preparing for proposal composition

app/Http/Controllers/TableController.php

@@ -5,6 +5,7 @@ namespace App\Http\Controllers;
 use App\Models\Revision;
 use App\Models\Table;
 use App\Models\User;
+use App\Tables\Changeset;
 use App\Tables\Column;
 use App\Tables\ColumnNumerator;
 use App\Tables\CStructArrayExporter;
@@ -57,22 +58,29 @@ class TableController extends Controller
     public function draftChange(Request $request, User $user, string $table)
     {
         /** @var Table $tableModel */
-        $tableModel = $user->tables()->with('revision')->where('name', $table)->first();
+        $tableModel = $user->tables()->where('name', $table)->first();
         if ($tableModel === null) abort(404, "No such table.");
 
-        $revision = $tableModel->revision;
+        $session_key = "proposal_{$tableModel->id}";
 
-        $columns = Column::columnsFromJson($revision->columns);
+        /** @var Changeset $changeset */
+        $changeset = $request->session()->remember($session_key, function () use ($tableModel) {
+            $changeset = new Changeset();
+            $changeset->table = $tableModel;
+            $changeset->revision = $tableModel->revision;
+            return $changeset;
+        });
 
+        $revision = $changeset->revision;
+        $columns = Column::columnsFromJson($revision->columns);
         $rows = $revision->rowsData($columns)->paginate(25, []);
 
-        // TODO instantiate changeset and store it in session
+        return view('table.propose', [
-
-        return view('table.view', [
             'table' => $tableModel,
             'revision' => $revision,
             'columns' => $columns,
             'rows' => $rows,
+            'changeset' => $changeset,
         ]);
     }
 

app/Models/Proposal.php

@@ -3,6 +3,8 @@
 namespace App\Models;
 
 use App\Models\Concerns\Reportable;
+use App\Tables\Changeset;
+use MightyPork\Exceptions\NotApplicableException;
 
 /**
  * Change proposal
@@ -14,7 +16,7 @@ use App\Models\Concerns\Reportable;
  * @property int $revision_id
  * @property int $author_id
  * @property string $note
- * @property object $changes - JSONB
+ * @property Proposal $changes - JSONB
  * @property-read User $author
  * @property-read Table $table
  * @property-read Revision $revision
@@ -43,4 +45,60 @@ class Proposal extends BaseModel
     {
         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(),
+        ]);
+    }
 }

app/Tables/Changeset.php

@@ -3,15 +3,44 @@
 
 namespace App\Tables;
 
+use App\Models\Revision;
+use App\Models\Table;
+use Illuminate\Queue\SerializesModels;
+use ReflectionClass;
+
 /**
  * Object representing a set of table modifications
  */
 class Changeset
 {
+    use SerializesModels;
+
+    const object_excluded_properties = [
+        'revision',
+        'table',
+        'note',
+    ];
+
+    /**
+     * @var Revision - base revision this changeset belongs to
+     */
+    public $revision;
+
+    /**
+     * @var Table - table this changeset belongs to
+     */
+    public $table;
+
+    /**
+     * @var string - user's note attached to this changeset (future proposal)
+     */
+    public $note;
+
     /**
-     * Rows whose content changed
+     * Rows whose content changed, identified by _id.
+     * Only changed values are to be filled. Columns are identified by GCIDs
      *
-     * @var array|null - [GRID -> values, ...]
+     * @var array|null - [[_id:…, …], …]
      */
     public $rowUpdates;
 
@@ -19,7 +48,7 @@ class Changeset
      * New rows in the full Row::data format, including GRIDs.
      * Values are identified by GCIDs from previously defined, or new columns.
      *
-     * @var array|null - [[_id:..., ...], [..., ...], ...]
+     * @var array|null - [[_id:…, …], …]
      */
     public $newRows;
 
@@ -41,7 +70,7 @@ class Changeset
     /**
      * New columns in the full format, including GCIDs
      *
-     * @var array|null - [[id:..., ...], [..., ...], ...]
+     * @var array|null - [[id:…, …], …]
      */
     public $newColumns;
 
@@ -66,4 +95,65 @@ class Changeset
      * @var int[]|null - GCIDs
      */
     public $removedColumns;
+
+    private function walkProps()
+    {
+        $properties = (new ReflectionClass($this))->getProperties();
+
+        foreach ($properties as $property) {
+            if (in_array($property->name, self::object_excluded_properties)) {
+                continue;
+            }
+
+            yield $property->name;
+        }
+    }
+
+    /**
+     * Reconstruct from a object, such as one found in Proposal.
+     * Note that the fromProposal() method should be used when the
+     * proposal is available, as it populates additional fields.
+     *
+     * @param \stdClass $changes
+     * @return Changeset
+     */
+    public static function fromObject($changes)
+    {
+        $changeset = new Changeset();
+
+        foreach ($changeset->walkProps() as $prop) {
+            if (isset($changes->$prop)) {
+                $changeset->$prop = $changes->$prop;
+            }
+        }
+
+        return $changeset;
+    }
+
+    /**
+     * Serialize to an object format that may be stored in a Proposal.
+     *
+     * @return \stdClass
+     */
+    public function toObject()
+    {
+        $object = new \stdClass();
+
+        foreach ($this->walkProps() as $prop) {
+            $object->$prop = array_values($this->$prop);
+        }
+
+        return $object;
+    }
+
+    public function hasAnyChanges()
+    {
+        foreach ($this->walkProps() as $prop) {
+            if (!empty($this->$prop)) {
+                return true;
+            }
+        }
+
+        return false;
+    }
 }