<?php
/**
 * Odoo JSON-RPC API client.
 *
 * Communicates with Odoo 19 via the /jsonrpc endpoint using the
 * "common" (authenticate) and "object" (execute_kw) services.
 * Uses WordPress's built-in HTTP API – no Composer required.
 */

defined( 'ABSPATH' ) || exit;

class WooDoo_API {

    private string  $url;
    private string  $db;
    private string  $username;
    private string  $api_key;
    private ?int    $uid = null;

    /** Cache results for one minute to reduce round-trips */
    private const CACHE_TTL = 60;

    public function __construct(
        string $url,
        string $db,
        string $username,
        string $api_key
    ) {
        $this->url      = $url;
        $this->db       = $db;
        $this->username = $username;
        $this->api_key  = $api_key;
    }

    // ── Low-level JSON-RPC ────────────────────────────────────────────────

    /**
     * POST to /jsonrpc.
     *
     * @param  string $service  "common" | "object"
     * @param  string $method   e.g. "authenticate" | "execute_kw"
     * @param  array  $args     positional arguments
     * @return mixed            decoded result or WP_Error
     */
    public function jsonrpc( string $service, string $method, array $args ): mixed {
        $body = wp_json_encode( [
            'jsonrpc' => '2.0',
            'method'  => 'call',
            'id'      => wp_rand( 1, 999999999 ),
            'params'  => [
                'service' => $service,
                'method'  => $method,
                'args'    => $args,
            ],
        ] );

        $response = wp_remote_post(
            $this->url . '/jsonrpc',
            [
                'headers'   => [ 'Content-Type' => 'application/json' ],
                'body'      => $body,
                'timeout'   => 30,
                'sslverify' => apply_filters( 'woodoo_ssl_verify', true ),
            ]
        );

        if ( is_wp_error( $response ) ) {
            return $response;
        }

        $data = json_decode( wp_remote_retrieve_body( $response ), true );

        if ( isset( $data['error'] ) ) {
            $msg = $data['error']['data']['message']
                ?? $data['error']['message']
                ?? 'Unknown Odoo error';
            return new WP_Error( 'odoo_error', $msg, $data['error'] );
        }

        return $data['result'] ?? null;
    }

    // ── Authentication ────────────────────────────────────────────────────

    /**
     * Authenticate and cache the uid for this request lifecycle.
     */
    public function authenticate(): ?int {
        if ( $this->uid ) return $this->uid;

        $result = $this->jsonrpc( 'common', 'authenticate', [
            $this->db,
            $this->username,
            $this->api_key,
            [],
        ] );

        if ( is_wp_error( $result ) || ! is_int( $result ) || $result <= 0 ) {
            return null;
        }

        $this->uid = $result;
        return $this->uid;
    }

    // ── ORM execute_kw wrapper ────────────────────────────────────────────

    /**
     * Call any ORM method via execute_kw.
     *
     * @param  string $model   e.g. 'res.partner'
     * @param  string $method  e.g. 'search_read'
     * @param  array  $args    positional args (list of lists usually)
     * @param  array  $kwargs  keyword args (fields, limit, offset, etc.)
     */
    public function execute_kw( string $model, string $method, array $args = [], array $kwargs = [] ): mixed {
        $uid = $this->authenticate();
        if ( ! $uid ) {
            return new WP_Error( 'woodoo_auth', 'Could not authenticate with Odoo.' );
        }

        return $this->jsonrpc( 'object', 'execute_kw', [
            $this->db,
            $uid,
            $this->api_key,
            $model,
            $method,
            $args,
            $kwargs,
        ] );
    }

    // ── Convenience helpers ───────────────────────────────────────────────

    public function search_read(
        string $model,
        array  $domain  = [],
        array  $fields  = [],
        int    $limit   = 0,
        int    $offset  = 0,
        string $order   = ''
    ): array {
        $kwargs = [ 'fields' => $fields ];
        if ( $limit  > 0  ) $kwargs['limit']  = $limit;
        if ( $offset > 0  ) $kwargs['offset'] = $offset;
        if ( $order !== '' ) $kwargs['order']  = $order;

        $result = $this->execute_kw( $model, 'search_read', [ $domain ], $kwargs );
        return is_array( $result ) ? $result : [];
    }

    public function search(
        string $model,
        array  $domain = [],
        int    $limit  = 0,
        int    $offset = 0,
        string $order  = ''
    ): array {
        $kwargs = [];
        if ( $limit  > 0  ) $kwargs['limit']  = $limit;
        if ( $offset > 0  ) $kwargs['offset'] = $offset;
        if ( $order !== '' ) $kwargs['order']  = $order;

        $result = $this->execute_kw( $model, 'search', [ $domain ], $kwargs );
        return is_array( $result ) ? $result : [];
    }

    public function read( string $model, array $ids, array $fields = [] ): array {
        $kwargs = $fields ? [ 'fields' => $fields ] : [];
        $result = $this->execute_kw( $model, 'read', [ $ids ], $kwargs );
        return is_array( $result ) ? $result : [];
    }

    public function create( string $model, array $values ): ?int {
        $result = $this->execute_kw( $model, 'create', [ $values ] );
        return is_int( $result ) ? $result : null;
    }

    public function write( string $model, array $ids, array $values ): bool {
        $result = $this->execute_kw( $model, 'write', [ $ids, $values ] );
        return $result === true;
    }

    public function search_count( string $model, array $domain = [] ): int {
        $result = $this->execute_kw( $model, 'search_count', [ $domain ] );
        return is_int( $result ) ? $result : 0;
    }

    public function unlink( string $model, array $ids ): bool {
        $result = $this->execute_kw( $model, 'unlink', [ $ids ] );
        return $result === true;
    }

    // ── Partner helpers ───────────────────────────────────────────────────

    /**
     * Find a partner by email or create one.
     * Returns the Odoo partner ID.
     */
    public function find_or_create_partner( string $email, string $name, array $extra = [] ): ?int {
        $found = $this->search( 'res.partner', [ [ 'email', '=', $email ] ], 1 );
        if ( ! empty( $found ) ) {
            return (int) $found[0];
        }

        return $this->create( 'res.partner', array_merge( [
            'name'  => $name,
            'email' => $email,
        ], $extra ) );
    }

    // ── Product helpers ───────────────────────────────────────────────────

    /**
     * Find a product.product by its SKU (default_code).
     * Returns product ID or null if not found.
     */
    public function find_product_by_sku( string $sku ): ?int {
        if ( empty( $sku ) ) return null;
        $found = $this->search( 'product.product', [ [ 'default_code', '=', $sku ] ], 1 );
        return ! empty( $found ) ? (int) $found[0] : null;
    }

    // ── Diagnostics ───────────────────────────────────────────────────────

    /**
     * Test connectivity and credentials.
     * Returns ['success' => bool, 'message' => string, 'version' => string|null]
     */
    public function test_connection(): array {
        // Version check (no auth needed)
        $version = $this->jsonrpc( 'common', 'version', [] );
        if ( is_wp_error( $version ) ) {
            return [
                'success' => false,
                'message' => 'Cannot reach Odoo: ' . $version->get_error_message(),
                'version' => null,
            ];
        }

        $ver_str = $version['server_version'] ?? 'unknown';

        // Try authenticate
        $uid = $this->authenticate();
        if ( ! $uid ) {
            return [
                'success' => false,
                'message' => "Reached Odoo {$ver_str} but authentication failed. Check username / API key.",
                'version' => $ver_str,
            ];
        }

        return [
            'success' => true,
            'message' => "Connected to Odoo {$ver_str} as UID {$uid}.",
            'version' => $ver_str,
        ];
    }
}