//! Repository ports (traits)
//!
//! These traits define the interface for data persistence.
//! Implementations live in the infra layer.

use std::collections::HashMap;

use async_trait::async_trait;
use chrono::DateTime;
use chrono::Utc;
use uuid::Uuid;

use crate::entities::{Channel, ChannelConfigSnapshot, GeneratedSchedule, PlaybackRecord, ScheduleConfig, User};
use crate::errors::DomainResult;
use crate::value_objects::{BlockId, ChannelId, MediaItemId, UserId};

/// An in-app activity event stored in the database for the admin log view.
#[derive(Debug, Clone)]
pub struct ActivityEvent {
    pub id: Uuid,
    pub timestamp: DateTime<Utc>,
    pub event_type: String,
    pub detail: String,
    pub channel_id: Option<Uuid>,
}

/// Repository port for User persistence
#[async_trait]
pub trait UserRepository: Send + Sync {
    /// Find a user by their internal ID
    async fn find_by_id(&self, id: Uuid) -> DomainResult<Option<User>>;

    /// Find a user by their OIDC subject (used for authentication)
    async fn find_by_subject(&self, subject: &str) -> DomainResult<Option<User>>;

    /// Find a user by their email
    async fn find_by_email(&self, email: &str) -> DomainResult<Option<User>>;

    /// Save a new user or update an existing one
    async fn save(&self, user: &User) -> DomainResult<()>;

    /// Delete a user by their ID
    async fn delete(&self, id: Uuid) -> DomainResult<()>;

    /// Count total number of users (used for first-user admin promotion)
    async fn count_users(&self) -> DomainResult<u64>;
}

#[derive(Debug, Clone)]
pub struct ProviderConfigRow {
    pub provider_type: String,
    pub config_json: String,
    pub enabled: bool,
    pub updated_at: String,
}

#[async_trait]
pub trait ProviderConfigRepository: Send + Sync {
    async fn get_all(&self) -> DomainResult<Vec<ProviderConfigRow>>;
    async fn upsert(&self, row: &ProviderConfigRow) -> DomainResult<()>;
    async fn delete(&self, provider_type: &str) -> DomainResult<()>;
}

/// Repository port for `Channel` persistence.
#[async_trait]
pub trait ChannelRepository: Send + Sync {
    async fn find_by_id(&self, id: ChannelId) -> DomainResult<Option<Channel>>;
    async fn find_by_owner(&self, owner_id: UserId) -> DomainResult<Vec<Channel>>;
    async fn find_all(&self) -> DomainResult<Vec<Channel>>;
    async fn find_auto_schedule_enabled(&self) -> DomainResult<Vec<Channel>>;
    /// Insert or update a channel.
    async fn save(&self, channel: &Channel) -> DomainResult<()>;
    async fn delete(&self, id: ChannelId) -> DomainResult<()>;

    /// Snapshot the current config before saving a new one.
    /// version_num is computed by the infra layer as MAX(version_num)+1 inside a transaction.
    async fn save_config_snapshot(
        &self,
        channel_id: ChannelId,
        config: &ScheduleConfig,
        label: Option<String>,
    ) -> DomainResult<ChannelConfigSnapshot>;

    async fn list_config_snapshots(
        &self,
        channel_id: ChannelId,
    ) -> DomainResult<Vec<ChannelConfigSnapshot>>;

    async fn get_config_snapshot(
        &self,
        channel_id: ChannelId,
        snapshot_id: Uuid,
    ) -> DomainResult<Option<ChannelConfigSnapshot>>;

    async fn patch_config_snapshot_label(
        &self,
        channel_id: ChannelId,
        snapshot_id: Uuid,
        label: Option<String>,
    ) -> DomainResult<Option<ChannelConfigSnapshot>>;
}

/// Repository port for `GeneratedSchedule` and `PlaybackRecord` persistence.
#[async_trait]
pub trait ScheduleRepository: Send + Sync {
    /// Find the schedule whose `[valid_from, valid_until)` window contains `at`.
    async fn find_active(
        &self,
        channel_id: ChannelId,
        at: DateTime<Utc>,
    ) -> DomainResult<Option<GeneratedSchedule>>;

    /// Find the most recently generated schedule for a channel.
    /// Used to derive the next generation number.
    async fn find_latest(
        &self,
        channel_id: ChannelId,
    ) -> DomainResult<Option<GeneratedSchedule>>;

    /// Insert or replace a generated schedule.
    async fn save(&self, schedule: &GeneratedSchedule) -> DomainResult<()>;

    /// All playback records for a channel, used by the recycle policy engine.
    async fn find_playback_history(
        &self,
        channel_id: ChannelId,
    ) -> DomainResult<Vec<PlaybackRecord>>;

    async fn save_playback_record(&self, record: &PlaybackRecord) -> DomainResult<()>;

    /// Return the most recent slot per block_id across ALL schedules for a channel.
    /// Resilient to any single generation having empty slots for a block.
    async fn find_last_slot_per_block(
        &self,
        channel_id: ChannelId,
    ) -> DomainResult<HashMap<BlockId, MediaItemId>>;

    /// List all generated schedule headers for a channel, newest first.
    async fn list_schedule_history(
        &self,
        channel_id: ChannelId,
    ) -> DomainResult<Vec<GeneratedSchedule>>;

    /// Fetch a specific schedule with its slots, verifying channel ownership.
    async fn get_schedule_by_id(
        &self,
        channel_id: ChannelId,
        schedule_id: Uuid,
    ) -> DomainResult<Option<GeneratedSchedule>>;

    /// Delete all schedules with generation > target_generation for this channel.
    /// Also deletes matching playback_records (no DB cascade between those tables).
    /// scheduled_slots cascade via FK from generated_schedules.
    async fn delete_schedules_after(
        &self,
        channel_id: ChannelId,
        target_generation: u32,
    ) -> DomainResult<()>;
}

/// Repository port for activity log persistence.
#[async_trait]
pub trait ActivityLogRepository: Send + Sync {
    async fn log(
        &self,
        event_type: &str,
        detail: &str,
        channel_id: Option<Uuid>,
    ) -> DomainResult<()>;
    async fn recent(&self, limit: u32) -> DomainResult<Vec<ActivityEvent>>;
}

/// Repository port for transcode settings persistence.
#[async_trait]
pub trait TranscodeSettingsRepository: Send + Sync {
    /// Load the persisted cleanup TTL. Returns None if no row exists yet.
    async fn load_cleanup_ttl(&self) -> DomainResult<Option<u32>>;
    /// Persist the cleanup TTL (upsert — always row id=1).
    async fn save_cleanup_ttl(&self, hours: u32) -> DomainResult<()>;
}