<?php

namespace Tests\Feature;

use App\Models\Bucket;
use App\Models\Scenario;
use Illuminate\Foundation\Testing\RefreshDatabase;
use Tests\TestCase;

class ProjectionPreviewTest extends TestCase
{
    use RefreshDatabase;

    private Scenario $scenario;

    protected function setUp(): void
    {
        parent::setUp();
        $this->scenario = Scenario::factory()->create();
    }

    public function test_preview_returns_correct_allocations(): void
    {
        Bucket::factory()->need()->fixedLimit(50000)->create([
            'scenario_id' => $this->scenario->id,
            'name' => 'Rent',
            'priority' => 1,
            'starting_amount' => 0,
        ]);

        Bucket::factory()->want()->fixedLimit(30000)->create([
            'scenario_id' => $this->scenario->id,
            'name' => 'Fun',
            'priority' => 2,
            'starting_amount' => 0,
        ]);

        // Send 70000 cents = $700
        $response = $this->postJson(
            "/scenarios/{$this->scenario->uuid}/projections/preview",
            ['amount' => 70000]
        );

        $response->assertOk();
        $response->assertJsonCount(2, 'allocations');
        $response->assertJsonPath('allocations.0.bucket_name', 'Rent');
        $response->assertJsonPath('allocations.0.allocated_amount', 50000);
        $response->assertJsonPath('allocations.1.bucket_name', 'Fun');
        $response->assertJsonPath('allocations.1.allocated_amount', 20000);
        $response->assertJsonPath('total_allocated', 70000);
        $response->assertJsonPath('unallocated', 0);
    }

    public function test_preview_returns_remaining_capacity(): void
    {
        Bucket::factory()->need()->fixedLimit(50000)->create([
            'scenario_id' => $this->scenario->id,
            'name' => 'Savings',
            'priority' => 1,
            'starting_amount' => 0,
        ]);

        // Send 30000 cents = $300
        $response = $this->postJson(
            "/scenarios/{$this->scenario->uuid}/projections/preview",
            ['amount' => 30000]
        );

        $response->assertOk();
        $response->assertJsonPath('allocations.0.allocated_amount', 30000);
        $response->assertJsonPath('allocations.0.remaining_capacity', 20000);
    }

    public function test_preview_returns_uuids_not_integer_ids(): void
    {
        $bucket = Bucket::factory()->need()->fixedLimit(50000)->create([
            'scenario_id' => $this->scenario->id,
            'priority' => 1,
            'starting_amount' => 0,
        ]);

        $response = $this->postJson(
            "/scenarios/{$this->scenario->uuid}/projections/preview",
            ['amount' => 10000]
        );

        $response->assertOk();
        $response->assertJsonPath('allocations.0.bucket_id', $bucket->uuid);
    }

    public function test_preview_includes_bucket_type(): void
    {
        Bucket::factory()->need()->fixedLimit(50000)->create([
            'scenario_id' => $this->scenario->id,
            'priority' => 1,
            'starting_amount' => 0,
        ]);

        $response = $this->postJson(
            "/scenarios/{$this->scenario->uuid}/projections/preview",
            ['amount' => 10000]
        );

        $response->assertOk();
        $response->assertJsonPath('allocations.0.bucket_type', 'need');
    }

    public function test_preview_rejects_missing_amount(): void
    {
        $response = $this->postJson(
            "/scenarios/{$this->scenario->uuid}/projections/preview",
            []
        );

        $response->assertUnprocessable();
        $response->assertJsonValidationErrors('amount');
    }

    public function test_preview_rejects_zero_amount(): void
    {
        $response = $this->postJson(
            "/scenarios/{$this->scenario->uuid}/projections/preview",
            ['amount' => 0]
        );

        $response->assertUnprocessable();
        $response->assertJsonValidationErrors('amount');
    }

    public function test_preview_rejects_negative_amount(): void
    {
        $response = $this->postJson(
            "/scenarios/{$this->scenario->uuid}/projections/preview",
            ['amount' => -50]
        );

        $response->assertUnprocessable();
        $response->assertJsonValidationErrors('amount');
    }

    public function test_preview_with_no_buckets_returns_empty_allocations(): void
    {
        $response = $this->postJson(
            "/scenarios/{$this->scenario->uuid}/projections/preview",
            ['amount' => 100000]
        );

        $response->assertOk();
        $response->assertJsonPath('allocations', []);
        $response->assertJsonPath('total_allocated', 0);
        $response->assertJsonPath('unallocated', 100000);
    }

    public function test_preview_respects_priority_ordering(): void
    {
        Bucket::factory()->want()->fixedLimit(20000)->create([
            'scenario_id' => $this->scenario->id,
            'name' => 'Low Priority',
            'priority' => 3,
            'starting_amount' => 0,
        ]);

        Bucket::factory()->need()->fixedLimit(30000)->create([
            'scenario_id' => $this->scenario->id,
            'name' => 'High Priority',
            'priority' => 1,
            'starting_amount' => 0,
        ]);

        $response = $this->postJson(
            "/scenarios/{$this->scenario->uuid}/projections/preview",
            ['amount' => 40000]
        );

        $response->assertOk();
        $response->assertJsonPath('allocations.0.bucket_name', 'High Priority');
        $response->assertJsonPath('allocations.0.allocated_amount', 30000);
        $response->assertJsonPath('allocations.1.bucket_name', 'Low Priority');
        $response->assertJsonPath('allocations.1.allocated_amount', 10000);
    }

    public function test_preview_with_overflow_bucket_captures_remainder(): void
    {
        Bucket::factory()->need()->fixedLimit(20000)->create([
            'scenario_id' => $this->scenario->id,
            'name' => 'Rent',
            'priority' => 1,
            'starting_amount' => 0,
        ]);

        Bucket::factory()->overflow()->create([
            'scenario_id' => $this->scenario->id,
            'name' => 'Overflow',
            'priority' => 2,
            'starting_amount' => 0,
        ]);

        $response = $this->postJson(
            "/scenarios/{$this->scenario->uuid}/projections/preview",
            ['amount' => 50000]
        );

        $response->assertOk();
        $response->assertJsonPath('allocations.0.bucket_name', 'Rent');
        $response->assertJsonPath('allocations.0.allocated_amount', 20000);
        $response->assertJsonPath('allocations.1.bucket_name', 'Overflow');
        $response->assertJsonPath('allocations.1.allocated_amount', 30000);
        $response->assertJsonPath('allocations.1.remaining_capacity', null);
        $response->assertJsonPath('total_allocated', 50000);
        $response->assertJsonPath('unallocated', 0);
    }
}