interprex 6.0.0

use async_trait::async_trait;

use super::{
    BranchUpdateError, BranchUpdateObservation, ChangeRequest, ChangeRequestHead,
    ChangeRequestNumber, CheckOutcome, CheckRun, FindingResolution, FindingResolutionReply,
    ProviderTextRecord, ReviewCommentId, ReviewPublicationKey, ReviewRequestTarget,
    ReviewRequestTargetInspection, ReviewSubmission, ReviewThreadId, ReviewerApplication,
};
use crate::{Repository, Result};

/// Optional provider capability for observing and updating change-request
/// branches.
///
/// A provider can implement [`CodeReviewsProvider`] without implementing this
/// trait. Only providers with a native exact-head update operation implement
/// both.
#[async_trait]
pub trait BranchUpdatesProvider: Send + Sync {
    /// Reads current branch freshness for the change request's exact revisions.
    ///
    /// The returned revisions are the exact endpoints used for the freshness
    /// result. The applied source configuration and mergeability are separate
    /// facts. This operation does not decide whether an update should occur.
    ///
    /// # Errors
    ///
    /// Returns [`crate::ProviderError::NotFound`] when the change request or a
    /// compared revision is absent, [`crate::ProviderError::Unrepresentable`]
    /// when the provider reports a comparison this interface cannot express,
    /// and [`crate::ProviderError::External`] when the provider read fails.
    async fn branch_update(
        &self,
        repository: &Repository,
        number: ChangeRequestNumber,
    ) -> Result<BranchUpdateObservation>;

    /// Requests the provider's native branch update only if the change
    /// request still has `expected_head_sha`.
    ///
    /// The provider applies its current target branch to the exact observed
    /// head. The operation neither chooses when an update is appropriate nor
    /// substitutes a newer head.
    ///
    /// # Errors
    ///
    /// Returns [`BranchUpdateError::StaleHead`] when the current head differs
    /// from `expected_head_sha`,
    /// [`crate::ProviderError::NotFound`] when the change request is absent,
    /// [`crate::ProviderError::InvalidInput`] when `expected_head_sha` is empty,
    /// and [`crate::ProviderError::External`] when the provider refuses or
    /// cannot complete the update. Provider errors are retained inside
    /// [`BranchUpdateError::Provider`].
    async fn update_change_request_branch(
        &self,
        repository: &Repository,
        number: ChangeRequestNumber,
        expected_head_sha: &str,
    ) -> std::result::Result<(), BranchUpdateError>;
}

#[async_trait]
pub trait CodeReviewsProvider: Send + Sync {
    /// Reads one complete observation of the change request.
    ///
    /// Each collection of [`super::ReviewComment`] values follows one stable,
    /// total provider order from earliest to latest, including when the
    /// provider returned several pages. A caller resolving competing comments
    /// chooses the first valid comment in this order. It does not compare
    /// [`ReviewCommentId`] values, whose representation has no ordering meaning.
    async fn change_request(
        &self,
        repository: &Repository,
        number: ChangeRequestNumber,
    ) -> Result<ChangeRequest>;
    /// Reads the number of every open change request in `repository` that
    /// proposes `head`.
    ///
    /// A change request belongs to the repository it targets, and its head
    /// branch can live in a fork of that repository, so `repository` and
    /// `head.repository()` are stated separately and can differ. A caller
    /// working from a git checkout names the repository the change request
    /// targets and the branch it pushed, wherever that branch lives.
    ///
    /// A branch can be proposed by more than one open change request against
    /// different bases, so every match is returned; choosing among them is the
    /// caller's policy, made from `ChangeRequest::base_branch` after reading
    /// each candidate through `change_request`. Order carries no policy
    /// meaning, and an empty result means no open change request in
    /// `repository` proposes that head.
    ///
    /// A match proposes exactly `head`: both the repository holding the branch
    /// and the branch itself, so heads differing only by repository name are
    /// different heads. `ChangeRequest::head` reports the same fact for a
    /// change request read by number.
    async fn open_change_requests(
        &self,
        repository: &Repository,
        head: &ChangeRequestHead,
    ) -> Result<Vec<ChangeRequestNumber>>;
    async fn resolve_thread(
        &self,
        repository: &Repository,
        number: ChangeRequestNumber,
        thread_id: &ReviewThreadId,
    ) -> Result<()>;
    /// Records why a finding is complete, records its assessed severity and
    /// marks its platform thread resolved.
    ///
    /// `reply` contains validated visible explanatory text. Providers may add
    /// their own visible or machine-readable representation around it.
    /// Providers whose platforms require more than one request can return an
    /// error after a partial write; a later observation preserves the platform
    /// thread state and any valid resolution record independently.
    ///
    /// Repeating an already recorded resolution does not add another reply. If
    /// that record exists while the platform thread is open, the repeated call
    /// only resolves the thread.
    async fn resolve_finding(
        &self,
        repository: &Repository,
        number: ChangeRequestNumber,
        thread_id: &ReviewThreadId,
        resolution: FindingResolution,
        reply: &FindingResolutionReply,
    ) -> Result<()>;
    /// Asks the platform to add each target to the outstanding reviewer set.
    ///
    /// A target already present remains one request, so repeating the same call
    /// reaches the same observable state.
    ///
    /// Success reports the platform's acceptance, nothing more: a platform can
    /// accept a request and record nothing, as GitHub does for a bot it cannot
    /// assign. Whether a request stands recorded is a fact of the outstanding
    /// reviewer set, read through [`Self::change_request`]; what a target
    /// names is answered before requesting by
    /// [`ReviewTargetsProvider::inspect_review_request_target`], where a
    /// provider offers it.
    async fn request_reviewers(
        &self,
        repository: &Repository,
        number: ChangeRequestNumber,
        reviewers: &[ReviewRequestTarget],
    ) -> Result<()>;
    async fn mark_ready(&self, repository: &Repository, number: ChangeRequestNumber) -> Result<()>;
    /// Reads the current checks on one commit, completely paginated.
    ///
    /// A check name identifies no more than one run only within a run of
    /// checks that the platform grouped together, which GitHub calls a check
    /// suite. One commit can carry several runs of the same name, published by
    /// several applications or by one application whose workflow was
    /// triggered more than once, and every one of them is returned. Deciding
    /// which of them answers for that name is the caller's, using `via_app`,
    /// the status and the completion time; Interprex discards none of them.
    /// Within one such group a rerun does replace the run it repeated, so no
    /// superseded run is reported.
    ///
    /// A check that has not concluded is returned with the platform's own
    /// status rather than omitted, so a caller can tell a missing check from a
    /// running or a stalled one. Collection order carries no meaning.
    ///
    /// A platform can report less than it holds: GitHub answers from at most
    /// the 1,000 most recent check suites on a commit and gives no signal that
    /// it stopped there, so a commit past that limit is reported short.
    ///
    /// Which of these checks a merge requires comes from the repository's
    /// rulesets, and what a failing required check means for the change
    /// request is the caller's policy. Interprex performs neither step.
    ///
    /// A platform that also keeps a separate legacy commit-status mechanism,
    /// as GitHub does, does not report those statuses here.
    async fn checks(&self, repository: &Repository, head_sha: &str) -> Result<Vec<CheckRun>>;
    async fn publish_check(
        &self,
        repository: &Repository,
        app_name: &str,
        outcome: &CheckOutcome,
    ) -> Result<()>;
}

/// Optional provider capability for inspecting review-request targets.
///
/// This trait is separate from [`CodeReviewsProvider`] so providers that
/// cannot inspect target identities do not advertise the operation and
/// existing implementations remain source compatible.
#[async_trait]
pub trait ReviewTargetsProvider: Send + Sync {
    /// Inspects one target using the credentials and provider context for
    /// `repository`.
    ///
    /// The result reports the identity and category the provider actually
    /// observed. A matching result is not an assignability check and does not
    /// promise that a later request will be recorded or delivered. Callers
    /// that need to validate several targets can inspect them individually
    /// before persisting any of them.
    async fn inspect_review_request_target(
        &self,
        repository: &Repository,
        target: &ReviewRequestTarget,
    ) -> Result<ReviewRequestTargetInspection>;
}

/// Optional provider capability for embedding structured records in provider
/// text and reading them back.
///
/// This trait owns only the text carrier. [`ProviderTextRecord::value`] has no
/// provider-defined meaning, and callers decide which namespaces, record names
/// and protocol versions they understand.
pub trait TextRecordsProvider: Send + Sync {
    /// Returns `text` with one hidden carrier containing `record`.
    ///
    /// The supplied text remains visible without alteration when the provider
    /// renders the returned value. The carrier itself may be visible through a
    /// raw-text interface. A valid [`ProviderTextRecord`] is always encodable.
    fn embed_record(&self, text: &str, record: &ProviderTextRecord) -> String;

    /// Extracts valid records from `text` in source order.
    ///
    /// Malformed carriers are ordinary text and are omitted. Records with a
    /// namespace, name or positive protocol version unknown to the caller are
    /// returned unchanged.
    fn extract_records(&self, text: &str) -> Vec<ProviderTextRecord>;
}

/// Optional provider capability for creating unanchored change-request
/// comments.
///
/// This trait is separate from [`CodeReviewsProvider`] so an implementation
/// can support code-review observation without supporting comment creation.
#[async_trait]
pub trait ChangeRequestCommentsProvider: Send + Sync {
    /// Creates exactly one unanchored comment with `body` and returns the
    /// provider identifier assigned to that comment.
    ///
    /// The provider receives the body exactly as supplied. A provider that
    /// rejects the body returns [`crate::ProviderError::InvalidInput`]; a
    /// transport or platform failure returns
    /// [`crate::ProviderError::External`].
    async fn create_unanchored_comment(
        &self,
        repository: &Repository,
        number: ChangeRequestNumber,
        body: &str,
    ) -> Result<ReviewCommentId>;
}

/// Optional provider capability for resolving reviewer applications.
///
/// This trait is separate from [`CodeReviewsProvider`] because a provider can
/// observe and request reviewers without supporting application lookup.
#[async_trait]
pub trait ReviewerApplicationsProvider: Send + Sync {
    /// Resolves `slug`, using the credentials selected for `repository`, to
    /// the application and bot actor the provider observes.
    ///
    /// The result contains the provider application's identifier, slug and
    /// name beside the bot's identifier, login and actor kind. It does not say
    /// that the application is installed for `repository`, that the bot can
    /// appear in the platform's outstanding reviewer set, that a review will
    /// arrive, or that a delivered review will attribute the application
    /// separately from its bot author.
    ///
    /// # Errors
    ///
    /// Returns [`crate::ProviderError::NotFound`] when either identity cannot
    /// be observed, [`crate::ProviderError::Unrepresentable`] when observed
    /// provider data cannot construct a [`ReviewerApplication`], and
    /// [`crate::ProviderError::External`] when the provider operation fails.
    async fn resolve_reviewer_application(
        &self,
        repository: &Repository,
        slug: &str,
    ) -> Result<ReviewerApplication>;
}

/// Optional provider capability for publishing complete application-authored
/// reviews.
///
/// This trait is separate from [`CodeReviewsProvider`] so a provider can
/// observe reviews without supporting their creation.
#[async_trait]
pub trait ReviewPublishingProvider: Send + Sync {
    /// Publishes `submission` as `reviewer` and returns the provider's review
    /// identifier.
    ///
    /// The publication key is scoped to `repository`, `number`, and reviewer
    /// identity. Repeating a key with the same reviewer and submission returns
    /// the original [`ReviewId`](super::ReviewId) without creating another
    /// review. Reviewer identity is the pair of provider application ID and
    /// bot actor ID; application names and slugs and bot logins do not affect
    /// identity. Another reviewer identity can use the same key independently.
    /// Reusing a key with a different submission under the same reviewer
    /// identity returns [`crate::ProviderError::InvalidInput`].
    ///
    /// The provider publishes against the supplied revision exactly. It does
    /// not replace that commit with the change request's current head. An
    /// adapter may create a provider-specific draft while recovering from
    /// retries. It creates that draft with the complete summary and findings
    /// in one provider request. A hidden record written with the draft retains
    /// the publication key, a digest of the complete submission, and the
    /// intended final disposition; the provider preserves that record when it
    /// submits the review. The caller neither creates an empty draft nor adds
    /// individual findings to one.
    ///
    /// Two concurrent calls using a previously unseen key need not collapse
    /// into one review. A caller that can publish the same planned review from
    /// several tasks serializes those calls.
    ///
    /// # Errors
    ///
    /// Returns [`crate::ProviderError::MissingCredential`] when no credential
    /// is available for `reviewer`, and [`crate::ProviderError::Configuration`]
    /// when the selected credential belongs to a different provider
    /// application ID. Returns [`crate::ProviderError::NotFound`] when the
    /// change request or exact revision does not exist,
    /// [`crate::ProviderError::InvalidInput`] when the publication key already
    /// identifies a different submission for the same reviewer, when the
    /// summary uses metadata reserved by the adapter, or when the provider
    /// rejects a supplied review field as invalid, and
    /// [`crate::ProviderError::External`] when transport or provider behavior
    /// prevents publication or leaves a result the adapter cannot reconcile.
    async fn publish_review(
        &self,
        repository: &Repository,
        number: ChangeRequestNumber,
        reviewer: &ReviewerApplication,
        submission: &ReviewSubmission,
    ) -> Result<super::ReviewId>;

    /// Recovers a complete review publication using only its retained key.
    ///
    /// The adapter considers only records whose provider application ID and bot
    /// actor ID match `reviewer`; records from other reviewers are ignored.
    /// For an exact-identity record, the adapter validates the record version,
    /// key, retained submission digest, and intended disposition. It trusts
    /// those fields because the provider created the review summary, hidden
    /// record, and every inline finding atomically. It does not fetch inline
    /// comments to reconstruct a lost [`ReviewSubmission`] or recompute its
    /// digest.
    ///
    /// When the matching provider review is pending, the adapter submits it
    /// with the retained disposition. When it is already submitted, the
    /// adapter adopts it and returns its identifier. When no exact-identity
    /// record carries `key` for this change request, the method returns `None`.
    ///
    /// Reviewer identity is the provider application ID and bot actor ID pair,
    /// independent of mutable application names, slugs, and bot logins.
    ///
    /// # Errors
    ///
    /// Returns [`crate::ProviderError::MissingCredential`] when no credential
    /// is available for `reviewer`, and [`crate::ProviderError::Configuration`]
    /// when the selected credential belongs to a different provider
    /// application ID. Returns [`crate::ProviderError::NotFound`] when the
    /// change request does not exist, and [`crate::ProviderError::External`]
    /// when transport fails or when duplicate, malformed, incomplete, or
    /// contradictory exact-identity records prevent reconciliation. A review
    /// from the exact identity with a missing record is also external when it
    /// could be the result of an accepted publication request.
    async fn resume_review_publication(
        &self,
        repository: &Repository,
        number: ChangeRequestNumber,
        reviewer: &ReviewerApplication,
        key: &ReviewPublicationKey,
    ) -> Result<Option<super::ReviewId>>;
}