<?php

namespace Modules\FinancialManagement\Models;

use App\Traits\HasPublicIdentifier;
use Illuminate\Database\Eloquent\Model;
use Illuminate\Database\Eloquent\Relations\BelongsTo;
use Illuminate\Database\Eloquent\Relations\HasMany;
use Modules\ApprovalWorkflow\Traits\HasApprovable;
use Modules\FinancialManagement\Enums\InvoiceStatus;
use Modules\ProjectManagement\Models\Project;
use Modules\ApprovalWorkflow\Models\ApprovalChain;
use Modules\FinancialManagement\Services\ProgressBillingService;

class FinancialInvoice extends Model
{
    use HasApprovable, HasPublicIdentifier;

    protected $table = 'financial_invoices';

    protected $fillable = [
        'project_id', 'invoice_number', 'status',
        'subtotal', 'retention_amount', 'total_amount', 'paid_amount',
        'retention_rate', 'billed_percentage',
        'penalty_rate', 'penalty_amount', 'penalty_reason',
        'penalty_applied_by', 'penalty_applied_at',
        'invoice_date', 'due_date', 'notes',
        'payment_proof_path', 'payment_proof_name', 'payment_proof_notes',
        'payment_proof_submitted_by', 'payment_proof_submitted_at',
        'submitted_at', 'approved_at', 'sent_at', 'paid_at',
    ];

    protected function casts(): array
    {
        return [
            'status' => InvoiceStatus::class,
            'subtotal' => 'decimal:2',
            'retention_amount' => 'decimal:2',
            'total_amount' => 'decimal:2',
            'paid_amount' => 'decimal:2',
            'retention_rate' => 'decimal:2',
            'billed_percentage' => 'decimal:2',
            'penalty_rate' => 'decimal:2',
            'penalty_amount' => 'decimal:2',
            'penalty_applied_at' => 'datetime',
            'invoice_date' => 'date',
            'due_date' => 'date',
            'payment_proof_submitted_at' => 'datetime',
            'submitted_at' => 'datetime',
            'approved_at' => 'datetime',
            'sent_at' => 'datetime',
            'paid_at' => 'datetime',
        ];
    }

    protected static function booted(): void
    {
        static::saved(function (FinancialInvoice $invoice) {
            if ($invoice->status === InvoiceStatus::Paid && (float) $invoice->retention_amount > 0) {
                $totalDue = (float) $invoice->retention_amount + (float) ($invoice->penalty_amount ?? 0);
                $credit = RetentionEntry::where([
                    'project_id' => $invoice->project_id,
                    'invoice_id' => $invoice->id,
                    'type' => 'credit',
                ])->first();

                $desc = (float) ($invoice->penalty_amount ?? 0) > 0
                    ? "Retention & Late Penalty Remittance Settled & Confirmed for Invoice #{$invoice->invoice_number}"
                    : "10% Retention Remittance Settled & Confirmed for Invoice #{$invoice->invoice_number}";

                if (!$credit) {
                    RetentionEntry::create([
                        'project_id' => $invoice->project_id,
                        'invoice_id' => $invoice->id,
                        'type' => 'credit',
                        'status' => 'paid',
                        'amount' => $totalDue,
                        'description' => $desc,
                    ]);
                } elseif ((float) $credit->amount !== $totalDue) {
                    $credit->update([
                        'amount' => $totalDue,
                        'status' => 'paid',
                        'description' => $desc,
                    ]);
                }
            }
        });
    }

    public function penaltyAppliedBy(): BelongsTo
    {
        return $this->belongsTo(\App\Models\User::class, 'penalty_applied_by');
    }

    public function paymentProofSubmittedBy(): BelongsTo
    {
        return $this->belongsTo(\App\Models\User::class, 'payment_proof_submitted_by');
    }

    public function project(): BelongsTo
    {
        return $this->belongsTo(Project::class);
    }

    public function lineItems(): HasMany
    {
        return $this->hasMany(InvoiceLineItem::class, 'invoice_id')->orderBy('sort_order');
    }

    public function retentionEntries(): HasMany
    {
        return $this->hasMany(RetentionEntry::class, 'invoice_id');
    }

    public function transitionTo(InvoiceStatus $newStatus): void
    {
        $allowed = $this->status->allowedTransitions();
        if (!in_array($newStatus, $allowed)) {
            throw new \InvalidArgumentException(
                "Cannot transition invoice from {$this->status->label()} to {$newStatus->label()}"
            );
        }

        $updates = ['status' => $newStatus];
        match ($newStatus) {
            InvoiceStatus::Submitted => $updates['submitted_at'] = now(),
            InvoiceStatus::Approved => $updates['approved_at'] = now(),
            InvoiceStatus::Sent => $updates['sent_at'] = now(),
            InvoiceStatus::Paid => $updates['paid_at'] = now(),
            default => null,
        };

        $this->update($updates);
    }

    public function getBalanceDueAttribute(): float
    {
        return (float) $this->total_amount - (float) $this->paid_amount;
    }

    public function getIsOverdueAttribute(): bool
    {
        return $this->due_date
            && $this->due_date->isPast()
            && !in_array($this->status, [InvoiceStatus::Paid]);
    }

    public function onApprovalCompleted(ApprovalChain $chain): void
    {
        if ($chain->status->value === 'approved') {
            $this->update([
                'status' => InvoiceStatus::Approved,
                'approved_at' => now(),
            ]);

            app(ProgressBillingService::class)->holdRetention($this);
        } elseif ($chain->status->value === 'rejected') {
            $this->update(['status' => InvoiceStatus::Rejected]);
        }
    }
}