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::IssueLabelRelation;
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,
}

#[derive(Debug, Deserialize, IntoParams)]
pub struct QueryParams {
    /// Maximum number of label relations to return (default: 50, max: 100)
    pub limit: Option<i64>,
    /// Number of label relations to skip for pagination (default: 0)
    pub offset: Option<i64>,
}

/// List labels assigned to an issue
///
/// Returns a paginated list of all label relations for the given issue.
/// Shows which labels are attached to the issue, with assignment metadata.
/// Requires read access to the issue.
#[utoipa::path(
    get,
    path = "/api/v1/workspaces/{workspace_name}/issues/{number}/labels",
    tag = "Issues",
    operation_id = "issueListLabelRelations",
    params(PathParams, QueryParams),
    responses(
        (status = 200, description = "Label relations listed successfully. Returns array of label relation objects with metadata.", body = ApiResponse<Vec<IssueLabelRelation>>),
        (status = 401, description = "Authentication required or session expired", body = ApiErrorResponse),
        (status = 403, description = "Insufficient permissions to view this issue", body = ApiErrorResponse),
        (status = 404, description = "Issue not found", body = ApiErrorResponse),
        (status = 500, description = "Internal server error", body = ApiErrorResponse),
    ),
    security(
        ("session_cookie" = [])
    )
)]
pub async fn list_issue_labels(
    service: web::Data<AppService>,
    session: Session,
    path: web::Path<PathParams>,
    query: web::Query<QueryParams>,
) -> Result<HttpResponse, AppError> {
    let rels = service
        .issue
        .issue_label_relations(
            &session,
            &path.workspace_name,
            path.number,
            query.limit.unwrap_or(50),
            query.offset.unwrap_or(0),
        )
        .await?;
    Ok(HttpResponse::Ok().json(ApiResponse::new(rels)))
}