) -> Result<Vec<Offer>> {
        self.client.get("offers").send().json().await
    }

    /// Stop subscription by invalidating a previously published Offer.
    ///
    /// Stop receiving Proposals.
    /// **Note**: this will terminate all pending `collect_demands` calls on this subscription.
    /// This implies, that client code should not `unsubscribe_offer` before it has received
    /// all expected/useful inputs from `collect_demands`.
    pub async fn unsubscribe(&self, subscription_id: &str) -> Result<()> {
        let url = url_format!("offers/{subscription_id}", subscription_id);
        self.client.delete(&url).send().json().await
    }

    /// Get events which have arrived from the market in response to the Offer
    /// published by the Provider via  [`subscribe`](#method.subscribe).
    /// Returns collection of at most `max_events` `ProviderEvents` or times out.
    ///
    /// This is a blocking operation. It will not return until there is at
    /// least one new event.
    ///
    /// Returns Proposal related events:
    ///
    /// * `ProposalEvent` - Indicates that there is new Demand Proposal for
    /// this Offer.
    ///
    /// * `ProposalRejectedEvent` - Indicates that the Requestor has rejected
    ///   our previous Proposal related to this Offer. This effectively ends a
    ///   Negotiation chain - it explicitly indicates that the sender will not
    ///   create another counter-Proposal.
    ///
    /// * `AgreementEvent` - Indicates that the Requestor is accepting our
    ///   previous Proposal and ask for our approval of the Agreement.
    ///
    /// * `PropertyQueryEvent` - not supported yet.
    ///
    /// **Note**: When `collectOffers` is waiting, simultaneous call to
    /// `unsubscribeDemand` on the same `subscriptionId` should result in
    /// "Subscription does not exist" error returned from `collectOffers`.
    ///
    /// **Note**: Specification requires this endpoint to support list of
    /// specific Proposal Ids to listen for messages related only to specific
    /// Proposals. This is not covered yet.
    #[rustfmt::skip]
    pub async fn collect(
        &self,
        subscription_id: &str,
        timeout: Option<f32>,
        max_events: Option<i32>,
    ) -> Result<Vec<ProviderEvent>> {
        let url = url_format!(
            "offers/{subscription_id}/events",
            subscription_id,
            #[query] timeout,
            #[query] max_events,
        );

        self.client.get(&url).send().json().await.or_else(default_on_timeout)
    }

    /// Fetches Proposal (Demand) with given id.
    pub async fn get_proposal(&self, subscription_id: &str, proposal_id: &str) -> Result<Proposal> {
        let url = url_format!(
            "offers/{subscription_id}/proposals/{proposal_id}",
            subscription_id,
            proposal_id,
        );
        self.client.get(&url).send().json().await
    }

    /// Rejects Proposal (Demand).
    ///
    /// Effectively ends a Negotiation chain - it explicitly indicates that
    /// the sender will not create another counter-Proposal.
    pub async fn reject_proposal(
        &self,
        subscription_id: &str,
        proposal_id: &str,
        reason: &Option<Reason>,
    ) -> Result<()> {
        let url = url_format!(
            "offers/{subscription_id}/proposals/{proposal_id}/reject",
            subscription_id,
            proposal_id,
        );
        self.client.post(&url).send_json(&reason).json().await
    }

    /// Responds with a bespoke Offer to received Demand.
    /// Creates and sends a modified version of original Offer (a
    /// counter-proposal) adjusted to previously received Proposal (ie. Demand).
    /// Changes Proposal state to `Draft`. Returns created Proposal id.
    pub async fn counter_proposal(
        &self,
        offer_proposal: &NewProposal,
        subscription_id: &str,
        proposal_id: &str,
    ) -> Result<String> {
        let url = url_format!(
            "offers/{subscription_id}/proposals/{proposal_id}",
            subscription_id,
            proposal_id,
        );
        self.client
            .post(&url)
            .send_json(&offer_proposal)
            .json()
            .await
    }

    /// Approves Agreement proposed by the Reqestor.
    ///
    /// This is a blocking operation. The call may be aborted by Provider caller
    /// code. After the call is aborted or timed out, another `approve_agreement`
    /// call can be raised on the same `agreement_id`.
    ///
    /// It returns one of the following options:
    ///
    /// * `Ok` Agreement approved. Indicates that the approved Agreement has been
    ///  successfully delivered to the Requestor and acknowledged.
    ///    - The Requestor side has been notified about the Provider’s commitment.
    ///    - The Provider is now ready to accept a request to start an Activity.
    ///    - The Requestor’s corresponding `wait_for_approval` call returns `Ok`
    ///    (Approved) **after** this endpoint on the Provider side.
    ///
    /// * `Err` - Indicates that Agreement is not approved.
    ///   - `408` Agreement not approved within given timeout. Try again.
    ///   - `410` Agreement approval failed permanently.
    /// Attached `ErrorMessage` contains further details:
    ///   - `Rejected` - Indicates that the Provider himself has already
    ///     called `reject_agreement`.
    ///   - `Cancelled` - Indicates that before Provider approved this Agreement,
    ///     the Requestor has called `cancel_agreement`, thus invalidating the
    ///     Agreement. The Provider may attempt to return to the Negotiation phase
    ///     by sending a new Proposal.
    ///   - `Expired` - Indicates that Agreement validity period elapsed and it was
    ///     not approved, rejected nor cancelled.
    ///   - `Terminated` - Indicates that Agreement is already terminated.
    #[rustfmt::skip]
    pub async fn approve_agreement(
        &self,
        agreement_id: &str,
        app_session_id: Option<String>,
        timeout: Option<f32>,
    ) -> Result<()> {
        let url = url_format!(
            "agreements/{agreement_id}/approve",
            agreement_id,
            #[query] app_session_id,
            #[query] timeout,
        );
        self.client.post(&url).send().json().await
    }

    /// Rejects Agreement proposed by the Requestor.
    ///
    /// The Requestor side is notified about the Provider’s decision to reject
    /// a negotiated agreement. This effectively stops the Agreement handshake.
    ///
    /// **Note**: Mutually exclusive with `approve_agreement`.
    pub async fn reject_agreement(
        &self,
        agreement_id: &str,
        reason: &Option<Reason>,
    ) -> Result<()> {
        let url = url_format!("agreements/{agreement_id}/reject", agreement_id);
        self.client.post(&url).send_json(&reason).json().await
    }

    /// Terminates approved Agreement.
    pub async fn terminate_agreement(
        &self,
        agreement_id: &str,
        reason: &Option<Reason>,
    ) -> Result<()> {
        let url = url_format!("agreements/{agreement_id}/terminate", agreement_id);
        self.client.post(&url).send_json(&reason).json().await
    }

    /// Fetches agreement with given agreement id.
    pub async fn get_agreement(&self, agreement_id: &str) -> Result<Agreement> {
        let url = url_format!("agreements/{agreement_id}", agreement_id);
        self.client.get(&url).send().json().await
    }

    /// Collects events related to an Agreement.
    ///
    /// This is a blocking operation. It will not return until there is
    /// at least one new event. All events are appearing on both sides equally.
    ///
    /// Returns Agreement related events:
    ///
    /// * `AgreementApprovedEvent` - Indicates that the Agreement has been
    ///   approved by the Provider.
    ///     - The Provider is now ready to accept a request to start an
    ///       Activity as described in the negotiated agreement.
    ///     - The Providers’s corresponding `approveAgreement` call
    ///       returns `Approved` after this event is emitted.
    ///
    /// * `AgreementRejectedEvent` - Indicates that the Provider has called
    ///   `rejectAgreement`, which effectively stops the Agreement handshake.
    ///   The Requestor may attempt to return to the Negotiation phase by
    ///   sending a new Proposal.
    ///
    /// * `AgreementCancelledEvent` - Indicates that the Requestor has called
    ///   `cancelAgreement`, which effectively stops the Agreement handshake.
    ///
    /// * `AgreementTerminatedEvent` - Indicates that the Agreement has been
    ///   terminated by specified party (contains signature).
    #[rustfmt::skip]
    pub async fn collect_agreement_events<Tz>(
        &self,
        timeout: Option<f32>,
        after_timestamp: Option<&DateTime<Tz>>,
        max_events: Option<i32>,
        app_session_id: Option<String>,
    ) -> Result<Vec<AgreementOperationEvent>>
        where
            Tz: TimeZone,
            Tz::Offset: Display,
    {
        let after_timestamp = after_timestamp.map(|dt| dt.to_rfc3339());
        let url = url_format!(
            "agreementEvents",
            #[query] timeout,
            #[query] after_timestamp,
            #[query] max_events,
            #[query] app_session_id,
        );
        self.client.get(&url).send().json().await.or_else(default_on_timeout)
    }
}