//! Pinned message management — maps to `message_pin` table.
//!
//! A channel can have multiple pinned messages with explicit ordering.
//! Unlike the `message.pinned` boolean (which just marks the row),
//! this table tracks *who* pinned, *when*, and the display *position*.

use chrono::{DateTime, Utc};
use serde::{Deserialize, Serialize};
use uuid::Uuid;

/// One pinned message entry. Ordered by `position` ascending.
#[derive(Debug, Clone, Serialize, Deserialize, sqlx::FromRow)]
pub struct MessagePin {
    pub id: Uuid,
    pub channel_id: Uuid,
    pub message_id: Uuid,
    /// Who pinned this message.
    pub pinned_by: Uuid,
    /// Display position in the pinned list (0 = top).
    pub position: i32,
    pub created_at: DateTime<Utc>,
}

/// Summary view returned by list-pins APIs (joined with message content).
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct PinDetail {
    #[serde(flatten)]
    pub pin: MessagePin,
    pub message_body: String,
    pub message_author_id: Uuid,
    pub message_created_at: DateTime<Utc>,
}

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

    #[test]
    fn test_pin_detail_serialize() {
        let pin = MessagePin {
            id: Uuid::now_v7(),
            channel_id: Uuid::now_v7(),
            message_id: Uuid::now_v7(),
            pinned_by: Uuid::now_v7(),
            position: 0,
            created_at: Utc::now(),
        };

        let detail = PinDetail {
            pin,
            message_body: "important announcement".to_string(),
            message_author_id: Uuid::now_v7(),
            message_created_at: Utc::now(),
        };

        let json = serde_json::to_value(&detail).unwrap();
        assert_eq!(json["position"], 0);
        assert_eq!(json["message_body"], "important announcement");
    }
}