//! Stable status codes for the official-resource to localized-release flow.
//!
//! The codes describe observable lifecycle state. They are deliberately
//! separate from `BAT-ERR-*`: an error code explains why an operation failed,
//! while a flow status code explains what a caller can do next.

use serde::{Deserialize, Serialize};

/// Stable status code shared by Rust reports and read-only RPC data.
#[derive(Debug, Clone, Copy, PartialEq, Eq, Serialize, Deserialize)]
pub enum ReleaseFlowStatusCode {
    /// No published official release is currently available.
    #[serde(rename = "official.unavailable")]
    OfficialUnavailable,
    /// The producer is discovering remote and local official-resource state.
    #[serde(rename = "official.checking")]
    OfficialChecking,
    /// The producer determined that a new or repaired official release is needed.
    #[serde(rename = "official.update_available")]
    OfficialUpdateAvailable,
    /// Official resources are being downloaded or reused into staging.
    #[serde(rename = "official.downloading")]
    OfficialDownloading,
    /// Downloaded official resources are being verified.
    #[serde(rename = "official.validating")]
    OfficialValidating,
    /// A verified official release is being staged or atomically published.
    #[serde(rename = "official.publishing")]
    OfficialPublishing,
    /// A verified official release has been published.
    #[serde(rename = "official.published")]
    OfficialPublished,
    /// The published official release already matches the observed remote state.
    #[serde(rename = "official.up_to_date")]
    OfficialUpToDate,
    /// Launcher/server-info has advanced before required CDN resources are readable.
    #[serde(rename = "official.waiting_for_resources")]
    OfficialWaitingForResources,
    /// Official-resource production failed before a publishable state was reached.
    #[serde(rename = "official.failed")]
    OfficialFailed,
    /// Parsing is blocked because there is no published official release.
    #[serde(rename = "parse.blocked_official")]
    ParseBlockedOfficial,
    /// A published official release exists but parse cache is not present yet.
    #[serde(rename = "parse.pending")]
    ParsePending,
    /// Parse cache or TextUnit index generation is running.
    #[serde(rename = "parse.running")]
    ParseRunning,
    /// Parse cache and TextUnit indexes are present without recorded parse failures.
    #[serde(rename = "parse.completed")]
    ParseCompleted,
    /// Parse cache exists but contains parser or extraction failures.
    #[serde(rename = "parse.completed_with_errors")]
    ParseCompletedWithErrors,
    /// Translation worker integration is not available for the observed release.
    #[serde(rename = "translation.unavailable")]
    TranslationUnavailable,
    /// Translation handoff files are being prepared from the official change set.
    #[serde(rename = "translation.handoff_preparing")]
    TranslationHandoffPreparing,
    /// Translation tasks have been queued to local offline handoff files.
    #[serde(rename = "translation.queued_offline")]
    TranslationQueuedOffline,
    /// Human proofreading is in progress for the observed localized release.
    #[serde(rename = "translation.manual_proofreading")]
    TranslationManualProofreading,
    /// Localized publication is blocked because there is no official release.
    #[serde(rename = "localized.blocked_official")]
    LocalizedBlockedOfficial,
    /// The current official release has no matching localized publication yet.
    #[serde(rename = "localized.pending")]
    LocalizedPending,
    /// A localized state exists but it does not match the current official release.
    #[serde(rename = "localized.stale")]
    LocalizedStale,
    /// A localized release is published and matches the current official release.
    #[serde(rename = "localized.published")]
    LocalizedPublished,
    /// Distribution cannot serve a usable release for the observed channel.
    #[serde(rename = "distribution.blocked")]
    DistributionBlocked,
    /// Distribution can serve the published release.
    #[serde(rename = "distribution.ready")]
    DistributionReady,
}

impl ReleaseFlowStatusCode {
    /// Returns the stable wire label.
    pub const fn as_str(self) -> &'static str {
        match self {
            Self::OfficialUnavailable => "official.unavailable",
            Self::OfficialChecking => "official.checking",
            Self::OfficialUpdateAvailable => "official.update_available",
            Self::OfficialDownloading => "official.downloading",
            Self::OfficialValidating => "official.validating",
            Self::OfficialPublishing => "official.publishing",
            Self::OfficialPublished => "official.published",
            Self::OfficialUpToDate => "official.up_to_date",
            Self::OfficialWaitingForResources => "official.waiting_for_resources",
            Self::OfficialFailed => "official.failed",
            Self::ParseBlockedOfficial => "parse.blocked_official",
            Self::ParsePending => "parse.pending",
            Self::ParseRunning => "parse.running",
            Self::ParseCompleted => "parse.completed",
            Self::ParseCompletedWithErrors => "parse.completed_with_errors",
            Self::TranslationUnavailable => "translation.unavailable",
            Self::TranslationHandoffPreparing => "translation.handoff_preparing",
            Self::TranslationQueuedOffline => "translation.queued_offline",
            Self::TranslationManualProofreading => "translation.manual_proofreading",
            Self::LocalizedBlockedOfficial => "localized.blocked_official",
            Self::LocalizedPending => "localized.pending",
            Self::LocalizedStale => "localized.stale",
            Self::LocalizedPublished => "localized.published",
            Self::DistributionBlocked => "distribution.blocked",
            Self::DistributionReady => "distribution.ready",
        }
    }

    /// Returns the short status value used alongside `status_code` in RPC
    /// payloads. This keeps existing human-facing labels independent from the
    /// namespaced wire code.
    pub const fn status(self) -> &'static str {
        match self {
            Self::OfficialUnavailable => "unavailable",
            Self::OfficialChecking => "checking",
            Self::OfficialUpdateAvailable => "update_available",
            Self::OfficialDownloading => "downloading",
            Self::OfficialValidating => "validating",
            Self::OfficialPublishing => "publishing",
            Self::OfficialPublished => "published",
            Self::OfficialUpToDate => "up_to_date",
            Self::OfficialWaitingForResources => "waiting_for_resources",
            Self::OfficialFailed => "failed",
            Self::ParseBlockedOfficial => "blocked_official",
            Self::ParsePending => "pending",
            Self::ParseRunning => "running",
            Self::ParseCompleted => "completed",
            Self::ParseCompletedWithErrors => "completed_with_errors",
            Self::TranslationUnavailable => "unavailable",
            Self::TranslationHandoffPreparing => "handoff_preparing",
            Self::TranslationQueuedOffline => "queued_offline",
            Self::TranslationManualProofreading => "manual_proofreading",
            Self::LocalizedBlockedOfficial => "blocked_official",
            Self::LocalizedPending => "pending",
            Self::LocalizedStale => "stale",
            Self::LocalizedPublished => "published",
            Self::DistributionBlocked => "blocked",
            Self::DistributionReady => "ready",
        }
    }

    /// Parses a status code read from a persisted daemon/RPC snapshot.
    fn parse_wire_code(code: &str) -> Option<Self> {
        Some(match code {
            "official.unavailable" => Self::OfficialUnavailable,
            "official.checking" => Self::OfficialChecking,
            "official.update_available" => Self::OfficialUpdateAvailable,
            "official.downloading" => Self::OfficialDownloading,
            "official.validating" => Self::OfficialValidating,
            "official.publishing" => Self::OfficialPublishing,
            "official.published" => Self::OfficialPublished,
            "official.up_to_date" => Self::OfficialUpToDate,
            "official.waiting_for_resources" => Self::OfficialWaitingForResources,
            "official.failed" => Self::OfficialFailed,
            "parse.blocked_official" => Self::ParseBlockedOfficial,
            "parse.pending" => Self::ParsePending,
            "parse.running" => Self::ParseRunning,
            "parse.completed" => Self::ParseCompleted,
            "parse.completed_with_errors" => Self::ParseCompletedWithErrors,
            "translation.unavailable" => Self::TranslationUnavailable,
            "translation.handoff_preparing" => Self::TranslationHandoffPreparing,
            "translation.queued_offline" => Self::TranslationQueuedOffline,
            "translation.manual_proofreading" => Self::TranslationManualProofreading,
            "localized.blocked_official" => Self::LocalizedBlockedOfficial,
            "localized.pending" => Self::LocalizedPending,
            "localized.stale" => Self::LocalizedStale,
            "localized.published" => Self::LocalizedPublished,
            "distribution.blocked" => Self::DistributionBlocked,
            "distribution.ready" => Self::DistributionReady,
            _ => return None,
        })
    }

    /// Returns the broad flow phase represented by this code.
    pub const fn phase(self) -> &'static str {
        match self {
            Self::OfficialUnavailable
            | Self::OfficialChecking
            | Self::OfficialUpdateAvailable
            | Self::OfficialDownloading
            | Self::OfficialValidating
            | Self::OfficialPublishing
            | Self::OfficialPublished
            | Self::OfficialUpToDate
            | Self::OfficialWaitingForResources
            | Self::OfficialFailed => "official_sync",
            Self::ParseBlockedOfficial
            | Self::ParsePending
            | Self::ParseRunning
            | Self::ParseCompleted
            | Self::ParseCompletedWithErrors => "parse",
            Self::TranslationUnavailable
            | Self::TranslationHandoffPreparing
            | Self::TranslationQueuedOffline
            | Self::TranslationManualProofreading => "translation",
            Self::LocalizedBlockedOfficial
            | Self::LocalizedPending
            | Self::LocalizedStale
            | Self::LocalizedPublished => "localized_publish",
            Self::DistributionBlocked | Self::DistributionReady => "distribution",
        }
    }

    /// Returns whether the state is stable for the current observation.
    pub const fn terminal(self) -> bool {
        !matches!(
            self,
            Self::OfficialChecking
                | Self::OfficialDownloading
                | Self::OfficialValidating
                | Self::OfficialPublishing
                | Self::ParseRunning
                | Self::TranslationHandoffPreparing
        )
    }

    /// Returns whether the producer may retry the operation automatically.
    pub const fn retryable(self) -> bool {
        matches!(
            self,
            Self::OfficialWaitingForResources
                | Self::OfficialFailed
                | Self::ParsePending
                | Self::ParseCompletedWithErrors
        )
    }

    /// Maps an existing official update result to the stable flow code.
    pub fn from_update_status(status: &str) -> Self {
        match status {
            "would_download" => Self::OfficialUpdateAvailable,
            "waiting_for_official_resources" => Self::OfficialWaitingForResources,
            "downloaded" => Self::OfficialPublished,
            "up_to_date" => Self::OfficialUpToDate,
            _ => Self::OfficialFailed,
        }
    }

    /// Maps an existing progress stage to the stable flow code.
    pub fn from_progress_stage(stage: &str) -> Self {
        match stage {
            "download" => Self::OfficialDownloading,
            "audit" | "snapshot" => Self::OfficialValidating,
            "publish" | "launcher-bootstrap" => Self::OfficialPublishing,
            "parse" => Self::ParseRunning,
            "changes" => Self::TranslationHandoffPreparing,
            "finish" => Self::OfficialPublished,
            _ => Self::OfficialChecking,
        }
    }
}

impl std::str::FromStr for ReleaseFlowStatusCode {
    type Err = ();

    fn from_str(code: &str) -> Result<Self, Self::Err> {
        Self::parse_wire_code(code).ok_or(())
    }
}

#[cfg(test)]
mod tests {
    use super::ReleaseFlowStatusCode;

    #[test]
    fn status_codes_are_stable_and_namespaced() {
        let codes = [
            ReleaseFlowStatusCode::OfficialUnavailable,
            ReleaseFlowStatusCode::OfficialChecking,
            ReleaseFlowStatusCode::OfficialUpdateAvailable,
            ReleaseFlowStatusCode::OfficialDownloading,
            ReleaseFlowStatusCode::OfficialValidating,
            ReleaseFlowStatusCode::OfficialPublishing,
            ReleaseFlowStatusCode::OfficialPublished,
            ReleaseFlowStatusCode::OfficialUpToDate,
            ReleaseFlowStatusCode::OfficialWaitingForResources,
            ReleaseFlowStatusCode::OfficialFailed,
            ReleaseFlowStatusCode::ParseBlockedOfficial,
            ReleaseFlowStatusCode::ParsePending,
            ReleaseFlowStatusCode::ParseRunning,
            ReleaseFlowStatusCode::ParseCompleted,
            ReleaseFlowStatusCode::ParseCompletedWithErrors,
            ReleaseFlowStatusCode::TranslationUnavailable,
            ReleaseFlowStatusCode::TranslationHandoffPreparing,
            ReleaseFlowStatusCode::TranslationQueuedOffline,
            ReleaseFlowStatusCode::TranslationManualProofreading,
            ReleaseFlowStatusCode::LocalizedBlockedOfficial,
            ReleaseFlowStatusCode::LocalizedPending,
            ReleaseFlowStatusCode::LocalizedStale,
            ReleaseFlowStatusCode::LocalizedPublished,
            ReleaseFlowStatusCode::DistributionBlocked,
            ReleaseFlowStatusCode::DistributionReady,
        ];
        let labels = codes.iter().map(|code| code.as_str()).collect::<Vec<_>>();
        let unique = labels.iter().collect::<std::collections::BTreeSet<_>>();
        assert_eq!(labels.len(), unique.len());
        assert!(labels.iter().all(|label| label.contains('.')));
    }

    #[test]
    fn status_codes_round_trip_through_from_str() {
        let code = ReleaseFlowStatusCode::LocalizedPublished;
        assert_eq!(code.as_str().parse::<ReleaseFlowStatusCode>(), Ok(code));
        assert!("unknown.status".parse::<ReleaseFlowStatusCode>().is_err());
    }
}