use std::future::Future;

use axum::http::StatusCode;
use serde_json::json;
use spacetime_client::SpacetimeClientError;

use crate::{http_error::AppError, state::AppState};

pub(crate) const ASSET_OPERATION_POINTS_COST: u64 = 1;

/// 资产操作统一执行入口：业务层只声明操作类型与资源 ID，钱包扣退费由服务层收口。
pub(crate) async fn execute_billable_asset_operation<T, Fut>(
    state: &AppState,
    owner_user_id: &str,
    asset_kind: &str,
    asset_id: &str,
    operation: Fut,
) -> Result<T, AppError>
where
    Fut: Future<Output = Result<T, AppError>>,
{
    execute_billable_asset_operation_with_cost(
        state,
        owner_user_id,
        asset_kind,
        asset_id,
        ASSET_OPERATION_POINTS_COST,
        operation,
    )
    .await
}

/// 生图等特殊操作可声明独立泥点成本，避免修改全局资产操作默认价格。
pub(crate) async fn execute_billable_asset_operation_with_cost<T, Fut>(
    state: &AppState,
    owner_user_id: &str,
    asset_kind: &str,
    asset_id: &str,
    points_cost: u64,
    operation: Fut,
) -> Result<T, AppError>
where
    Fut: Future<Output = Result<T, AppError>>,
{
    let points_consumed =
        consume_asset_operation_points(state, owner_user_id, asset_kind, asset_id, points_cost)
            .await?;
    match operation.await {
        Ok(value) => Ok(value),
        Err(error) => {
            if points_consumed {
                refund_asset_operation_points(
                    state,
                    owner_user_id,
                    asset_kind,
                    asset_id,
                    points_cost,
                )
                .await;
            }
            Err(error)
        }
    }
}

/// 资产操作统一预扣泥点；扣费流水 ID 由业务资源 ID 参与构造，保证重试幂等。
async fn consume_asset_operation_points(
    state: &AppState,
    owner_user_id: &str,
    asset_kind: &str,
    asset_id: &str,
    points_cost: u64,
) -> Result<bool, AppError> {
    let ledger_id = format!(
        "asset_operation_consume:{}:{}:{}",
        owner_user_id, asset_kind, asset_id
    );
    match state
        .spacetime_client()
        .consume_profile_wallet_points(
            owner_user_id.to_string(),
            points_cost,
            ledger_id,
            current_utc_micros(),
        )
        .await
    {
        Ok(_) => Ok(true),
        Err(error) if should_skip_asset_operation_billing_for_connectivity(&error) => {
            // 中文注释：外部生图不应被 Maincloud 钱包短暂 503 阻断；此时跳过扣费，让业务链路继续，避免用户重复点击。
            tracing::warn!(
                owner_user_id,
                asset_kind,
                asset_id,
                error = %error,
                "资产操作泥点预扣因 SpacetimeDB 连接不可用而降级跳过"
            );
            Ok(false)
        }
        Err(error) => Err(map_asset_operation_wallet_error(error)),
    }
}

/// 外部生成或发布 mutation 失败后补偿退款；退款失败只记日志，避免覆盖原始业务错误。
async fn refund_asset_operation_points(
    state: &AppState,
    owner_user_id: &str,
    asset_kind: &str,
    asset_id: &str,
    points_cost: u64,
) {
    let ledger_id = format!(
        "asset_operation_refund:{}:{}:{}",
        owner_user_id, asset_kind, asset_id
    );
    if let Err(error) = state
        .spacetime_client()
        .refund_profile_wallet_points(
            owner_user_id.to_string(),
            points_cost,
            ledger_id,
            current_utc_micros(),
        )
        .await
    {
        tracing::error!(
            owner_user_id,
            asset_kind,
            asset_id,
            error = %error,
            "资产操作失败后的泥点退款失败"
        );
    }
}

pub(crate) fn map_asset_operation_wallet_error(error: SpacetimeClientError) -> AppError {
    let message = error.to_string();
    tracing::warn!(
        provider = "profile-wallet",
        error = %message,
        "资产操作泥点预扣失败"
    );
    let status = match &error {
        SpacetimeClientError::Procedure(message) if message.contains("泥点余额不足") => {
            StatusCode::CONFLICT
        }
        _ => StatusCode::BAD_GATEWAY,
    };

    AppError::from_status(status).with_details(json!({
        "provider": "profile-wallet",
        "message": message,
    }))
}

pub(crate) fn should_skip_asset_operation_billing_for_connectivity(
    error: &SpacetimeClientError,
) -> bool {
    match error {
        SpacetimeClientError::ConnectDropped | SpacetimeClientError::Timeout => true,
        SpacetimeClientError::Build(message)
        | SpacetimeClientError::Procedure(message)
        | SpacetimeClientError::Runtime(message) => {
            message.contains("503")
                || message.contains("Service Unavailable")
                || message.contains("Failed to connect")
                || message.contains("WebSocket")
                || message.contains("No such procedure")
                || message.contains("连接已断开")
                || message.contains("连接在返回结果前已断开")
        }
    }
}

fn current_utc_micros() -> i64 {
    time::OffsetDateTime::now_utc().unix_timestamp_nanos() as i64 / 1_000
}

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

    #[test]
    fn asset_operation_billing_skips_spacetime_connectivity_errors() {
        assert_eq!(ASSET_OPERATION_POINTS_COST, 1);
        assert!(should_skip_asset_operation_billing_for_connectivity(
            &SpacetimeClientError::ConnectDropped
        ));
        assert!(should_skip_asset_operation_billing_for_connectivity(
            &SpacetimeClientError::Runtime(
                "Failed to connect: HTTP error: 503 Service Unavailable".to_string(),
            ),
        ));
        assert!(should_skip_asset_operation_billing_for_connectivity(
            &SpacetimeClientError::Procedure(
                "No such procedure: consume_profile_wallet_points_and_return".to_string(),
            ),
        ));
        assert!(!should_skip_asset_operation_billing_for_connectivity(
            &SpacetimeClientError::Procedure("泥点余额不足".to_string()),
        ));
    }
}