<?php

declare(strict_types=1);

namespace App\Support\Baselines\CompareSemantics;

use App\Support\OperationRunOutcome;

final class BaselineCompareRunSummaryClassifier
{
    /**
     * @param  list<CompareSubjectOutcome|array<string, mixed>>  $subjectOutcomes
     * @param  list<string>  $uncoveredTypes
     * @return array{
     *   run_outcome: string,
     *   operation_outcome: string,
     *   counts: array<string, array<string, int>>
     * }
     */
    public function summarize(
        array $subjectOutcomes,
        int $driftFindingsCount,
        bool $warningsRecorded,
        bool $resumeTokenPresent = false,
        array $uncoveredTypes = [],
    ): array {
        $counts = [
            'by_reason' => [],
            'by_category' => [],
            'by_actionability' => [],
            'by_readiness_impact' => [],
        ];

        $verifiedSubjectCount = 0;
        $blockingSubjectCount = 0;
        $failedSubjectCount = 0;

        foreach ($subjectOutcomes as $outcome) {
            $outcome = $outcome instanceof CompareSubjectOutcome ? $outcome->toArray() : $outcome;

            if (! is_array($outcome)) {
                continue;
            }

            $reason = $this->nonEmptyString($outcome['reason'] ?? null);
            $category = $this->nonEmptyString($outcome['category'] ?? null);
            $actionability = $this->nonEmptyString($outcome['actionability'] ?? null);
            $readinessImpact = $this->nonEmptyString($outcome['readiness_impact'] ?? null);

            $this->increment($counts['by_reason'], $reason);
            $this->increment($counts['by_category'], $category);
            $this->increment($counts['by_actionability'], $actionability);
            $this->increment($counts['by_readiness_impact'], $readinessImpact);

            if (in_array($category, [CompareResultCategory::Verified->value, CompareResultCategory::DriftDetected->value], true)) {
                $verifiedSubjectCount++;
            }

            if (in_array($readinessImpact, [CompareResultReadinessImpact::CustomerBlocker->value, CompareResultReadinessImpact::InternalBlocker->value], true)) {
                $blockingSubjectCount++;
            }

            if ($category === CompareResultCategory::Failed->value) {
                $failedSubjectCount++;
            }
        }

        foreach ($counts as &$bucket) {
            ksort($bucket);
        }
        unset($bucket);

        $hasWarnings = $warningsRecorded || $resumeTokenPresent || $uncoveredTypes !== [];
        $runOutcome = $this->runOutcome(
            driftFindingsCount: $driftFindingsCount,
            verifiedSubjectCount: $verifiedSubjectCount,
            blockingSubjectCount: $blockingSubjectCount,
            failedSubjectCount: $failedSubjectCount,
            hasWarnings: $hasWarnings,
        );

        return [
            'run_outcome' => $runOutcome->value,
            'operation_outcome' => in_array($runOutcome, [CompareRunOutcome::Completed, CompareRunOutcome::CompletedWithDrift], true)
                ? OperationRunOutcome::Succeeded->value
                : OperationRunOutcome::PartiallySucceeded->value,
            'counts' => $counts,
        ];
    }

    private function runOutcome(
        int $driftFindingsCount,
        int $verifiedSubjectCount,
        int $blockingSubjectCount,
        int $failedSubjectCount,
        bool $hasWarnings,
    ): CompareRunOutcome {
        if ($failedSubjectCount > 0 && $verifiedSubjectCount === 0 && $driftFindingsCount === 0) {
            return CompareRunOutcome::Failed;
        }

        if ($blockingSubjectCount > 0 && $verifiedSubjectCount === 0 && $driftFindingsCount === 0) {
            return CompareRunOutcome::Blocked;
        }

        if ($hasWarnings || $blockingSubjectCount > 0 || $failedSubjectCount > 0) {
            return CompareRunOutcome::Partial;
        }

        return $driftFindingsCount > 0
            ? CompareRunOutcome::CompletedWithDrift
            : CompareRunOutcome::Completed;
    }

    /**
     * @param  array<string, int>  $counts
     */
    private function increment(array &$counts, ?string $key): void
    {
        if ($key === null) {
            return;
        }

        $counts[$key] = ($counts[$key] ?? 0) + 1;
    }

    private function nonEmptyString(mixed $value): ?string
    {
        if (! is_string($value) || trim($value) === '') {
            return null;
        }

        return trim($value);
    }
}