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

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

#[derive(Debug, Deserialize, IntoParams)]
pub struct PrPath {
    /// Workspace name (unique identifier)
    pub workspace_name: String,
    /// Repository name (unique within the workspace)
    pub repo_name: String,
    /// PR number (unique within the repository)
    pub number: i64,
}

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

#[derive(Debug, Deserialize, IntoParams)]
pub struct QP {
    pub limit: Option<i64>,
    pub offset: Option<i64>,
}

/// List assignees of a PR
#[utoipa::path(
    get,
    path = "/api/v1/workspaces/{workspace_name}/repos/{repo_name}/prs/{number}/assignees",
    tag = "Pull Requests",
    operation_id = "prListAssignees",
    params(PrPath, QP),
    responses(
        (status = 200, description = "Assignees listed.", body = ApiResponse<Vec<PrAssignee>>),
        (status = 401, description = "Authentication required", body = ApiErrorResponse),
        (status = 404, description = "PR not found", body = ApiErrorResponse),
        (status = 500, description = "Internal server error", body = ApiErrorResponse),
    ),
    security(("session_cookie" = []))
)]
pub async fn list_assignees(
    service: web::Data<AppService>,
    session: Session,
    path: web::Path<PrPath>,
    query: web::Query<QP>,
) -> Result<HttpResponse, AppError> {
    let assignees = service
        .pr
        .pr_assignees(
            &session,
            &path.workspace_name,
            &path.repo_name,
            path.number,
            query.limit.unwrap_or(50),
            query.offset.unwrap_or(0),
        )
        .await?;
    Ok(HttpResponse::Ok().json(ApiResponse::new(assignees)))
}

/// Assign a user to a PR. Assignee is auto-subscribed.
#[utoipa::path(
    post,
    path = "/api/v1/workspaces/{workspace_name}/repos/{repo_name}/prs/{number}/assignees/{user_id}",
    tag = "Pull Requests",
    operation_id = "prAssign",
    params(UserPath),
    responses(
        (status = 201, description = "User assigned.", body = ApiResponse<PrAssignee>),
        (status = 401, description = "Authentication required", body = ApiErrorResponse),
        (status = 403, description = "Insufficient permissions", body = ApiErrorResponse),
        (status = 404, description = "PR not found", body = ApiErrorResponse),
        (status = 409, description = "User already assigned", body = ApiErrorResponse),
        (status = 500, description = "Internal server error", body = ApiErrorResponse),
    ),
    security(("session_cookie" = []))
)]
pub async fn assign_user(
    service: web::Data<AppService>,
    session: Session,
    path: web::Path<UserPath>,
) -> Result<HttpResponse, AppError> {
    let assignee = service
        .pr
        .pr_assign(
            &session,
            &path.workspace_name,
            &path.repo_name,
            path.number,
            path.user_id,
        )
        .await?;
    Ok(HttpResponse::Created().json(ApiResponse::new(assignee)))
}

/// Unassign a user from a PR
#[utoipa::path(
    delete,
    path = "/api/v1/workspaces/{workspace_name}/repos/{repo_name}/prs/{number}/assignees/{user_id}",
    tag = "Pull Requests",
    operation_id = "prUnassign",
    params(UserPath),
    responses(
        (status = 200, description = "User unassigned.", body = ApiResponse<String>),
        (status = 401, description = "Authentication required", body = ApiErrorResponse),
        (status = 403, description = "Insufficient permissions", body = ApiErrorResponse),
        (status = 404, description = "Assignee not found", body = ApiErrorResponse),
        (status = 500, description = "Internal server error", body = ApiErrorResponse),
    ),
    security(("session_cookie" = []))
)]
pub async fn unassign_user(
    service: web::Data<AppService>,
    session: Session,
    path: web::Path<UserPath>,
) -> Result<HttpResponse, AppError> {
    service
        .pr
        .pr_unassign(
            &session,
            &path.workspace_name,
            &path.repo_name,
            path.number,
            path.user_id,
        )
        .await?;
    Ok(HttpResponse::Ok().json(ApiResponse::new("User unassigned".to_string())))
}