<?php

namespace MintyPHP\Tests\Module\Helpdesk\Service;

use MintyPHP\Module\Helpdesk\Service\CustomerEngagementService;
use PHPUnit\Framework\TestCase;

class CustomerEngagementServiceTest extends TestCase
{
    // Fixed "now" so tests are deterministic: 2026-06-25 12:00:00 UTC.
    private const NOW_TS = 1782475200;

    /**
     * @return array<string, mixed>
     */
    private static function ticket(
        string $no,
        string $customerNo,
        string $customerName,
        int $createdDaysAgo,
        ?int $lastActivityDaysAgo = null
    ): array {
        $createdTs = self::NOW_TS - ($createdDaysAgo * 86400);
        $activityTs = $lastActivityDaysAgo !== null
            ? self::NOW_TS - ($lastActivityDaysAgo * 86400)
            : $createdTs;

        return [
            'No' => $no,
            'Customer_No' => $customerNo,
            'Cust_Name' => $customerName,
            'Created_On' => gmdate('Y-m-d\TH:i:s\Z', $createdTs),
            'Last_Activity_Date' => gmdate('Y-m-d\TH:i:s\Z', $activityTs),
            'Ticket_State' => 'Offen',
        ];
    }

    public function testEmptyTicketsReturnsEmptyResult(): void
    {
        $result = CustomerEngagementService::buildEngagement([], 90, 60, self::NOW_TS);

        $this->assertSame(0, $result['summary']['total_customers']);
        $this->assertSame(0, $result['summary']['active']);
        $this->assertSame(0, $result['summary']['silent']);
        $this->assertSame([], $result['silent']);
        $this->assertSame([], $result['top_communication']);
    }

    public function testSkipsTicketsWithoutCustomerNo(): void
    {
        $tickets = [
            self::ticket('T1', '', 'No Customer', 5),
            self::ticket('T2', '10610', 'Valid', 5),
        ];

        $result = CustomerEngagementService::buildEngagement($tickets, 90, 60, self::NOW_TS);

        $this->assertSame(1, $result['summary']['total_customers']);
    }

    public function testAggregatesTicketCountsPerCustomer(): void
    {
        $tickets = [
            self::ticket('T1', '10610', 'Kunde A', 5),
            self::ticket('T2', '10610', 'Kunde A', 10),
            self::ticket('T3', '10620', 'Kunde B', 3),
        ];

        $result = CustomerEngagementService::buildEngagement($tickets, 90, 60, self::NOW_TS);

        $this->assertSame(2, $result['summary']['total_customers']);

        $top = $result['top_communication'];
        $byCustomer = [];
        foreach ($top as $row) {
            $byCustomer[$row['customer_no']] = $row;
        }
        $this->assertSame(2, $byCustomer['10610']['ticket_count_period']);
        $this->assertSame(1, $byCustomer['10620']['ticket_count_period']);
    }

    public function testActiveCustomerWithinThreshold(): void
    {
        // Last contact 10 days ago, threshold 60 => active.
        $tickets = [self::ticket('T1', '10610', 'Kunde A', 10)];

        $result = CustomerEngagementService::buildEngagement($tickets, 90, 60, self::NOW_TS);

        $this->assertSame(1, $result['summary']['active']);
        $this->assertSame(0, $result['summary']['silent']);
        $this->assertSame([], $result['silent']);
    }

    public function testSilentCustomerBeyondThreshold(): void
    {
        // Last contact 90 days ago, threshold 60 => silent.
        $tickets = [self::ticket('T1', '10610', 'Kunde A', 90)];

        $result = CustomerEngagementService::buildEngagement($tickets, 365, 60, self::NOW_TS);

        $this->assertSame(0, $result['summary']['active']);
        $this->assertSame(1, $result['summary']['silent']);
        $this->assertCount(1, $result['silent']);
        $this->assertSame('10610', $result['silent'][0]['customer_no']);
        $this->assertSame('silent', $result['silent'][0]['status']);
        $this->assertSame(90, $result['silent'][0]['days_since_contact']);
    }

    public function testLastContactUsesMostRecentActivity(): void
    {
        // Two tickets: one created 100 days ago but updated 5 days ago, one created 50 days ago.
        // Most recent activity is 5 days ago => active.
        $tickets = [
            self::ticket('T1', '10610', 'Kunde A', 100, 5),
            self::ticket('T2', '10610', 'Kunde A', 50, 50),
        ];

        $result = CustomerEngagementService::buildEngagement($tickets, 365, 60, self::NOW_TS);

        $this->assertSame(1, $result['summary']['active']);
        $row = $result['top_communication'][0];
        $this->assertSame(5, $row['days_since_contact']);
    }

    public function testSilentListSortedByLongestSilenceFirst(): void
    {
        $tickets = [
            self::ticket('T1', '10610', 'Recently Silent', 70),
            self::ticket('T2', '10620', 'Long Silent', 200),
            self::ticket('T3', '10630', 'Mid Silent', 120),
        ];

        $result = CustomerEngagementService::buildEngagement($tickets, 365, 60, self::NOW_TS);

        $order = array_column($result['silent'], 'customer_no');
        $this->assertSame(['10620', '10630', '10610'], $order);
    }

    public function testTopCommunicationExcludesCustomersWithNoPeriodActivity(): void
    {
        // Ticket older than the 30-day period => not counted in top list.
        $tickets = [
            self::ticket('T1', '10610', 'Active', 5),
            self::ticket('T2', '10620', 'Old', 100),
        ];

        $result = CustomerEngagementService::buildEngagement($tickets, 30, 60, self::NOW_TS);

        $tops = array_column($result['top_communication'], 'customer_no');
        $this->assertContains('10610', $tops);
        $this->assertNotContains('10620', $tops);
    }

    public function testIgnoresUninitializedBcDates(): void
    {
        // BC sentinel date 0001-01-01 must be treated as "no contact".
        $tickets = [[
            'No' => 'T1',
            'Customer_No' => '10610',
            'Cust_Name' => 'Kunde A',
            'Created_On' => '0001-01-01T00:00:00Z',
            'Last_Activity_Date' => '0001-01-01T00:00:00Z',
            'Ticket_State' => 'Offen',
        ]];

        $result = CustomerEngagementService::buildEngagement($tickets, 90, 60, self::NOW_TS);

        $this->assertSame(1, $result['summary']['no_contact_ever']);
        $this->assertNull($result['silent'][0]['last_contact_ts']);
        $this->assertSame('no_contact_ever', $result['silent'][0]['status']);
    }

    public function testMetaReflectsInputs(): void
    {
        $result = CustomerEngagementService::buildEngagement([], 180, 45, self::NOW_TS, true);

        $this->assertSame(180, $result['meta']['period_days']);
        $this->assertSame(45, $result['meta']['inactivity_days']);
        $this->assertTrue($result['meta']['truncated']);
        $this->assertSame('medium', $result['meta']['confidence']);
        $this->assertSame(self::NOW_TS, $result['meta']['generated_ts']);
    }
}