<?php

declare(strict_types=1);

namespace Infrastructure\Persistence;

// @responsibility: Persistenz für Task-Ergebnisse (AI-Responses, Token-Usage)

use Domain\Entity\TaskResult;

class TaskResultRepository
{
    private \PDO $pdo;

    public function __construct(\PDO $pdo)
    {
        $this->pdo = $pdo;
    }

    public function find(int $id): ?TaskResult
    {
        $stmt = $this->pdo->prepare('SELECT * FROM task_results WHERE id = :id');
        $stmt->execute(['id' => $id]);
        $row = $stmt->fetch();

        return $row !== false ? TaskResult::fromArray($row) : null;
    }

    public function findByTaskId(int $taskId): array
    {
        $stmt = $this->pdo->prepare(
            'SELECT * FROM task_results WHERE task_id = :task_id ORDER BY created_at DESC'
        );
        $stmt->execute(['task_id' => $taskId]);

        $results = [];
        while ($row = $stmt->fetch()) {
            $results[] = TaskResult::fromArray($row);
        }

        return $results;
    }

    public function findByAssignmentId(int $assignmentId): array
    {
        $stmt = $this->pdo->prepare(
            'SELECT * FROM task_results WHERE assignment_id = :assignment_id ORDER BY created_at DESC'
        );
        $stmt->execute(['assignment_id' => $assignmentId]);

        $results = [];
        while ($row = $stmt->fetch()) {
            $results[] = TaskResult::fromArray($row);
        }

        return $results;
    }

    public function save(TaskResult $result): int
    {
        $sql = 'INSERT INTO task_results (
            task_id, assignment_id, executor, executor_type, model_name,
            request, response, request_timestamp, response_timestamp,
            duration_ms, tokens_input, tokens_output, tokens_total,
            cost_usd, status, error_message, created_at
        ) VALUES (
            :task_id, :assignment_id, :executor, :executor_type, :model_name,
            :request, :response, :request_timestamp, :response_timestamp,
            :duration_ms, :tokens_input, :tokens_output, :tokens_total,
            :cost_usd, :status, :error_message, :created_at
        )';

        $stmt = $this->pdo->prepare($sql);
        $data = $result->toArray();

        $stmt->execute([
            'task_id' => $data['task_id'],
            'assignment_id' => $data['assignment_id'],
            'executor' => $data['executor'],
            'executor_type' => $data['executor_type'],
            'model_name' => $data['model_name'],
            'request' => $data['request'],
            'response' => $data['response'],
            'request_timestamp' => $data['request_timestamp'],
            'response_timestamp' => $data['response_timestamp'],
            'duration_ms' => $data['duration_ms'],
            'tokens_input' => $data['tokens_input'],
            'tokens_output' => $data['tokens_output'],
            'tokens_total' => $data['tokens_total'],
            'cost_usd' => $data['cost_usd'],
            'status' => $data['status'],
            'error_message' => $data['error_message'],
            'created_at' => $data['created_at'],
        ]);

        return (int) $this->pdo->lastInsertId();
    }

    public function getTokenStatistics(?int $taskId = null): array
    {
        $where = $taskId !== null ? 'WHERE task_id = :task_id' : '';
        $params = $taskId !== null ? ['task_id' => $taskId] : [];

        $sql = "SELECT
            COUNT(*) as total_results,
            SUM(tokens_input) as total_tokens_input,
            SUM(tokens_output) as total_tokens_output,
            SUM(tokens_total) as total_tokens,
            SUM(cost_usd) as total_cost,
            AVG(duration_ms) as avg_duration_ms,
            SUM(CASE WHEN status = 'success' THEN 1 ELSE 0 END) as successful,
            SUM(CASE WHEN status = 'error' THEN 1 ELSE 0 END) as failed
        FROM task_results {$where}";

        $stmt = $this->pdo->prepare($sql);
        $stmt->execute($params);

        return $stmt->fetch();
    }

    public function getModelUsage(): array
    {
        $sql = 'SELECT
            model_name,
            executor_type,
            COUNT(*) as usage_count,
            SUM(tokens_total) as total_tokens,
            SUM(cost_usd) as total_cost,
            AVG(duration_ms) as avg_duration
        FROM task_results
        WHERE model_name IS NOT NULL
        GROUP BY model_name, executor_type
        ORDER BY usage_count DESC';

        $stmt = $this->pdo->query($sql);

        return $stmt->fetchAll();
    }
}