<?php
declare(strict_types = 1);

namespace Gettext;

/**
 * Class to manage an individual translation.
 */
class Translation
{
    protected $id;
    protected $context;
    protected $original;
    protected $plural;
    protected $translation;
    protected $pluralTranslations = [];
    protected $disabled = false;
    protected $references;
    protected $flags;
    protected $comments;
    protected $extractedComments;
    protected $previousContext;
    protected $previousOriginal;
    protected $previousPlural;

    public static function create(?string $context, string $original): Translation
    {
        $id = static::generateId($context, $original);

        $translation = new static($id);
        $translation->context = $context;
        $translation->original = $original;

        return $translation;
    }

    protected static function generateId(?string $context, string $original): string
    {
        return "{$context}\004{$original}";
    }

    protected function __construct(string $id)
    {
        $this->id = $id;

        $this->references = new References();
        $this->flags = new Flags();
        $this->comments = new Comments();
        $this->extractedComments = new Comments();
    }

    public function __clone()
    {
        $this->references = clone $this->references;
        $this->flags = clone $this->flags;
        $this->comments = clone $this->comments;
        $this->extractedComments = clone $this->extractedComments;
    }

    public function toArray(): array
    {
        return [
            'id' => $this->id,
            'context' => $this->context,
            'original' => $this->original,
            'translation' => $this->translation,
            'plural' => $this->plural,
            'pluralTranslations' => $this->pluralTranslations,
            'disabled' => $this->disabled,
            'previousContext' => $this->previousContext,
            'previousOriginal' => $this->previousOriginal,
            'previousPlural' => $this->previousPlural,
            'references' => $this->getReferences()->toArray(),
            'flags' => $this->getFlags()->toArray(),
            'comments' => $this->getComments()->toArray(),
            'extractedComments' => $this->getExtractedComments()->toArray(),
        ];
    }

    public function getId(): string
    {
        return $this->id;
    }

    public function getContext(): ?string
    {
        return $this->context;
    }

    public function withContext(?string $context): Translation
    {
        $clone = clone $this;
        $clone->context = $context;
        $clone->id = static::generateId($clone->getContext(), $clone->getOriginal());

        return $clone;
    }

    public function getOriginal(): string
    {
        return $this->original;
    }

    public function withOriginal(string $original): Translation
    {
        $clone = clone $this;
        $clone->original = $original;
        $clone->id = static::generateId($clone->getContext(), $clone->getOriginal());

        return $clone;
    }

    public function setPlural(string $plural): self
    {
        $this->plural = $plural;

        return $this;
    }

    public function getPlural(): ?string
    {
        return $this->plural;
    }

    public function setPreviousOriginal(?string $previousOriginal): self
    {
        $this->previousOriginal = $previousOriginal;

        return $this;
    }

    public function getPreviousOriginal(): ?string
    {
        return $this->previousOriginal;
    }

    public function setPreviousContext(?string $previousContext): self
    {
        $this->previousContext = $previousContext;

        return $this;
    }

    public function getPreviousContext(): ?string
    {
        return $this->previousContext;
    }

    public function setPreviousPlural(?string $previousPlural): self
    {
        $this->previousPlural = $previousPlural;

        return $this;
    }

    public function getPreviousPlural(): ?string
    {
        return $this->previousPlural;
    }

    public function disable(bool $disabled = true): self
    {
        $this->disabled = $disabled;

        return $this;
    }

    public function isDisabled(): bool
    {
        return $this->disabled;
    }

    public function translate(string $translation): self
    {
        $this->translation = $translation;

        return $this;
    }

    public function getTranslation(): ?string
    {
        return $this->translation;
    }

    public function isTranslated(): bool
    {
        return isset($this->translation) && $this->translation !== '';
    }

    public function translatePlural(string ...$translations): self
    {
        $this->pluralTranslations = $translations;

        return $this;
    }

    public function getPluralTranslations(?int $size = null): array
    {
        if ($size === null) {
            return $this->pluralTranslations;
        }

        $length = count($this->pluralTranslations);

        if ($size > $length) {
            return $this->pluralTranslations + array_fill(0, $size, '');
        }

        return array_slice($this->pluralTranslations, 0, $size);
    }

    public function getReferences(): References
    {
        return $this->references;
    }

    public function getFlags(): Flags
    {
        return $this->flags;
    }

    public function getComments(): Comments
    {
        return $this->comments;
    }

    public function getExtractedComments(): Comments
    {
        return $this->extractedComments;
    }

    public function mergeWith(Translation $translation, int $strategy = 0): Translation
    {
        $merged = clone $this;

        if ($strategy & Merge::COMMENTS_THEIRS) {
            $merged->comments = clone $translation->comments;
        } elseif (!($strategy & Merge::COMMENTS_OURS)) {
            $merged->comments = $merged->comments->mergeWith($translation->comments);
        }

        if ($strategy & Merge::EXTRACTED_COMMENTS_THEIRS) {
            $merged->extractedComments = clone $translation->extractedComments;
        } elseif (!($strategy & Merge::EXTRACTED_COMMENTS_OURS)) {
            $merged->extractedComments = $merged->extractedComments->mergeWith($translation->extractedComments);
        }

        if ($strategy & Merge::REFERENCES_THEIRS) {
            $merged->references = clone $translation->references;
        } elseif (!($strategy & Merge::REFERENCES_OURS)) {
            $merged->references = $merged->references->mergeWith($translation->references);
        }

        if ($strategy & Merge::FLAGS_THEIRS) {
            $merged->flags = clone $translation->flags;
        } elseif (!($strategy & Merge::FLAGS_OURS)) {
            $merged->flags = $merged->flags->mergeWith($translation->flags);
        }

        $override = (bool) ($strategy & Merge::TRANSLATIONS_OVERRIDE);

        if (!$merged->translation || ($translation->translation && $override)) {
            $merged->translation = $translation->translation;
        }

        if (!$merged->plural || ($translation->plural && $override)) {
            $merged->plural = $translation->plural;
        }

        if (!$merged->previousContext || ($translation->previousContext && $override)) {
            $merged->previousContext = $translation->previousContext;
        }

        if (!$merged->previousOriginal || ($translation->previousOriginal && $override)) {
            $merged->previousOriginal = $translation->previousOriginal;
        }

        if (!$merged->previousPlural || ($translation->previousPlural && $override)) {
            $merged->previousPlural = $translation->previousPlural;
        }

        if (empty($merged->pluralTranslations) || (!empty($translation->pluralTranslations) && $override)) {
            $merged->pluralTranslations = $translation->pluralTranslations;
        }

        $merged->disable($translation->isDisabled());

        return $merged;
    }
}