<?php

declare(strict_types=1);

namespace EKSRelay\Clients;

use EKSRelay\Core\Env;
use EKSRelay\Core\HttpClient;
use EKSRelay\Core\HttpException;
use EKSRelay\Core\Logger;

final class ChatwootClient
{
    private string $baseUrl;
    private string $token;
    private int $accountId;

    public function __construct()
    {
        $this->baseUrl   = rtrim(Env::get('CHATWOOT_BASE_URL'), '/');
        $this->token     = Env::get('CHATWOOT_API_TOKEN');
        $this->accountId = Env::getInt('CHATWOOT_ACCOUNT_ID', 1);
    }

    // ---------------------------------------------------------------
    // API helpers
    // ---------------------------------------------------------------

    private function apiUrl(string $path): string
    {
        // Chatwoot v2/v3 API: /api/v1/accounts/{account_id}/...
        return "{$this->baseUrl}/api/v1/accounts/{$this->accountId}{$path}";
    }

    private function authHeaders(): array
    {
        return ["api_access_token: {$this->token}"];
    }

    /**
     * @return array Decoded JSON response
     */
    private function api(string $method, string $path, ?array $body = null): array
    {
        $url = $this->apiUrl($path);
        $res = HttpClient::request($method, $url, $this->authHeaders(), $body);

        if ($res['status'] >= 400) {
            Logger::warn("Chatwoot API error", [
                'method' => $method,
                'path'   => $path,
                'status' => $res['status'],
                'body'   => mb_substr($res['body'], 0, 500),
            ]);
            throw new HttpException(502, 'CHATWOOT_API_ERROR', "Chatwoot returned HTTP {$res['status']}");
        }

        return $res['json'] ?? [];
    }

    // ---------------------------------------------------------------
    // Public methods
    // ---------------------------------------------------------------

    /**
     * Get full conversation details (labels, custom_attributes, etc.).
     */
    public function getConversation(int $conversationId): array
    {
        return $this->api('GET', "/conversations/{$conversationId}");
    }

    /**
     * Add a label to a conversation.
     * Chatwoot API: POST /conversations/{id}/labels  (Chatwoot >= v2.14)
     * The endpoint expects { "labels": ["label1","label2"] } and REPLACES all labels,
     * so we first fetch existing labels and merge.
     *
     * NOTE: Chatwoot label API behaviour may vary across versions.
     * In v3.x the endpoint path/format is the same, but verify if you upgrade.
     */
    public function addLabel(int $conversationId, string $label): void
    {
        $conv = $this->getConversation($conversationId);
        $existing = $conv['labels'] ?? [];
        if (in_array($label, $existing, true)) {
            return; // already present
        }
        $existing[] = $label;

        // Chatwoot expects a JSON body with the complete labels array
        $this->api('POST', "/conversations/{$conversationId}/labels", [
            'labels' => $existing,
        ]);

        Logger::info("Label added", ['conversation_id' => $conversationId, 'label' => $label]);
    }

    /**
     * Set custom attributes on a conversation.
     * POST /conversations/{id}/custom_attributes with { "custom_attributes": { ... } }
     *
     * Chatwoot merges provided keys into existing custom_attributes.
     */
    public function setCustomAttributes(int $conversationId, array $attrs): void
    {
        $result = $this->api('POST', "/conversations/{$conversationId}/custom_attributes", [
            'custom_attributes' => $attrs,
        ]);
        Logger::info("Custom attributes set", ['conversation_id' => $conversationId, 'attrs' => $attrs]);
        Logger::debug("Custom attributes API response", [
            'conversation_id'       => $conversationId,
            'returned_custom_attrs' => $result['custom_attributes'] ?? '(missing)',
        ]);
    }

    /**
     * Assign a specific agent to a conversation.
     * POST /conversations/{id}/assignments with { "assignee_id": agent_id }
     */
    public function assignConversation(int $conversationId, int $agentId): void
    {
        $this->api('POST', "/conversations/{$conversationId}/assignments", [
            'assignee_id' => $agentId,
        ]);
        Logger::info("Conversation assigned", ['conversation_id' => $conversationId, 'agent_id' => $agentId]);
    }

    /**
     * Remove the assigned agent from a conversation (un-assign).
     *
     * Chatwoot API: POST /conversations/{id}/assignments
     * with { "assignee_id": null } to un-assign.
     *
     * NOTE (Chatwoot version): In v2.x/v3.x the assignments endpoint accepts
     * assignee_id=null to clear the assignment. If your version behaves
     * differently, adjust accordingly.
     */
    public function unassignConversation(int $conversationId): void
    {
        // Attempt to un-assign by setting assignee_id to null
        $url = $this->apiUrl("/conversations/{$conversationId}/assignments");
        $res = HttpClient::request('POST', $url, $this->authHeaders(), [
            'assignee_id' => null,
        ]);

        if ($res['status'] >= 400) {
            Logger::warn("Unassign may have failed", [
                'conversation_id' => $conversationId,
                'status'          => $res['status'],
            ]);
        } else {
            Logger::info("Conversation unassigned", ['conversation_id' => $conversationId]);
        }
    }

    /**
     * Send an outgoing message in a conversation.
     * POST /conversations/{id}/messages
     *
     * message_type: 1 = outgoing
     */
    public function sendOutgoingMessage(int $conversationId, string $text): array
    {
        return $this->api('POST', "/conversations/{$conversationId}/messages", [
            'content'      => $text,
            'message_type' => 'outgoing',
            'private'      => false,
        ]);
    }

    /**
     * Check if conversation is in "ticket/manual" mode.
     * Returns true if label=ticket or custom_attributes.handoff=true.
     */
    public function isTicketMode(int $conversationId, ?array $convData = null): bool
    {
        $conv = $convData ?? $this->getConversation($conversationId);

        $ticketLabel = Env::get('CHATWOOT_TICKET_LABEL', 'ticket');
        $labels = $conv['labels'] ?? [];
        if (in_array($ticketLabel, $labels, true)) {
            return true;
        }

        $ca = $conv['custom_attributes'] ?? [];
        if (isset($ca['handoff']) && ($ca['handoff'] === true || $ca['handoff'] === 'true')) {
            return true;
        }

        return false;
    }
}