<?php

declare(strict_types=1);

namespace Domain\Entity;

// @responsibility: Chat-Session-Entitaet mit Konfigurations-Management

class ChatSession
{
    private ?int $id = null;
    private string $uuid;
    private ?string $sessionToken = null;
    private ?int $userId = null;
    private ?int $personaId = null;
    private ?string $title = null;
    private string $model = 'claude-opus-4-5-20251101';
    /** @var array<string> */
    private array $collections = ['documents'];
    private int $contextLimit = 5;
    private float $temperature = 0.7;
    private int $maxTokens = 4096;
    private ?int $authorProfileId = null;
    private ?int $systemPromptId = null;
    private \DateTimeImmutable $createdAt;
    private \DateTimeImmutable $updatedAt;
    private \DateTimeImmutable $lastActivity;

    public function __construct()
    {
        $this->uuid = $this->generateUuid();
        $this->createdAt = new \DateTimeImmutable();
        $this->updatedAt = new \DateTimeImmutable();
        $this->lastActivity = new \DateTimeImmutable();
    }

    private function generateUuid(): string
    {
        $data = random_bytes(16);
        $data[6] = chr(ord($data[6]) & 0x0f | 0x40);
        $data[8] = chr(ord($data[8]) & 0x3f | 0x80);

        return vsprintf('%s%s-%s-%s-%s-%s%s%s', str_split(bin2hex($data), 4));
    }

    // Getters
    public function getId(): ?int
    {
        return $this->id;
    }

    public function getUuid(): string
    {
        return $this->uuid;
    }

    public function getSessionToken(): ?string
    {
        return $this->sessionToken;
    }

    public function getUserId(): ?int
    {
        return $this->userId;
    }

    public function getPersonaId(): ?int
    {
        return $this->personaId;
    }

    public function getTitle(): ?string
    {
        return $this->title;
    }

    public function getModel(): string
    {
        return $this->model;
    }

    /**
     * @return array<string>
     */
    public function getCollections(): array
    {
        return $this->collections;
    }

    public function getContextLimit(): int
    {
        return $this->contextLimit;
    }

    public function getTemperature(): float
    {
        return $this->temperature;
    }

    public function getMaxTokens(): int
    {
        return $this->maxTokens;
    }

    public function getAuthorProfileId(): ?int
    {
        return $this->authorProfileId;
    }

    public function getSystemPromptId(): ?int
    {
        return $this->systemPromptId;
    }

    public function getCreatedAt(): \DateTimeImmutable
    {
        return $this->createdAt;
    }

    public function getUpdatedAt(): \DateTimeImmutable
    {
        return $this->updatedAt;
    }

    public function getLastActivity(): \DateTimeImmutable
    {
        return $this->lastActivity;
    }

    // Setters with fluent interface
    public function setId(int $id): self
    {
        $this->id = $id;

        return $this;
    }

    public function setUuid(string $uuid): self
    {
        $this->uuid = $uuid;

        return $this;
    }

    public function setSessionToken(?string $sessionToken): self
    {
        $this->sessionToken = $sessionToken;

        return $this;
    }

    public function setUserId(?int $userId): self
    {
        $this->userId = $userId;

        return $this;
    }

    public function setPersonaId(?int $personaId): self
    {
        $this->personaId = $personaId;

        return $this;
    }

    public function setTitle(string $title): self
    {
        $this->title = $title;
        $this->touch();

        return $this;
    }

    public function setModel(string $model): self
    {
        $this->model = $model;
        $this->touch();

        return $this;
    }

    /**
     * @param array<string> $collections
     */
    public function setCollections(array $collections): self
    {
        $this->collections = $collections;
        $this->touch();

        return $this;
    }

    public function setContextLimit(int $contextLimit): self
    {
        $this->contextLimit = $contextLimit;
        $this->touch();

        return $this;
    }

    public function setTemperature(float $temperature): self
    {
        $this->temperature = $temperature;
        $this->touch();

        return $this;
    }

    public function setMaxTokens(int $maxTokens): self
    {
        $this->maxTokens = $maxTokens;
        $this->touch();

        return $this;
    }

    public function setAuthorProfileId(?int $authorProfileId): self
    {
        $this->authorProfileId = $authorProfileId;
        $this->touch();

        return $this;
    }

    public function setSystemPromptId(?int $systemPromptId): self
    {
        $this->systemPromptId = $systemPromptId;
        $this->touch();

        return $this;
    }

    public function setCreatedAt(\DateTimeImmutable $createdAt): self
    {
        $this->createdAt = $createdAt;

        return $this;
    }

    public function setUpdatedAt(\DateTimeImmutable $updatedAt): self
    {
        $this->updatedAt = $updatedAt;

        return $this;
    }

    public function setLastActivity(\DateTimeImmutable $lastActivity): self
    {
        $this->lastActivity = $lastActivity;

        return $this;
    }

    /**
     * Update timestamps on modification.
     */
    private function touch(): void
    {
        $this->updatedAt = new \DateTimeImmutable();
        $this->lastActivity = new \DateTimeImmutable();
    }

    /**
     * Factory method for creating a new session.
     *
     * @param array<string> $collections
     */
    public static function create(
        string $uuid,
        string $model = 'claude-opus-4-5-20251101',
        array $collections = ['documents'],
        int $contextLimit = 5
    ): self {
        $session = new self();
        $session->uuid = $uuid;
        $session->model = $model;
        $session->collections = $collections;
        $session->contextLimit = $contextLimit;

        return $session;
    }

    /**
     * Create a copy with new ID (for post-save).
     */
    public function withId(int $id): self
    {
        $clone = clone $this;
        $clone->id = $id;

        return $clone;
    }

    /**
     * Update settings in one call.
     */
    public function updateSettings(
        string $model,
        array $collections,
        int $contextLimit,
        ?int $authorProfileId,
        float $temperature,
        int $maxTokens
    ): self {
        $this->model = $model;
        $this->collections = $collections;
        $this->contextLimit = $contextLimit;
        $this->authorProfileId = $authorProfileId;
        $this->temperature = $temperature;
        $this->maxTokens = $maxTokens;
        $this->touch();

        return $this;
    }

    /**
     * Convert to array for persistence.
     *
     * @return array<string, mixed>
     */
    public function toArray(): array
    {
        return [
            'id' => $this->id,
            'uuid' => $this->uuid,
            'session_token' => $this->sessionToken,
            'user_id' => $this->userId,
            'persona_id' => $this->personaId,
            'title' => $this->title,
            'model' => $this->model,
            'collections' => json_encode($this->collections),
            'context_limit' => $this->contextLimit,
            'temperature' => $this->temperature,
            'max_tokens' => $this->maxTokens,
            'author_profile_id' => $this->authorProfileId,
            'system_prompt_id' => $this->systemPromptId,
            'created_at' => $this->createdAt->format('Y-m-d H:i:s'),
            'updated_at' => $this->updatedAt->format('Y-m-d H:i:s'),
            'last_activity' => $this->lastActivity->format('Y-m-d H:i:s'),
        ];
    }

    /**
     * Create from database row.
     *
     * @param array<string, mixed> $data
     */
    public static function fromArray(array $data): self
    {
        $session = new self();

        if (isset($data['id'])) {
            $session->setId((int) $data['id']);
        }
        if (isset($data['uuid'])) {
            $session->setUuid($data['uuid']);
        }
        if (isset($data['session_token'])) {
            $session->setSessionToken($data['session_token']);
        }
        if (isset($data['user_id'])) {
            $session->setUserId((int) $data['user_id']);
        }
        if (isset($data['persona_id'])) {
            $session->setPersonaId((int) $data['persona_id']);
        }
        if (isset($data['title'])) {
            $session->title = $data['title'];
        }
        if (isset($data['model'])) {
            $session->model = $data['model'];
        }
        if (isset($data['collections'])) {
            $collections = is_string($data['collections'])
                ? json_decode($data['collections'], true)
                : $data['collections'];
            $session->collections = is_array($collections) ? $collections : ['documents'];
        }
        if (isset($data['context_limit'])) {
            $session->contextLimit = (int) $data['context_limit'];
        }
        if (isset($data['temperature'])) {
            $session->temperature = (float) $data['temperature'];
        }
        if (isset($data['max_tokens'])) {
            $session->maxTokens = (int) $data['max_tokens'];
        }
        if (isset($data['author_profile_id'])) {
            $session->authorProfileId = (int) $data['author_profile_id'];
        }
        if (isset($data['system_prompt_id'])) {
            $session->systemPromptId = (int) $data['system_prompt_id'];
        }
        if (isset($data['created_at'])) {
            $session->createdAt = new \DateTimeImmutable($data['created_at']);
        }
        if (isset($data['updated_at'])) {
            $session->updatedAt = new \DateTimeImmutable($data['updated_at']);
        }
        if (isset($data['last_activity'])) {
            $session->lastActivity = new \DateTimeImmutable($data['last_activity']);
        }

        return $session;
    }
}