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

use crate::api::response::{ApiErrorResponse, ApiResponse};
use crate::error::AppError;
use crate::models::issues::IssueAssignee;
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 assign
    pub user_id: uuid::Uuid,
}

/// Assign a user to an issue
///
/// Assigns a workspace member to the given issue.
/// Requires write access to the issue (author or workspace member).
///
/// Effects:
/// - User is assigned to the issue
/// - Assignee is automatically subscribed to the issue
/// - Issue assignee count is incremented
///
/// Returns the created assignment record.
#[utoipa::path(
    post,
    path = "/api/v1/workspaces/{workspace_name}/issues/{number}/assignees/{user_id}",
    tag = "Issues",
    operation_id = "issueAssign",
    params(PathParams),
    responses(
        (status = 201, description = "User assigned successfully. Returns the created assignment record.", body = ApiResponse<IssueAssignee>),
        (status = 401, description = "Authentication required or session expired", body = ApiErrorResponse),
        (status = 403, description = "Insufficient permissions to edit this issue", body = ApiErrorResponse),
        (status = 404, description = "Issue or user not found", body = ApiErrorResponse),
        (status = 409, description = "User is already assigned to this issue", body = ApiErrorResponse),
        (status = 500, description = "Internal server error", body = ApiErrorResponse),
    ),
    security(
        ("session_cookie" = [])
    )
)]
pub async fn assign_issue(
    service: web::Data<AppService>,
    session: Session,
    path: web::Path<PathParams>,
) -> Result<HttpResponse, AppError> {
    let assignee = service
        .issue
        .issue_assign(&session, &path.workspace_name, path.number, path.user_id)
        .await?;
    Ok(HttpResponse::Created().json(ApiResponse::new(assignee)))
}