package com.hithomelabs.cftunnels.Entity;

import jakarta.persistence.*;
import lombok.AllArgsConstructor;
import lombok.Getter;
import lombok.NoArgsConstructor;
import lombok.Setter;

import java.util.UUID;

/**
 * JPA Entity representing a mapping change request in the approval workflow.
 * 
 * <p>This entity tracks requests to add or modify tunnel ingress mappings.
 * It implements an approval workflow where:</p>
 * <ul>
 *   <li>Users create requests (status: PENDING)</li>
 *   <li>Approvers review and approve/reject (status: APPROVED/REJECTED)</li>
 * </ul>
 * 
 * <p><b>Database Table:</b> {@code requests}</p>
 * 
 * <p><b>Workflow:</b></p>
 * <pre>
 * 1. User submits mapping request via REST API
 * 2. Request is created with PENDING status
 * 3. APPROVER role reviews the request
 * 4. If approved: mapping is applied to Cloudflare tunnel
 * 5. If rejected: request is marked REJECTED
 * </pre>
 * 
 * @see Mapping
 * @see User
 * @see RequestStatus
 */
@Entity
@Getter
@Setter
@NoArgsConstructor
@AllArgsConstructor
@Table(name = "requests")
public class Request {

    /**
     * Unique identifier for this request (auto-generated UUID).
     */
    @Id
    @GeneratedValue
    @Column(columnDefinition = "uuid", unique = true, nullable = false)
    private UUID id;

    /**
     * The mapping configuration being requested.
     * 
     * <p>This is a one-to-one relationship - each request
     * contains exactly one mapping configuration.</p>
     * 
     * @see Mapping
     */
    @OneToOne
    @JoinColumn(name = "mapping_id", unique = true, nullable = false)
    private Mapping mapping;

    /**
     * User who created this request.
     * 
     * <p>This field is required and tracks accountability.</p>
     * 
     * @see User
     */
    @ManyToOne
    @JoinColumn(name = "created_by", nullable = false)
    private User createdBy;

    /**
     * User who approved or rejected this request.
     * 
     * <p>This is null until the request is processed.</p>
     * 
     * @see User
     */
    @ManyToOne
    @JoinColumn(name = "accepted_by")
    private User acceptedBy;

    /**
     * Status of the mapping request in the workflow.
     * 
     * @see RequestStatus
     */
    public enum RequestStatus {
        /**
         * Request is waiting for approval.
         */
        PENDING,

        /**
         * Request has been approved.
         * The mapping should now be applied to the tunnel.
         */
        APPROVED,

        /**
         * Request has been rejected.
         * No changes will be made to the tunnel.
         */
        REJECTED
    }

    /**
     * Current status of this request.
     * 
     * <p>Initially set to PENDING when created.</p>
     * 
     * @see RequestStatus
     */
    @Enumerated(EnumType.STRING)
    @Column(length = 10, nullable = false)
    private RequestStatus status;
}