<?php

namespace App\Services;

use App\Models\LoginActivityModel;
use App\Models\UserModel;

class AdministratorDashboardService
{
    protected $db;
    protected $userModel;
    protected $loginActivityModel;
    protected string $schoolYear = '';
    protected string $semester = '';

    public function __construct(
        \CodeIgniter\Database\BaseConnection $db,
        UserModel $userModel,
        LoginActivityModel $loginActivityModel
    ) {
        $this->db = $db;
        $this->userModel = $userModel;
        $this->loginActivityModel = $loginActivityModel;
    }

public function metrics(string $schoolYear, string $semester): array
{
    $this->schoolYear = $schoolYear;
    $this->semester = $semester;
    $recentActivities = $this->loginActivityModel->getLastActivities(4);
    if (!is_array($recentActivities)) {
        $recentActivities = [];
    }

    $totalAdmins = (int) ($this->userModel->countAdminsBySchoolYear($this->schoolYear) ?? 0);

    $teachers = $this->userModel->getUsersByRole('teacher');
    $totalTeachers = $this->countUniqueEntities($teachers);

    $teacherAssistants = $this->userModel->getUsersByRole('teacher_assistant');
    $totalTeacherAssistants = $this->countUniqueEntities($teacherAssistants);

    $totalParents = $this->countParentsWithEnrolledStudents($this->schoolYear);

    // Count only students that have a class assigned and exist in student_class for the current school year
    $totalStudents = (int) (
        $this->db->table('student_class')
            ->select('COUNT(DISTINCT student_class.student_id) AS cnt')
            ->join('students', 'students.id = student_class.student_id', 'inner')
            ->where('student_class.school_year', $this->schoolYear)
            ->where('student_class.class_section_id IS NOT NULL', null, false)
            ->where('students.is_active', 1)
            ->get()
            ->getRow('cnt')
        ?? 0
    );

    return [
        'counts' => [
            'students'          => $totalStudents,
            'teachers'          => $totalTeachers,
            'teacherAssistants' => $totalTeacherAssistants,
            'admins'            => $totalAdmins,
            'parents'           => $totalParents,
        ],
        'recentActivities' => array_map(static function ($activity) {
            if (!is_array($activity)) {
                return [];
            }
            return [
                'login_time' => $activity['login_time'] ?? null,
                'email'      => $activity['email'] ?? null,
            ];
        }, $recentActivities),
        'meta' => [
            'schoolYear' => $this->schoolYear,
            'semester'   => $this->semester,
        ],
    ];
}

private function countUniqueEntities($rows): int
{
    if (!is_array($rows) || $rows === []) {
        return 0;
    }

    $ids = [];
    foreach ($rows as $row) {
        if (!is_array($row)) {
            continue;
        }
        if (isset($row['id'])) {
            $ids[] = (int) $row['id'];
            continue;
        }
        if (isset($row['user_id'])) {
            $ids[] = (int) $row['user_id'];
        }
    }

    return count(array_unique($ids));
}

private function countParentsWithEnrolledStudents(string $schoolYear): int
{
    $schoolYear = trim($schoolYear);
    if ($schoolYear === '') {
        return 0;
    }

    return (int) (
        $this->db->table('students')
            ->select('COUNT(DISTINCT students.parent_id) AS cnt')
            ->join('student_class', 'student_class.student_id = students.id', 'inner')
            ->join('users', 'users.id = students.parent_id', 'inner')
            ->join('user_roles', 'user_roles.user_id = users.id', 'inner')
            ->join('roles', 'roles.id = user_roles.role_id', 'inner')
            ->where('student_class.school_year', $schoolYear)
            ->where('student_class.class_section_id IS NOT NULL', null, false)
            ->where('students.is_active', 1)
            ->where('students.parent_id IS NOT NULL', null, false)
            ->where('students.parent_id >', 0)
            ->where('user_roles.deleted_at', null)
            ->groupStart()
                ->where('LOWER(roles.name)', 'parent')
                ->orWhere('roles.slug', 'parent')
            ->groupEnd()
            ->get()
            ->getRow('cnt')
        ?? 0
    );
}

public function search(string $query): array
{
    $q = trim($query);

    if ($q === '') {
        return [
            'query'       => '',
            'results'     => [],
            'scope_used'  => 'unscoped-raw',
            'scope_label' => 'all years/semesters (raw)',
            'total_found' => 0,
        ];
    }

    $db = $this->db;

    // 1) Tokenize input: split by whitespace and punctuation, keep meaningful pieces
    $rawTokens = preg_split('/[,\s]+/u', $q, -1, PREG_SPLIT_NO_EMPTY) ?: [];
    $tokens = array_values(array_filter(array_map('trim', $rawTokens)));
    if ($tokens === []) {
        return [
            'query'       => $q,
            'results'     => [],
            'scope_used'  => 'unscoped-merged',
            'scope_label' => 'all years/semesters (merged)',
            'total_found' => 0,
        ];
    }

    // 2) Build phone variants for any token that looks numeric-ish
    $phoneMap = []; // token => variants[]
    foreach ($tokens as $t) {
        $digits = preg_replace('/\D+/', '', $t);
        if ($digits === '') {
            continue;
        }

        $v = [];
        if (strlen($digits) >= 7) {
            // base forms
            $v[] = $digits;
            if (strlen($digits) === 10) {
                $v[] = sprintf('(%s)-%s-%s', substr($digits, 0, 3), substr($digits, 3, 3), substr($digits, 6));
                $v[] = sprintf('%s-%s-%s', substr($digits, 0, 3), substr($digits, 3, 3), substr($digits, 6));
                $v[] = sprintf('%s %s %s', substr($digits, 0, 3), substr($digits, 3, 3), substr($digits, 6));
                // country-code forms
                $v[] = '1' . $digits;
                $v[] = '+1' . $digits;
                $v[] = '+1 ' . sprintf('(%s) %s-%s', substr($digits, 0, 3), substr($digits, 3, 3), substr($digits, 6));
                $v[] = '+1-' . sprintf('%s-%s-%s', substr($digits, 0, 3), substr($digits, 3, 3), substr($digits, 6));
            } elseif (strlen($digits) === 11 && str_starts_with($digits, '1')) {
                $ten = substr($digits, 1);
                $v[] = $ten;
                $v[] = sprintf('(%s)-%s-%s', substr($ten, 0, 3), substr($ten, 3, 3), substr($ten, 6));
                $v[] = sprintf('%s-%s-%s', substr($ten, 0, 3), substr($ten, 3, 3), substr($ten, 6));
                $v[] = sprintf('%s %s %s', substr($ten, 0, 3), substr($ten, 3, 3), substr($ten, 6));
                $v[] = '+1' . $ten;
                $v[] = '+1 ' . sprintf('(%s) %s-%s', substr($ten, 0, 3), substr($ten, 3, 3), substr($ten, 6));
                $v[] = '+1-' . sprintf('%s-%s-%s', substr($ten, 0, 3), substr($ten, 3, 3), substr($ten, 6));
            } else {
                // 7-9 digits: keep as-is (partial phone fragment)
                $v[] = $digits;
            }
        }
        if (!empty($v)) {
            $phoneMap[$t] = array_values(array_unique($v));
        }
    }

    // Helper: ( token1 AND token2 AND ... ), each token may match ANY of $columns,
    // and phone variants are only applied to the provided $phoneCols for THIS table.
    $applyMultiTokenLike = function ($qb, array $columns, array $tokens, array $phoneCols = []) use ($phoneMap) {
        foreach ($tokens as $t) {
            $qb->groupStart(); // OR across columns for this token
            foreach ($columns as $i => $col) {
                if ($i === 0) {
                    $qb->like($col, $t);
                } else {
                    $qb->orLike($col, $t);
                }
            }
            if (!empty($phoneMap[$t]) && !empty($phoneCols)) {
                foreach ($phoneMap[$t] as $pv) {
                    foreach ($phoneCols as $pcol) {
                        $qb->orLike($pcol, $pv);
                    }
                }
            }
            $qb->groupEnd();
        }
        return $qb;
    };

    // ===== RAW UNscoped searches (flat arrays) =====

    // USERS (phone col: cellphone)
    $uCols = ['firstname', 'lastname', 'email', 'cellphone', 'school_id', 'city', 'state'];
    $uQB = $db->table('users')
        ->select('id, firstname, lastname, email, cellphone, school_id, city, state');
    $applyMultiTokenLike($uQB, $uCols, $tokens, ['cellphone']);
    $users = $uQB->limit(150)->get()->getResultArray();

    // STUDENTS (no phone column to search)
    $sCols = ['firstname', 'lastname', 'school_id', 'rfid_tag', 'dob', 'gender'];
    $sQB = $db->table('students')
        ->select('id, parent_id, school_id, firstname, lastname, dob, gender, rfid_tag');
    $applyMultiTokenLike($sQB, $sCols, $tokens, []);
    $students = $sQB->limit(150)->get()->getResultArray();

    // PARENTS (phone col: secondparent_phone)
    $pCols = ['secondparent_firstname', 'secondparent_lastname', 'secondparent_email', 'secondparent_phone'];
    $pQB = $db->table('parents')
        ->select('id, firstparent_id, secondparent_firstname, secondparent_lastname, secondparent_email, secondparent_phone');
    $applyMultiTokenLike($pQB, $pCols, $tokens, ['secondparent_phone']);
    foreach ($tokens as $t) {
        if (ctype_digit($t)) {
            $pQB->orWhere('firstparent_id', (int) $t)->orWhere('id', (int) $t);
        }
    }
    $parents = $pQB->limit(150)->get()->getResultArray();

    // STAFF (phone col: phone)
    $stCols = ['firstname', 'lastname', 'email', 'role_name', 'phone'];
    $stQB = $db->table('staff')
        ->select('id, user_id, firstname, lastname, email, phone, role_name, active_role');
    $applyMultiTokenLike($stQB, $stCols, $tokens, ['phone']);
    $staff = $stQB->limit(150)->get()->getResultArray();

    // EMERGENCY CONTACTS (phone col: cellphone)
    $ecCols = ['emergency_contact_name', 'relation', 'email', 'cellphone'];
    $ecQB = $db->table('emergency_contacts')
        ->select('id, parent_id, emergency_contact_name, relation, cellphone, email');
    $applyMultiTokenLike($ecQB, $ecCols, $tokens, ['cellphone']);
    $emergency = $ecQB->limit(150)->get()->getResultArray();

    $results = $this->mergeSearchResults($users, $students, $parents, $staff, $emergency);

    return [
        'query'       => $q,
        'results'     => $results,
        'scope_used'  => 'unscoped-merged',
        'scope_label' => 'all years/semesters (merged, tokenized)',
        'total_found' => count($results),
    ];
}

private function mergeSearchResults(array $users, array $students, array $parents, array $staff, array $emergency): array
{
    $bundles = [];
    $userIds = [];

    $ensureBundle = static function (int $userId) use (&$bundles, &$userIds): void {
        if ($userId <= 0) {
            return;
        }

        if (!isset($bundles[$userId])) {
            $bundles[$userId] = [
                'user'               => null,
                'students'           => [],
                'parents'            => [],
                'staff'              => [],
                'emergency_contacts' => [],
            ];
        }

        $userIds[$userId] = $userId;
    };

    foreach ($users as $user) {
        $userId = (int) ($user['id'] ?? 0);
        $ensureBundle($userId);
        if ($userId > 0) {
            $bundles[$userId]['user'] = $user;
        }
    }

    foreach ($students as $student) {
        $parentId = (int) ($student['parent_id'] ?? 0);
        $ensureBundle($parentId);
        if ($parentId > 0) {
            $bundles[$parentId]['students'][(int) ($student['id'] ?? 0)] = $student;
        }
    }

    foreach ($parents as $parent) {
        $firstParentId = (int) ($parent['firstparent_id'] ?? 0);
        $ensureBundle($firstParentId);
        if ($firstParentId > 0) {
            $bundles[$firstParentId]['parents'][(int) ($parent['id'] ?? 0)] = $parent;
        }
    }

    foreach ($staff as $staffRow) {
        $userId = (int) ($staffRow['user_id'] ?? 0);
        $ensureBundle($userId);
        if ($userId > 0) {
            $bundles[$userId]['staff'][(int) ($staffRow['id'] ?? 0)] = $staffRow;
        }
    }

    foreach ($emergency as $emergencyRow) {
        $parentId = (int) ($emergencyRow['parent_id'] ?? 0);
        $ensureBundle($parentId);
        if ($parentId > 0) {
            $bundles[$parentId]['emergency_contacts'][(int) ($emergencyRow['id'] ?? 0)] = $emergencyRow;
        }
    }

    if ($userIds === []) {
        return [];
    }

    $this->hydrateSearchBundles($bundles, array_values($userIds));

    $results = array_values($bundles);
    usort($results, static function (array $a, array $b): int {
        $aUser = $a['user'] ?? [];
        $bUser = $b['user'] ?? [];
        $aName = trim((string) ($aUser['lastname'] ?? '') . ' ' . (string) ($aUser['firstname'] ?? ''));
        $bName = trim((string) ($bUser['lastname'] ?? '') . ' ' . (string) ($bUser['firstname'] ?? ''));

        return strcasecmp($aName, $bName);
    });

    return $results;
}

private function hydrateSearchBundles(array &$bundles, array $userIds): void
{
    $userRows = $this->db->table('users')
        ->select('id, firstname, lastname, email, cellphone, school_id, city, state')
        ->whereIn('id', $userIds)
        ->get()
        ->getResultArray();

    foreach ($userRows as $user) {
        $userId = (int) ($user['id'] ?? 0);
        if ($userId > 0 && isset($bundles[$userId]) && empty($bundles[$userId]['user'])) {
            $bundles[$userId]['user'] = $user;
        }
    }

    $studentRows = $this->db->table('students')
        ->select('id, parent_id, school_id, firstname, lastname, dob, gender, rfid_tag, is_active')
        ->whereIn('parent_id', $userIds)
        ->orderBy('lastname', 'ASC')
        ->orderBy('firstname', 'ASC')
        ->get()
        ->getResultArray();

    foreach ($studentRows as $student) {
        $parentId = (int) ($student['parent_id'] ?? 0);
        if ($parentId > 0 && isset($bundles[$parentId])) {
            $bundles[$parentId]['students'][(int) ($student['id'] ?? 0)] = $student;
        }
    }

    $parentRows = $this->db->table('parents')
        ->select('id, firstparent_id, secondparent_firstname, secondparent_lastname, secondparent_email, secondparent_phone')
        ->whereIn('firstparent_id', $userIds)
        ->get()
        ->getResultArray();

    foreach ($parentRows as $parent) {
        $firstParentId = (int) ($parent['firstparent_id'] ?? 0);
        if ($firstParentId > 0 && isset($bundles[$firstParentId])) {
            $bundles[$firstParentId]['parents'][(int) ($parent['id'] ?? 0)] = $parent;
        }
    }

    $staffRows = $this->db->table('staff')
        ->select('id, user_id, firstname, lastname, email, phone, role_name, active_role')
        ->whereIn('user_id', $userIds)
        ->get()
        ->getResultArray();

    foreach ($staffRows as $staffRow) {
        $userId = (int) ($staffRow['user_id'] ?? 0);
        if ($userId > 0 && isset($bundles[$userId])) {
            $bundles[$userId]['staff'][(int) ($staffRow['id'] ?? 0)] = $staffRow;
        }
    }

    $emergencyRows = $this->db->table('emergency_contacts')
        ->select('id, parent_id, emergency_contact_name, relation, cellphone, email')
        ->whereIn('parent_id', $userIds)
        ->get()
        ->getResultArray();

    foreach ($emergencyRows as $emergencyRow) {
        $parentId = (int) ($emergencyRow['parent_id'] ?? 0);
        if ($parentId > 0 && isset($bundles[$parentId])) {
            $bundles[$parentId]['emergency_contacts'][(int) ($emergencyRow['id'] ?? 0)] = $emergencyRow;
        }
    }

    foreach ($bundles as &$bundle) {
        $bundle['students'] = array_values($bundle['students']);
        $bundle['parents'] = array_values($bundle['parents']);
        $bundle['staff'] = array_values($bundle['staff']);
        $bundle['emergency_contacts'] = array_values($bundle['emergency_contacts']);
    }
    unset($bundle);
}
}