// Phase 7 — `channel_info(channel_url)` via the new strawcore.
// Used by ChannelScreen (single-channel view) AND
// SubscriptionFeedViewModel (which fans out across all subscriptions).

use strawcore_core::youtube::channel::{channel_info as core_channel_info, ChannelInfo as CoreInfo};
use strawcore_core::youtube::linkhandler::channel as core_link;

use crate::error::StrawcoreError;
use crate::search::{from_core as search_from_core, SearchItem};

#[derive(Debug, Clone, uniffi::Record)]
pub struct ChannelInfo {
    pub id: String,
    pub name: String,
    pub avatar: Option<String>,
    pub banner: Option<String>,
    /// -1 = unknown / hidden by the channel.
    pub subscriber_count: i64,
    pub description: String,
    /// Latest videos from the channel (Videos tab, newest first).
    pub videos: Vec<SearchItem>,
}

#[uniffi::export(async_runtime = "tokio")]
pub async fn channel_info(input: String) -> Result<ChannelInfo, StrawcoreError> {
    log::info!("strawcore::channel_info input_len={}", input.len());
    crate::runtime::ensure_initialized();
    let identifier = resolve_channel_identifier(&input)?;
    let core = tokio::task::spawn_blocking(move || core_channel_info(identifier))
        .await
        .map_err(|e| StrawcoreError::Extractor {
            msg: format!("join: {e}"),
        })??;
    Ok(map_channel(core))
}

fn resolve_channel_identifier(
    input: &str,
) -> Result<core_link::ChannelIdentifier, StrawcoreError> {
    let trimmed = input.trim();
    // Bare channel ID — UC..., 24 chars.
    if trimmed.starts_with("UC") && trimmed.len() == 24 {
        return Ok(core_link::ChannelIdentifier::DirectId(trimmed.into()));
    }
    core_link::parse(trimmed).map_err(|e| StrawcoreError::Unsupported {
        detail: e.to_string(),
    })
}

fn map_channel(c: CoreInfo) -> ChannelInfo {
    let avatar = c.avatars.last().map(|i| i.url().to_string());
    let banner = c.banners.last().map(|i| i.url().to_string());
    let videos = c.recent_videos.into_iter().map(search_from_core).collect();
    ChannelInfo {
        id: c.channel_id,
        name: c.name,
        avatar,
        banner,
        subscriber_count: c.subscriber_count,
        description: c.description,
        videos,
    }
}