<?php

namespace App\Models;

use App\Models\Concerns\Reportable;
use App\Tables\Changeset;
use MightyPork\Exceptions\NotApplicableException;

/**
 * Change proposal
 *
 * @property int $id
 * @property \Carbon\Carbon $created_at
 * @property \Carbon\Carbon $updated_at
 * @property int $table_id
 * @property int $revision_id
 * @property int $author_id
 * @property string $note
 * @property Proposal $changes - JSONB
 * @property-read User $author
 * @property-read Table $table
 * @property-read Revision $revision
 */
class Proposal extends BaseModel
{
    use Reportable;
    protected $guarded = [];

    protected $touches = ['author', 'table'];

    /** Authoring user */
    public function author()
    {
        return $this->belongsTo(User::class, 'author_id');
    }

    /** Target revision */
    public function revision()
    {
        return $this->belongsTo(Revision::class);
    }

    /** Target table (that this was submitted to) */
    public function table()
    {
        return $this->belongsTo(Table::class);
    }

    public function getChangesAttribute($value)
    {
        $changeset = Changeset::fromObject(fromJSON($value));
        $changeset->revision = $this->revision;
        $changeset->table = $this->table;
        $changeset->note = $this->note;

        return $changeset;
    }

    public function setChangesAttribute($value)
    {
        if ($value instanceof Changeset) {
            $this->attributes['changes'] = toJSON($value->toObject());
        } else {
            throw new NotApplicableException("Only a Changeset may be set to Proposal->changes");
        }
    }

    /**
     * Create a new Proposal instance wrapping this changeset,
     * owned by the currently logged in User. The created instance
     * is NOT saved yet.
     *
     * @param Changeset $changeset - changeset to hydrate the proposal with
     * @return Proposal
     */
    public static function fromChangeset(Changeset $changeset)
    {
        if (!$changeset->hasAnyChanges()) {
            throw new NotApplicableException('No changes to propose.');
        }

        if ($changeset->note == null) {
            throw new NotApplicableException('Proposal note must be filled.');
        }

        if ($changeset->table == null || !$changeset->table instanceof Table) {
            throw new NotApplicableException('Table not assigned to Changeset');
        }

        if ($changeset->revision == null || !$changeset->revision instanceof Revision) {
            throw new NotApplicableException('Revision not assigned to Changeset');
        }

        return new Proposal([
            // relations
            'table_id' => $changeset->table->getKey(),
            'revision_id' => $changeset->revision->getKey(),
            'author_id' => \Auth::user()->getKey(),
            // the proposal info
            'note' => $changeset->note,
            'changes' => $changeset->toObject(),
        ]);
    }
}