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::IssueSubscriber;
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 subscribers to return (default: 50, max: 100)
    pub limit: Option<i64>,
    /// Number of subscribers to skip for pagination (default: 0)
    pub offset: Option<i64>,
}

/// List subscribers of an issue
///
/// Returns a paginated list of all users subscribed to the given issue.
/// Shows who receives notifications and their subscription reason (author, assignee, manual).
/// Requires read access to the issue.
#[utoipa::path(
    get,
    path = "/api/v1/workspaces/{workspace_name}/issues/{number}/subscribers",
    tag = "Issues",
    operation_id = "issueListSubscribers",
    params(PathParams, QueryParams),
    responses(
        (status = 200, description = "Subscribers listed successfully. Returns array of subscriber objects.", body = ApiResponse<Vec<IssueSubscriber>>),
        (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_subscribers(
    service: web::Data<AppService>,
    session: Session,
    path: web::Path<PathParams>,
    query: web::Query<QueryParams>,
) -> Result<HttpResponse, AppError> {
    let subscribers = service
        .issue
        .issue_subscribers(
            &session,
            &path.workspace_name,
            path.number,
            query.limit.unwrap_or(50),
            query.offset.unwrap_or(0),
        )
        .await?;
    Ok(HttpResponse::Ok().json(ApiResponse::new(subscribers)))
}

/// Subscribe to an issue
///
/// Subscribes the authenticated user to the given issue to receive notifications.
/// Requires read access to the issue.
///
/// Effects:
/// - User is added as a subscriber with "manual" reason
/// - User receives notifications for all issue activity
///
/// Returns the created subscription record.
#[utoipa::path(
    post,
    path = "/api/v1/workspaces/{workspace_name}/issues/{number}/subscribe",
    tag = "Issues",
    operation_id = "issueSubscribe",
    params(PathParams),
    responses(
        (status = 200, description = "Subscribed successfully. Returns the subscription record.", body = ApiResponse<IssueSubscriber>),
        (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 = 409, description = "Already subscribed to this issue", body = ApiErrorResponse),
        (status = 500, description = "Internal server error", body = ApiErrorResponse),
    ),
    security(
        ("session_cookie" = [])
    )
)]
pub async fn subscribe(
    service: web::Data<AppService>,
    session: Session,
    path: web::Path<PathParams>,
) -> Result<HttpResponse, AppError> {
    let sub = service
        .issue
        .issue_subscribe(&session, &path.workspace_name, path.number)
        .await?;
    Ok(HttpResponse::Ok().json(ApiResponse::new(sub)))
}

/// Unsubscribe from an issue
///
/// Removes the authenticated user's subscription to the given issue.
/// Stops all notifications for this issue.
///
/// Returns success message on completion.
#[utoipa::path(
    delete,
    path = "/api/v1/workspaces/{workspace_name}/issues/{number}/subscribe",
    tag = "Issues",
    operation_id = "issueUnsubscribe",
    params(PathParams),
    responses(
        (status = 200, description = "Unsubscribed successfully.", body = ApiResponse<String>),
        (status = 401, description = "Authentication required or session expired", body = ApiErrorResponse),
        (status = 404, description = "Not currently subscribed to this issue", body = ApiErrorResponse),
        (status = 500, description = "Internal server error", body = ApiErrorResponse),
    ),
    security(
        ("session_cookie" = [])
    )
)]
pub async fn unsubscribe(
    service: web::Data<AppService>,
    session: Session,
    path: web::Path<PathParams>,
) -> Result<HttpResponse, AppError> {
    service
        .issue
        .issue_unsubscribe(&session, &path.workspace_name, path.number)
        .await?;
    Ok(HttpResponse::Ok().json(ApiResponse::new("Unsubscribed".to_string())))
}

#[derive(Debug, Deserialize, utoipa::ToSchema)]
pub struct MuteIssueParams {
    /// Whether to mute (true) or unmute (false) notifications
    pub muted: bool,
}

/// Mute or unmute issue notifications
///
/// Mutes or unmutes notifications for the given issue without unsubscribing.
/// Requires an active subscription to the issue.
///
/// Returns success message on completion.
#[utoipa::path(
    put,
    path = "/api/v1/workspaces/{workspace_name}/issues/{number}/mute",
    tag = "Issues",
    operation_id = "issueMute",
    params(PathParams),
    request_body(
        content = MuteIssueParams,
        description = "Mute/unmute parameters",
        content_type = "application/json"
    ),
    responses(
        (status = 200, description = "Mute status updated successfully.", body = ApiResponse<String>),
        (status = 401, description = "Authentication required or session expired", body = ApiErrorResponse),
        (status = 404, description = "Not currently subscribed to this issue", body = ApiErrorResponse),
        (status = 500, description = "Internal server error", body = ApiErrorResponse),
    ),
    security(
        ("session_cookie" = [])
    )
)]
pub async fn mute(
    service: web::Data<AppService>,
    session: Session,
    path: web::Path<PathParams>,
    params: web::Json<MuteIssueParams>,
) -> Result<HttpResponse, AppError> {
    service
        .issue
        .issue_mute(&session, &path.workspace_name, path.number, params.muted)
        .await?;
    Ok(HttpResponse::Ok().json(ApiResponse::new("Mute status updated".to_string())))
}