use actix_web::{HttpResponse, web};
use serde::Deserialize;
use utoipa::IntoParams;

use crate::api::response::{ApiErrorResponse, ApiResponse};
use crate::error::AppError;
use crate::service::AppService;
use crate::session::Session;

#[derive(Debug, Deserialize, IntoParams)]
pub struct PathParams {
    /// Workspace name (unique identifier)
    pub workspace_name: String,
    /// Issue number (unique within the workspace)
    pub number: i64,
    /// User ID (UUID) to unassign
    pub user_id: uuid::Uuid,
}

/// Unassign a user from an issue
///
/// Removes a user from the issue's assignee list.
/// Requires write access to the issue (author or workspace member).
///
/// Effects:
/// - User is removed from the issue's assignees
/// - Issue assignee count is decremented
///
/// Returns success message on completion.
#[utoipa::path(
    delete,
    path = "/api/v1/workspaces/{workspace_name}/issues/{number}/assignees/{user_id}",
    tag = "Issues",
    operation_id = "issueUnassign",
    params(PathParams),
    responses(
        (status = 200, description = "User unassigned successfully.", body = ApiResponse<String>),
        (status = 401, description = "Authentication required or session expired", body = ApiErrorResponse),
        (status = 403, description = "Insufficient permissions to edit this issue", body = ApiErrorResponse),
        (status = 404, description = "User is not assigned to this issue or not found", body = ApiErrorResponse),
        (status = 500, description = "Internal server error", body = ApiErrorResponse),
    ),
    security(
        ("session_cookie" = [])
    )
)]
pub async fn unassign_issue(
    service: web::Data<AppService>,
    session: Session,
    path: web::Path<PathParams>,
) -> Result<HttpResponse, AppError> {
    service
        .issue
        .issue_unassign(&session, &path.workspace_name, path.number, path.user_id)
        .await?;
    Ok(HttpResponse::Ok().json(ApiResponse::new("User unassigned".to_string())))
}