<?php

namespace objects;

use classes\db;
use classes\object_property;
use classes\selfserve_schema_bootstrap;
use Exception;
use modules\selfserve\helpers\selfserve_lane_services;
use modules\selfserve\helpers\selfserve_task_gate_type;
use traits\db_object_t;

class department_selfserve_tasks_o extends db
{
    use db_object_t;

    /**
     * Canonical relationship model for self-serve entities:
     * - Conditions can be nested via `department_selfserve_conditions.condition_id` (parent condition id).
     * - Questions can optionally be gated by a condition via `department_selfserve_questions.condition_id` (parent condition id).
     * - Tasks can optionally be gated by a question. For backward compatibility this is stored in
     *   `department_selfserve_tasks.condition_id`, but semantically this is a question reference.
     */

    public object_property $department; // The department id
    public object_property $lane; // The lane id
    public object_property $product; // The product id
    public object_property $machine_type_id; // The reusable machine type id (nullable, preferred over department/lane/product)
    public object_property $condition_id; // Legacy column name: stores question id that gates this task (nullable)
    public object_property $gate_type; // Canonical gate type: ALWAYS|CONDITION|QUESTION
    public object_property $gate_ref_id; // Canonical gate reference id (nullable)
    public object_property $task; // The task
    public object_property $description; // The task description
    public object_property $order_priority; // The order priority of the task (lower numbers are shown first)
    public object_property $services; // The services that the task enables (json), this is used to enable machine wash.
    public object_property $buttons; // The buttons on the departments machine dynamic image that should be enabled by this task (json array of mapped button ids)
    public object_property $dynamic_images_vehicle_type; // The vehicle type selection override on the machine, used by dynamicimages - int or null if not applicable.
    public object_property $created_at;
    public object_property $updated_at;
    public object_property $deleted_at;

    public static function getLaneProducts(int $lane_id): array
    {
        global /** @var db $db */
        $db;
        // Sanitize the input
        $lane_id = (int)$lane_id;
        // Get the products for the lane
        $sql = "SELECT DISTINCT product FROM department_selfserve_tasks WHERE lane = $lane_id AND deleted_at IS NULL ORDER BY product DESC";
        $result = $db->query($sql);
        $products = [];
        while ($row = $db->fetch_assoc($result)) {
            $products[] = (int)$row['product'];
        }
        return $products;
    }


    public function structure(): void
    {
        selfserve_schema_bootstrap::ensureTables();
        $this->setTable('department_selfserve_tasks');
    }

    /**
     * Add a task
     * @param int $department The department id
     * @param int $lane The lane id
     * @param int $product The product id
     * @param int|null $question_id Optional question id that gates this task. Persisted in legacy `condition_id` column.
     * @param string $task The task text
     * @param string $description The task description
     * @param int $order_priority The order priority of the task (lower numbers are shown first)
     * @param selfserve_lane_services[]|string[]|null $services The services that the task enables (stored as JSON array of service names). May be an array of enum cases or names.
     * @param array<int|string>|string|null $buttons Optional buttons on the department's machine dynamic image to be enabled by this task (stored as JSON array of button IDs). Accepts program integers plus "reset" and "start".
     * @param int|null $dynamic_images_vehicle_type Optional vehicle type selection override for the machine UI. Integer >= 0 or null.
     * @return department_selfserve_tasks_o
     * @throws Exception If the object was not created successfully
     */
    public function add(
        int $department,
        int $lane,
        int $product,
        int|null $question_id,
        string $task,
        string $description,
        int $order_priority = 0,
        ?array $services = null,
        array|string|null $buttons = null,
        int|null $dynamic_images_vehicle_type = null,
        ?int $machine_type_id = null,
        ?selfserve_task_gate_type $gate_type = null,
        ?int $gate_ref_id = null,
    ): self
    {
        global /** @var db $db */
        $db;
        // Sanitize the input
        $department = (int)$department;
        $lane = (int)$lane;
        $product = (int)$product;
        if (!is_null($question_id)) {
            $question_id = (int)$question_id;
        }
        if (!is_null($machine_type_id)) {
            $machine_type_id = (int)$machine_type_id;
        }
        if (!is_null($gate_ref_id)) {
            $gate_ref_id = (int)$gate_ref_id;
        }
        $task = $db->escape_string($task);
        $description = $db->escape_string($description);
        $order_priority = (int)$order_priority;
        // If the services array is not null, validate and normalize to array of service names (strings)
        $services_names = null;
        if (!is_null($services)) {
            $services_names = [];
            foreach ($services as $service) {
                if ($service instanceof selfserve_lane_services) {
                    $services_names[] = $service->name; // store by name
                    continue;
                }
                if (is_string($service)) {
                    $name = strtoupper(trim($service));
                    $valid = false;
                    foreach (selfserve_lane_services::cases() as $case) {
                        if ($case->name === $name) {
                            $valid = true;
                            break;
                        }
                    }
                    if (!$valid) {
                        throw new Exception("Invalid service: " . $service);
                    }
                    $services_names[] = $name;
                    continue;
                }
                throw new Exception("Invalid service type");
            }
        }
        // Normalize/validate buttons
        $buttons_ids = null;
        if (!is_null($buttons)) {
            $buttons_ids = self::normalizeButtonsInput($buttons);
        }

        // Normalize/validate dynamic_images_vehicle_type (nullable, integer >= 0)
        if (!is_null($dynamic_images_vehicle_type)) {
            $dynamic_images_vehicle_type = (int)$dynamic_images_vehicle_type;
            if ($dynamic_images_vehicle_type < 0) {
                throw new Exception('dynamic_images_vehicle_type must be an integer >= 0');
            }
        }

        if ($gate_type === null) {
            $resolvedGate = self::resolveLegacyGateDefinition($question_id);
            $gate_type = $resolvedGate['gate_type'];
            $gate_ref_id = $resolvedGate['gate_ref_id'];
        } elseif ($gate_type === selfserve_task_gate_type::ALWAYS) {
            $gate_ref_id = null;
        } elseif ($gate_ref_id === null || $gate_ref_id <= 0) {
            throw new Exception('gate_ref_id must be provided for CONDITION and QUESTION task gate types');
        }

        // Add the object
        $tmp_id = self::add_object([
            'department' => $department,
            'lane' => $lane,
            'product' => $product,
            ...(!is_null($machine_type_id) ? ['machine_type_id' => $machine_type_id] : []),
            ...(!is_null($question_id) ? ['condition_id' => $question_id] : []), // Legacy column name; contains the gating question id
            'gate_type' => $gate_type->value,
            'gate_ref_id' => $gate_ref_id,
            'task' => $task,
            'description' => $description,
            'order_priority' => $order_priority,
            'services' => $services_names,
            'buttons' => $buttons_ids,
            ...(!is_null($dynamic_images_vehicle_type) ? ['dynamic_images_vehicle_type' => $dynamic_images_vehicle_type] : []),
        ]);
        $this->id = $tmp_id;
        self::getObjectProperties();
        self::objectChanged();
        return $this;
    }


    public function getObjectProperties(): void
    {
        $this->department = new object_property($this->table, $this->id, 'department', 'int', false);
        $this->lane = new object_property($this->table, $this->id, 'lane', 'int', false);
        $this->product = new object_property($this->table, $this->id, 'product', 'int', false);
        $this->machine_type_id = new object_property($this->table, $this->id, 'machine_type_id', 'int', false);
        $this->condition_id = new object_property($this->table, $this->id, 'condition_id', 'int', true);
        $this->gate_type = new object_property($this->table, $this->id, 'gate_type', 'string', false);
        $this->gate_ref_id = new object_property($this->table, $this->id, 'gate_ref_id', 'int', true);
        $this->task = new object_property($this->table, $this->id, 'task', 'string', false);
        $this->description = new object_property($this->table, $this->id, 'description', 'string', false);
        $this->order_priority = new object_property($this->table, $this->id, 'order_priority', 'int', false);
        $this->services = new object_property($this->table, $this->id, 'services', 'json', false);
        $this->buttons = new object_property($this->table, $this->id, 'buttons', 'json', false);
        $this->dynamic_images_vehicle_type = new object_property($this->table, $this->id, 'dynamic_images_vehicle_type', 'int', false);
        $this->created_at = new object_property($this->table, $this->id, 'created_at', 'timestamp', false);
        $this->updated_at = new object_property($this->table, $this->id, 'updated_at', 'timestamp', false);
        $this->deleted_at = new object_property($this->table, $this->id, 'deleted_at', 'timestamp', false);
    }

    public function objectChanged(): void
    {
        //TODO: Add cache invalidation
    }

    public function asArray(): array
    {
        return [
            'id' => (int)$this->id,
            'department' => (int)$this->department->value(),
            'lane' => (int)$this->lane->value(),
            'product' => (int)$this->product->value(),
            'machine_type_id' => is_null($this->machine_type_id->value()) ? null : (int)$this->machine_type_id->value(),
            'condition_id' => is_null($this->condition_id->value()) ? null : (int)$this->condition_id->value(),
            'gate_type' => (string)($this->gate_type->value() ?? selfserve_task_gate_type::ALWAYS->value),
            'gate_ref_id' => is_null($this->gate_ref_id->value()) ? null : (int)$this->gate_ref_id->value(),
            'task' => (string)$this->task->value(),
            'description' => (string)$this->description->value(),
            'order_priority' => (int)$this->order_priority->value(),
            'services' => (array)$this->services->value(),
            'buttons' => (array)$this->buttons->value(),
            'dynamic_images_vehicle_type' => (function($v){ return $v === null ? null : (int)$v; })($this->dynamic_images_vehicle_type->value()),
            // Timestamps
            'created_at' => (string)$this->created_at->value(),
            'updated_at' => (string)$this->updated_at->value(),
        ];
    }

    /**
     * Adapter for canonical naming.
     * @return int|null Question id that gates this task.
     */
    public function getQuestionId(): ?int
    {
        $value = $this->condition_id->value();
        return is_null($value) ? null : (int)$value;
    }

    /**
     * Adapter for canonical naming while persisting to legacy `condition_id` column.
     * @param int|null $question_id
     * @return void
     */
    public function setQuestionId(?int $question_id): void
    {
        $this->condition_id->set(is_null($question_id) ? null : (int)$question_id);
        $resolvedGate = self::resolveLegacyGateDefinition($question_id);
        $this->gate_type->set($resolvedGate['gate_type']->value);
        $this->gate_ref_id->set($resolvedGate['gate_ref_id']);
    }

    public function getTasksForMachineType(int $machineTypeId): array
    {
        return self::getFieldsWhere([
            'machine_type_id' => $machineTypeId,
            'deleted_at' => null,
        ], ['id', 'department', 'lane', 'product', 'machine_type_id', 'condition_id', 'gate_type', 'gate_ref_id', 'task', 'description', 'order_priority', 'services', 'buttons', 'dynamic_images_vehicle_type', 'created_at', 'updated_at']);
    }

    public function getLegacyTasksForLaneProduct(int $departmentId, int $laneId, int $productId): array
    {
        return self::getFieldsWhere([
            'department' => $departmentId,
            'lane' => $laneId,
            'product' => $productId,
            'deleted_at' => null,
        ], ['id', 'department', 'lane', 'product', 'machine_type_id', 'condition_id', 'gate_type', 'gate_ref_id', 'task', 'description', 'order_priority', 'services', 'buttons', 'dynamic_images_vehicle_type', 'created_at', 'updated_at']);
    }

    /**
     * Normalize external gate_type inputs.
     * @param mixed $input
     * @return selfserve_task_gate_type
     * @throws Exception
     */
    public static function normalizeGateTypeInput(mixed $input): selfserve_task_gate_type
    {
        if ($input instanceof selfserve_task_gate_type) {
            return $input;
        }
        if (is_string($input)) {
            $normalized = strtoupper(trim($input));
            $gateType = selfserve_task_gate_type::tryFrom($normalized);
            if ($gateType !== null) {
                return $gateType;
            }
        }
        throw new Exception('Invalid gate_type. Expected ALWAYS, CONDITION, or QUESTION.');
    }

    /**
     * Resolve a typed gate from legacy `condition_id` input.
     * @param int|null $legacyGateId
     * @return array{gate_type:selfserve_task_gate_type,gate_ref_id:int|null}
     */
    public static function resolveLegacyGateDefinition(?int $legacyGateId): array
    {
        if ($legacyGateId === null || $legacyGateId <= 0) {
            return [
                'gate_type' => selfserve_task_gate_type::ALWAYS,
                'gate_ref_id' => null,
            ];
        }

        $condition = (new department_selfserve_conditions_o())->select((int)$legacyGateId);
        if ($condition->exists()) {
            return [
                'gate_type' => selfserve_task_gate_type::CONDITION,
                'gate_ref_id' => (int)$legacyGateId,
            ];
        }

        return [
            'gate_type' => selfserve_task_gate_type::QUESTION,
            'gate_ref_id' => (int)$legacyGateId,
        ];
    }

    /**
     * Normalize input for dynamic_images_vehicle_type into a nullable non-negative integer.
     * Accepts int, string (numeric), null, or empty string (treated as null).
     * @param mixed $input
     * @return int|null
     * @throws Exception on invalid format or negative values
     */
    public static function normalizeVehicleTypeInput(mixed $input): ?int
    {
        if ($input === null) {
            return null;
        }
        if (is_string($input)) {
            $trim = trim($input);
            if ($trim === '' || strtolower($trim) === 'null') {
                return null;
            }
            if (ctype_digit($trim)) {
                $val = (int)$trim;
            } elseif (is_numeric($trim) && (int)$trim == $trim) {
                $val = (int)$trim;
            } else {
                throw new Exception('Invalid dynamic_images_vehicle_type value');
            }
        } elseif (is_int($input)) {
            $val = $input;
        } else {
            throw new Exception('Invalid dynamic_images_vehicle_type value');
        }
        if ($val < 0) {
            throw new Exception('dynamic_images_vehicle_type must be >= 0');
        }
        return $val;
    }
    /**
     * Normalize mixed input for buttons into an array of mapped button IDs.
     * Accepts:
     *  - array of ints/strings
     *  - JSON array string
     *  - comma-separated string
     * @param mixed $input
     * @return array<int|string>
     * @throws Exception
     */
    public static function normalizeButtonsInput(mixed $input): array
    {
        $raw = $input;
        if (is_string($raw)) {
            $decoded = json_decode($raw, true);
            if (json_last_error() === JSON_ERROR_NONE && is_array($decoded)) {
                $raw = $decoded;
            } else {
                $raw = array_filter(array_map(function ($s) { return trim((string)$s); }, explode(',', $raw)), fn($s) => $s !== '');
            }
        }
        if (!is_array($raw)) {
            throw new Exception('Invalid format for buttons. Expected array, JSON array, or comma-separated string of mapped button ids.');
        }
        $ids = [];
        foreach ($raw as $btn) {
            if (is_string($btn)) {
                $trimmed = trim($btn);
                $specialButton = strtolower($trimmed);
                if ($specialButton === 'reset' || $specialButton === 'start' || $specialButton === 'program_picker') {
                    $ids[] = $specialButton;
                    continue;
                }
            }
            if (is_int($btn)) {
                $val = $btn;
            } elseif (is_string($btn) && ctype_digit(trim($btn))) {
                $val = (int)trim($btn);
            } elseif (is_numeric($btn) && (int)$btn == $btn) {
                $val = (int)$btn;
            } else {
                throw new Exception('Invalid button id: ' . (is_scalar($btn) ? (string)$btn : gettype($btn)));
            }
            if ($val < 0) {
                throw new Exception('Button id must be >= 0: ' . $val);
            }
            $ids[] = $val;
        }
        // de-duplicate while preserving order
        $deduped = [];
        $seen = [];
        foreach ($ids as $id) {
            $key = (is_int($id) ? 'int:' : 'string:') . (string)$id;
            if (isset($seen[$key])) {
                continue;
            }
            $seen[$key] = true;
            $deduped[] = $id;
        }
        return $deduped;
    }
}