use qr_core::qr::{QrCode, QrConfig, VersionMode};
use qr_core::version::EcLevel;
use serde::{Deserialize, Serialize};
use std::sync::Mutex;

/// QR 编码响应
#[derive(Debug, Serialize, Clone)]
struct QrResponse {
    svg: String,
    version: u8,
    size: u8,
    mask: u8,
}

/// 历史记录条目
#[derive(Debug, Serialize, Deserialize, Clone)]
struct HistoryEntry {
    id: String,
    mode: String,
    content: String,
    timestamp: u64,
}

/// 应用状态
struct AppState {
    history: Mutex<Vec<HistoryEntry>>,
}

/// 编码 QR 码，返回 SVG + 元信息
#[tauri::command]
fn encode_qr(text: String, level: String, margin: u8) -> Result<QrResponse, String> {
    let ec_level = match level.to_uppercase().as_str() {
        "L" => EcLevel::L,
        "M" => EcLevel::M,
        "Q" => EcLevel::Q,
        "H" => EcLevel::H,
        _ => return Err(format!("无效纠错级别: {}", level)),
    };

    let config = QrConfig {
        level: ec_level,
        version: VersionMode::Auto,
        margin,
    };

    let qr = QrCode::encode(&text, config).map_err(|e| format!("编码失败: {}", e))?;

    let svg = qr.to_svg();

    Ok(QrResponse {
        svg,
        version: qr.version.0,
        size: qr.size(),
        mask: qr.mask,
    })
}

/// 导出 PNG bytes
#[tauri::command]
fn export_png(text: String, level: String, margin: u8, module_size: u8) -> Result<Vec<u8>, String> {
    let ec_level = match level.to_uppercase().as_str() {
        "L" => EcLevel::L,
        "M" => EcLevel::M,
        "Q" => EcLevel::Q,
        "H" => EcLevel::H,
        _ => return Err(format!("无效纠错级别: {}", level)),
    };

    let config = QrConfig {
        level: ec_level,
        version: VersionMode::Auto,
        margin,
    };

    let qr = QrCode::encode(&text, config).map_err(|e| format!("编码失败: {}", e))?;

    Ok(qr.to_png_bytes(module_size))
}

/// 保存历史记录条目
#[tauri::command]
fn save_history(state: tauri::State<AppState>, entry: HistoryEntry) -> Result<(), String> {
    let mut history = state.history.lock().map_err(|e| e.to_string())?;
    history.push(entry);
    if history.len() > 50 {
        history.remove(0);
    }
    Ok(())
}

/// 加载全部历史记录
#[tauri::command]
fn load_history(state: tauri::State<AppState>) -> Result<Vec<HistoryEntry>, String> {
    let history = state.history.lock().map_err(|e| e.to_string())?;
    Ok(history.clone())
}

/// 清空历史记录
#[tauri::command]
fn clear_history(state: tauri::State<AppState>) -> Result<(), String> {
    let mut history = state.history.lock().map_err(|e| e.to_string())?;
    history.clear();
    Ok(())
}

#[cfg_attr(mobile, tauri::mobile_entry_point)]
pub fn run() {
    tauri::Builder::default()
        .plugin(tauri_plugin_store::Builder::new().build())
        .plugin(tauri_plugin_dialog::init())
        .plugin(tauri_plugin_clipboard_manager::init())
        .manage(AppState {
            history: Mutex::new(Vec::new()),
        })
        .invoke_handler(tauri::generate_handler![
            encode_qr,
            export_png,
            save_history,
            load_history,
            clear_history,
        ])
        .run(tauri::generate_context!())
        .expect("启动 QRGen GUI 失败");
}