<?php

declare(strict_types=1);

namespace App\Domain\Chat;

use DateTimeImmutable;
use DateTimeInterface;

final class Message
{
    /**
     * @param array<ToolCall>|null $toolCalls
     */
    public function __construct(
        private readonly string $role,
        private readonly ?string $content,
        private readonly ?array $toolCalls = null,
        private readonly ?ToolResult $toolResult = null,
        private readonly DateTimeInterface $createdAt = new DateTimeImmutable(),
    ) {
    }

    public function getRole(): string
    {
        return $this->role;
    }

    public function getContent(): ?string
    {
        return $this->content;
    }

    public function getTwig(): ?string
    {
        $content = $this->getContent() ?? '```twig\n{}\n```';
        $matches = [];
        if (preg_match('/```twig\s*([\s\S]*?)\s*```/m', $content, $matches) > 0) {
            return $matches[1];
        }

        return null;
    }

    /**
     * @return array<string, mixed>|null
     */
    public function getJson(): ?array
    {
        $content = $this->getContent() ?? '```json\n{}\n```';
        $matches = [];
        if (preg_match('/```json\s*([\s\S]*?)\s*```/m', $content, $matches) > 0) {
            $decoded = json_decode($matches[1], true);
            return is_array($decoded) ? $decoded : null;
        }
        
        return null;
    }

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

    /**
     * @return array<ToolCall>
     */
    public function getToolCalls(): array
    {
        return $this->toolCalls ?? [];
    }

    public function getToolResult(): ?ToolResult
    {
        if (isset($this->toolResult)) {
            return $this->toolResult;
        }

        return null;
    }

    /**
     * @return array<string, mixed>
     */
    public function toArray(): array
    {
        $result = [
            'role' => $this->role,
        ];

        if ($this->content !== null) {
            $result['content'] = $this->content;
        }

        if ($this->toolResult !== null) {
            $result['tool_call_id'] = $this->toolResult->getToolCallId();
        }

        if ($this->toolCalls !== null && $this->toolCalls !== []) {
            $result['tool_calls'] = array_map(
                fn (ToolCall $toolCall) => [
                    'id' => $toolCall->getId(),
                    'type' => $toolCall->getType(),
                    'function' => [
                        'name' => $toolCall->getName(),
                        'arguments' => json_encode($toolCall->getArguments()),
                    ],
                ],
                $this->toolCalls
            );
        }

        return $result;
    }

    public static function fromUser(string $content): self
    {
        return new self(role: 'user', content: $content);
    }

    public static function fromSystem(string $content): self
    {
        return new self(role: 'system', content: $content);
    }

    /**
     * @param array<ToolCall>|null $toolCalls
     */
    public static function fromAssistant(?string $content = null, ?array $toolCalls = null): self
    {
        return new self(role: 'assistant', content: $content, toolCalls: $toolCalls);
    }

    public static function fromToolResult(string $content, string $toolCallId, string $toolName): self
    {
        return new self(role: 'tool', content: $content, toolResult: new ToolResult($toolCallId, $toolName));
    }
}