// Copyright 2020 The Matrix.org Foundation C.I.C.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

use matrix_sdk_base::crypto::{AcceptSettings, CancelInfo, Emoji, ReadOnlyDevice, Sas as BaseSas};
use ruma::{events::key::verification::cancel::CancelCode, UserId};

use crate::{error::Result, Client};

/// An object controlling the short auth string verification flow.
#[derive(Debug, Clone)]
pub struct SasVerification {
    pub(crate) inner: BaseSas,
    pub(crate) client: Client,
}

impl SasVerification {
    /// Accept the interactive verification flow.
    pub async fn accept(&self) -> Result<()> {
        self.accept_with_settings(Default::default()).await
    }

    /// Accept the interactive verification flow with specific settings.
    ///
    /// # Arguments
    ///
    /// * `settings` - specific customizations to the verification flow.
    ///
    /// # Examples
    ///
    /// ```no_run
    /// # use matrix_sdk::Client;
    /// # use futures::executor::block_on;
    /// # use url::Url;
    /// # use ruma::user_id;
    /// use matrix_sdk::{
    ///     encryption::verification::{AcceptSettings, SasVerification},
    ///     ruma::events::key::verification::ShortAuthenticationString,
    /// };
    ///
    /// # let flow_id = "someID";
    /// # let user_id = user_id!("@alice:example");
    /// # block_on(async {
    /// # let homeserver = Url::parse("http://example.com")?;
    /// # let client = Client::new(homeserver).await?;
    /// let sas = client
    ///     .encryption()
    ///     .get_verification(&user_id, flow_id)
    ///     .await
    ///     .and_then(|v| v.sas());
    ///
    /// if let Some(sas) = sas {
    ///     let only_decimal = AcceptSettings::with_allowed_methods(vec![
    ///         ShortAuthenticationString::Decimal,
    ///     ]);
    ///
    ///     sas.accept_with_settings(only_decimal).await?;
    /// }
    /// # anyhow::Ok(()) });
    /// ```
    pub async fn accept_with_settings(&self, settings: AcceptSettings) -> Result<()> {
        if let Some(request) = self.inner.accept_with_settings(settings) {
            self.client.send_verification_request(request).await?;
        }
        Ok(())
    }

    /// Confirm that the short auth strings match on both sides.
    pub async fn confirm(&self) -> Result<()> {
        let (requests, signature) = self.inner.confirm().await?;

        for request in requests {
            self.client.send_verification_request(request).await?;
        }

        if let Some(s) = signature {
            self.client.send(s, None).await?;
        }

        Ok(())
    }

    /// Cancel the interactive verification flow because the short auth strings
    /// didn't match on both sides.
    pub async fn mismatch(&self) -> Result<()> {
        if let Some(request) = self.inner.cancel_with_code(CancelCode::MismatchedSas) {
            self.client.send_verification_request(request).await?;
        }

        Ok(())
    }

    /// Cancel the interactive verification flow.
    pub async fn cancel(&self) -> Result<()> {
        if let Some(request) = self.inner.cancel() {
            self.client.send_verification_request(request).await?;
        }

        Ok(())
    }

    /// Get the emoji version of the short auth string.
    ///
    /// # Examples
    ///
    /// ```no_run
    /// # use matrix_sdk::Client;
    /// # use futures::executor::block_on;
    /// # use url::Url;
    /// # use ruma::user_id;
    /// use matrix_sdk::{
    ///     encryption::verification::{AcceptSettings, SasVerification},
    ///     ruma::events::key::verification::ShortAuthenticationString,
    /// };
    ///
    /// # let flow_id = "someID";
    /// # let user_id = user_id!("@alice:example");
    /// # block_on(async {
    /// # let homeserver = Url::parse("http://example.com")?;
    /// # let client = Client::new(homeserver).await?;
    /// let sas_verification = client
    ///     .encryption()
    ///     .get_verification(&user_id, flow_id)
    ///     .await
    ///     .and_then(|v| v.sas());
    ///
    /// if let Some(emojis) = sas_verification.and_then(|s| s.emoji()) {
    ///     let emoji_string = emojis
    ///         .iter()
    ///         .map(|e| format!("{:^12}", e.symbol))
    ///         .collect::<Vec<_>>()
    ///         .join("");
    ///
    ///     let description = emojis
    ///         .iter()
    ///         .map(|e| format!("{:^12}", e.description))
    ///         .collect::<Vec<_>>()
    ///         .join("");
    ///
    ///     println!("Do the emojis match?\n{emoji_string}\n{description}");
    /// }
    /// # anyhow::Ok(()) });
    /// ```
    pub fn emoji(&self) -> Option<[Emoji; 7]> {
        self.inner.emoji()
    }

    /// Get the decimal version of the short auth string.
    pub fn decimals(&self) -> Option<(u16, u16, u16)> {
        self.inner.decimals()
    }

    /// Does this verification flow support emoji for the short authentication
    /// string.
    pub fn supports_emoji(&self) -> bool {
        self.inner.supports_emoji()
    }

    /// Is the verification process done.
    pub fn is_done(&self) -> bool {
        self.inner.is_done()
    }

    /// Are we in a state where we can show the short auth string.
    pub fn can_be_presented(&self) -> bool {
        self.inner.can_be_presented()
    }

    /// Did we initiate the verification flow.
    pub fn we_started(&self) -> bool {
        self.inner.we_started()
    }

    /// Get info about the cancellation if the verification flow has been
    /// cancelled.
    pub fn cancel_info(&self) -> Option<CancelInfo> {
        self.inner.cancel_info()
    }

    /// Is the verification process canceled.
    pub fn is_cancelled(&self) -> bool {
        self.inner.is_cancelled()
    }

    /// Get the other users device that we're verifying.
    pub fn other_device(&self) -> &ReadOnlyDevice {
        self.inner.other_device()
    }

    /// Did this verification flow start from a verification request.
    pub fn started_from_request(&self) -> bool {
        self.inner.started_from_request()
    }

    /// Is this a verification that is veryfying one of our own devices.
    pub fn is_self_verification(&self) -> bool {
        self.inner.is_self_verification()
    }

    /// Get our own user id.
    pub fn own_user_id(&self) -> &UserId {
        self.inner.user_id()
    }

    /// Get the user id of the other user participating in this verification
    /// flow.
    pub fn other_user_id(&self) -> &UserId {
        self.inner.other_user_id()
    }
}