use serde::{Deserialize, Serialize};
use std::sync::Mutex;
use tauri::{AppHandle, Emitter, Manager};
use uuid::Uuid;

#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct DownloadRecord {
    pub id: String,
    pub url: String,
    pub filename: String,
    pub status: String,
    pub saved_to_library: bool,
    pub created_at: i64,
}

#[derive(Default)]
pub struct DownloadState {
    pub records: Mutex<Vec<DownloadRecord>>,
}

#[tauri::command]
pub fn downloads_list(app: AppHandle) -> Result<Vec<DownloadRecord>, String> {
    let state = app.state::<DownloadState>();
    let records = state.records.lock().map_err(|_| "download lock poisoned")?;
    Ok(records.clone())
}

#[tauri::command]
pub fn downloads_clear_completed(app: AppHandle) -> Result<(), String> {
    let state = app.state::<DownloadState>();
    let mut records = state.records.lock().map_err(|_| "download lock poisoned")?;
    records.retain(|r| r.status == "active");
    Ok(())
}

#[tauri::command]
pub async fn download_to_library(app: AppHandle, url: String) -> Result<crate::library::LibraryItem, String> {
    let filename = url.split('/').last().unwrap_or("download").to_string();
    let record = DownloadRecord {
        id: Uuid::new_v4().to_string(),
        url: url.clone(),
        filename: filename.clone(),
        status: "active".to_string(),
        saved_to_library: true,
        created_at: chrono::Utc::now().timestamp(),
    };
    {
        let state = app.state::<DownloadState>();
        let mut records = state.records.lock().map_err(|_| "download lock poisoned")?;
        records.push(record.clone());
    }
    let _ = app.emit("downloads://update", &record);
    let item = crate::library::library_add_item(app.clone(), url, Some(record.url.clone()), Some(filename)).await?;
    {
        let state = app.state::<DownloadState>();
        let mut records = state.records.lock().map_err(|_| "download lock poisoned")?;
        if let Some(r) = records.iter_mut().find(|r| r.id == record.id) {
            r.status = "complete".to_string();
        }
    }
    let _ = app.emit("downloads://complete", &record.id);
    Ok(item)
}

#[tauri::command]
pub fn web_clip_page(url: String, title: String) -> DownloadRecord {
    DownloadRecord {
        id: Uuid::new_v4().to_string(),
        url,
        filename: title,
        status: "clipped".to_string(),
        saved_to_library: false,
        created_at: chrono::Utc::now().timestamp(),
    }
}