<?php

namespace App\Http\Controllers\Api;

use App\Models\BadgePrintLog;
use App\Models\ClassSection;
use App\Models\Configuration;
use App\Models\SemesterScore;
use App\Models\StudentClass;
use App\Models\Student;
use App\Models\TeacherClass;
use App\Models\User;
use Carbon\Carbon;
use Illuminate\Http\JsonResponse;
use Illuminate\Support\Facades\DB;
use Illuminate\Support\Facades\Log;
use Symfony\Component\HttpFoundation\Response;
use Symfony\Component\HttpFoundation\StreamedResponse;

class PrintablesReportsController extends BaseApiController
{
    protected Student $student;
    protected ClassSection $classSection;
    protected Configuration $config;
    protected BadgePrintLog $badgePrintLog;
    protected SemesterScore $semesterScore;
    protected StudentClass $studentClass;
    protected TeacherClass $teacherClass;
    protected User $user;
    protected string $schoolYear;
    protected string $semester;

    public function __construct()
    {
        parent::__construct();
        $this->student = model(Student::class);
        $this->classSection = model(ClassSection::class);
        $this->config = model(Configuration::class);
        $this->badgePrintLog = model(BadgePrintLog::class);
        $this->semesterScore = model(SemesterScore::class);
        $this->studentClass = model(StudentClass::class);
        $this->teacherClass = model(TeacherClass::class);
        $this->user = model(User::class);
        $this->schoolYear = (string) ($this->config->getConfig('school_year') ?? '');
        $this->semester = (string) ($this->config->getConfig('semester') ?? '');
    }

    /**
     * GET /api/v1/printables/report-card-meta
     * Get report card metadata for UI hydration
     */
    public function reportCardMeta(): JsonResponse
    {
        try {
            $year = trim((string) ($this->request->getGet('school_year') ?? $this->schoolYear ?? ''));
            $sem = trim((string) ($this->request->getGet('semester') ?? $this->semester ?? ''));

            if ($year === '') {
                // Fallback to latest present in classSection or semester_score
                $yr = DB::table('classSection')
                    ->select('school_year')
                    ->orderBy('school_year', 'DESC')
                    ->first();
                $year = (string) ($yr->school_year ?? '');
            }

            // Build schoolYears from classSection and semester_scores
            $schoolYears = [];
            try {
                $q1 = DB::table('classSection')
                    ->select(DB::raw('DISTINCT school_year'))
                    ->whereNotNull('school_year')
                    ->orderBy('school_year', 'DESC')
                    ->pluck('school_year')
                    ->map(fn($r) => (string) $r)
                    ->filter()
                    ->values()
                    ->toArray();
                $schoolYears = $q1;
            } catch (\Throwable $e) {
                // ignore
            }

            try {
                $q2 = DB::table('semester_scores')
                    ->select(DB::raw('DISTINCT school_year'))
                    ->whereNotNull('school_year')
                    ->orderBy('school_year', 'DESC')
                    ->pluck('school_year')
                    ->map(fn($r) => (string) $r)
                    ->filter()
                    ->toArray();

                foreach ($q2 as $val) {
                    if ($val !== '' && !in_array($val, $schoolYears, true)) {
                        $schoolYears[] = $val;
                    }
                }
            } catch (\Throwable $e) {
                // ignore
            }

            rsort($schoolYears);

            // Semesters available for the selected year
            $semesters = [];
            try {
                $rs = DB::table('semester_scores')
                    ->select(DB::raw('DISTINCT semester'))
                    ->where('school_year', $year)
                    ->whereNotNull('semester')
                    ->orderBy('semester', 'ASC')
                    ->pluck('semester')
                    ->map(fn($r) => (string) $r)
                    ->filter()
                    ->values()
                    ->toArray();
                $semesters = $rs;
            } catch (\Throwable $e) {
                // ignore
            }

            if (empty($semesters)) {
                // Provide a sensible default list
                $defaults = array_filter([(string) ($this->semester ?? ''), 'Fall', 'Spring'], fn($v) => $v !== '');
                $semesters = array_values(array_unique($defaults));
            }

            if ($sem === '' && !empty($semesters)) {
                $sem = $semesters[0];
            }

            // Students: prefer those with scores in selected year (+semester if provided); fallback to all
            $students = [];
            try {
                $stuRows = DB::table('semester_scores ss')
                    ->select(DB::raw('DISTINCT s.id, s.firstname, s.lastname'))
                    ->join('students s', 's.id', '=', 'ss.student_id')
                    ->where('ss.school_year', $year)
                    ->where(function ($query) use ($sem) {
                        if ($sem !== '') {
                            $query->where('ss.semester', $sem);
                        }
                    })
                    ->orderBy('s.lastname', 'ASC')
                    ->get()
                    ->toArray();

                if (!empty($stuRows)) {
                    $students = array_map(fn($r) => [
                        'id' => (int) $r->id,
                        'firstname' => (string) ($r->firstname ?? ''),
                        'lastname' => (string) ($r->lastname ?? ''),
                    ], $stuRows);
                }
            } catch (\Throwable $e) {
                // ignore
            }

            if (empty($students)) {
                $allStudents = $this->student
                    ->select('id', 'firstname', 'lastname')
                    ->orderBy('lastname', 'ASC')
                    ->findAll();
                $students = array_map(fn($s) => [
                    'id' => (int) ($s['id'] ?? 0),
                    'firstname' => (string) ($s['firstname'] ?? ''),
                    'lastname' => (string) ($s['lastname'] ?? ''),
                ], $allStudents);
            }

            // Class sections for selected year (fallback to all)
            $classSections = $this->classSection
                ->select('id', 'class_section_id', 'class_section_name', 'school_year')
                ->where('school_year', $year)
                ->orderBy('class_section_name', 'ASC')
                ->findAll();

            if (empty($classSections)) {
                $classSections = $this->classSection
                    ->select('id', 'class_section_id', 'class_section_name', 'school_year')
                    ->orderBy('class_section_name', 'ASC')
                    ->findAll();
            }

            $classSectionsFormatted = array_map(static fn($r) => [
                'id' => (int) ($r['id'] ?? 0),
                'class_section_id' => (int) ($r['class_section_id'] ?? ($r['id'] ?? 0)),
                'class_section_name' => (string) ($r['class_section_name'] ?? 'Section'),
                'school_year' => (string) ($r['school_year'] ?? ''),
            ], $classSections);

            return $this->success([
                'ok' => true,
                'schoolYears' => $schoolYears,
                'selectedYear' => $year,
                'semesters' => $semesters,
                'selectedSemester' => $sem,
                'students' => $students,
                'classSections' => $classSectionsFormatted,
                'csrf_token' => csrf_token(),
                'csrf_hash' => csrf_hash(),
            ], 'Report card metadata retrieved successfully');
        } catch (\Throwable $e) {
            Log::error('Report card meta error: ' . $e->getMessage());
            return $this->respondError('Failed to retrieve report card metadata', Response::HTTP_INTERNAL_SERVER_ERROR);
        }
    }

    /**
     * GET /api/v1/printables/badge-status
     * Get badge print status for given users
     */
    public function badgePrintStatus(): JsonResponse
    {
        $ids = $this->request->getGet('user_ids');
        if (is_string($ids)) {
            $ids = array_filter(array_map('trim', explode(',', $ids)), 'strlen');
        }
        if (!is_array($ids)) {
            $ids = $ids ? [$ids] : [];
        }
        $ids = array_values(array_unique(array_map(static fn($v) => (int) $v, $ids)));

        $schoolYear = $this->request->getGet('school_year') ?? $this->schoolYear;

        try {
            $status = $this->badgePrintLog->getStatus($ids, is_string($schoolYear) ? $schoolYear : null);
        } catch (\Throwable $e) {
            Log::error('Badge print status error: ' . $e->getMessage());
            return $this->error('Failed to query status', Response::HTTP_INTERNAL_SERVER_ERROR);
        }

        return $this->success([
            'ok' => true,
            'data' => $status,
            'csrf_token' => csrf_token(),
            'csrf_hash' => csrf_hash(),
        ], 'Badge print status retrieved successfully');
    }

    /**
     * POST /api/v1/printables/badge-status
     * Log a set of badge prints explicitly
     */
    public function logBadgePrint(): JsonResponse
    {
        $data = $this->payloadData();
        if (empty($data)) {
            return $this->error('Invalid request data', Response::HTTP_BAD_REQUEST);
        }

        $ids = $data['user_ids'] ?? [];
        if (!is_array($ids)) {
            $ids = $ids ? [$ids] : [];
        }
        $ids = array_values(array_unique(array_map(static fn($v) => (int) $v, $ids)));

        $roles = $data['roles'] ?? [];
        $class = $data['classes'] ?? [];
        if (!is_array($roles)) {
            $roles = [];
        }
        if (!is_array($class)) {
            $class = [];
        }

        $schoolYear = $data['school_year'] ?? $this->schoolYear;
        $actorId = $this->getCurrentUserId();

        try {
            $cnt = $this->badgePrintLog->logPrints(
                $ids,
                $actorId,
                is_string($schoolYear) ? $schoolYear : null,
                $roles,
                $class,
                1
            );

            return $this->success([
                'ok' => true,
                'inserted' => $cnt,
                'csrf_token' => csrf_token(),
                'csrf_hash' => csrf_hash(),
            ], 'Badge prints logged successfully', Response::HTTP_CREATED);
        } catch (\Throwable $e) {
            Log::error('Log badge print error: ' . $e->getMessage());
            return $this->error('Failed to log badge prints: ' . $e->getMessage(), Response::HTTP_INTERNAL_SERVER_ERROR);
        }
    }

    /**
     * GET /api/v1/printables/students-by-class/{classSectionId}
     * Get students by class section
     */
    public function getByClass($classSectionId): JsonResponse
    {
        try {
            $students = DB::table('student_class sc')
                ->select('s.id', 's.firstname', 's.lastname', 's.registration_grade', 's.gender')
                ->join('students s', 's.id', '=', 'sc.student_id')
                ->where('sc.class_section_id', (int) $classSectionId)
                ->where('sc.school_year', $this->schoolYear)
                ->orderBy('s.lastname', 'asc')
                ->get()
                ->toArray();

            return $this->success($students, 'Students retrieved successfully');
        } catch (\Throwable $e) {
            Log::error('Get students by class error: ' . $e->getMessage());
            return $this->respondError('Failed to retrieve students', Response::HTTP_INTERNAL_SERVER_ERROR);
        }
    }

    /**
     * GET /api/v1/printables/students-by-class/{classSectionId}
     * Alternative endpoint name for students by class
     */
    public function studentsByClass($classSectionId): JsonResponse
    {
        try {
            $rows = $this->student
                ->select('students.id', 'students.firstname', 'students.lastname', 'students.gender', 'cs.class_section_name AS registration_grade')
                ->join('student_class sc', 'sc.student_id', '=', 'students.id', 'inner')
                ->join('classSection cs', 'cs.class_section_id', '=', 'sc.class_section_id', 'inner')
                ->where('sc.school_year', $this->schoolYear)
                ->where('sc.class_section_id', (int) $classSectionId)
                ->groupBy('students.id', 'students.firstname', 'students.lastname', 'students.gender', 'cs.class_section_name')
                ->orderBy('students.firstname', 'ASC')
                ->orderBy('students.lastname', 'ASC')
                ->findAll(1000);

            return $this->success($rows, 'Students retrieved successfully');
        } catch (\Throwable $e) {
            Log::error('Students by class error: ' . $e->getMessage());
            return $this->respondError('Failed to retrieve students', Response::HTTP_INTERNAL_SERVER_ERROR);
        }
    }

    /**
     * GET /api/v1/printables/preview-sticker-counts
     * Preview sticker counts per student
     */
    public function previewStickerCounts(): JsonResponse
    {
        try {
            $classId = (int) ($this->request->getGet('class_id') ?? 0);

            if ($classId > 0) {
                $result = $this->getStickerCountsPerStudentForClass($this->schoolYear, $classId, $this->semester);
            } else {
                $result = $this->getStickerCountsPerStudent($this->schoolYear, $this->semester);
            }

            return $this->success([
                'status' => 'ok',
                'data' => $result,
            ], 'Sticker counts retrieved successfully');
        } catch (\Throwable $e) {
            Log::error('Preview sticker counts error: ' . $e->getMessage());
            return $this->respondError('Failed to retrieve sticker counts', Response::HTTP_INTERNAL_SERVER_ERROR);
        }
    }

    /**
     * Compute sticker counts per student for entire school year
     */
    protected function getStickerCountsPerStudent(string $schoolYear, ?string $semester = null): array
    {
        $specialMap = [
            'KG' => 1,
            '1-A' => 3,
            '1-B' => 4,
            '2-A' => 5,
            '2-B' => 5,
            '9' => 2,
        ];

        $isUpperBlock = static function (string $g): bool {
            return (bool) preg_match('/^(3|4|5|6|7|8)(-[AB])?$/', trim($g));
        };

        $isGrade5 = static function (string $g): bool {
            return (bool) preg_match('/^5(\-|$)/', trim($g));
        };

        $builder = DB::table('student_class sc')
            ->select([
                'sc.student_id',
                's.firstname',
                's.lastname',
                's.is_new',
                'cs.class_section_name AS grade_label',
            ])
            ->join('students s', 's.id', '=', 'sc.student_id')
            ->join('classSection cs', 'cs.class_section_id', '=', 'sc.class_section_id')
            ->join('classes c', 'c.id', '=', 'cs.class_id')
            ->where('sc.school_year', $schoolYear);

        if ($semester !== null && $semester !== '') {
            $builder->where('sc.semester', $semester);
        }

        $rows = $builder->get()->toArray();

        // Filter out Youth and empty labels
        $rows = array_values(array_filter($rows, static function ($r) {
            $g = trim((string) ($r->grade_label ?? ''));
            return $g !== '' && strcasecmp($g, 'youth') !== 0 && strncasecmp($g, 'youth-', 6) !== 0;
        }));

        $out = [];
        $totalPrimary = 0;
        $totalSecondary = 0;

        foreach ($rows as $r) {
            $first = trim((string) ($r->firstname ?? ''));
            $last = trim((string) ($r->lastname ?? ''));
            $grade = trim((string) ($r->grade_label ?? ''));
            $isNew = ((int) ($r->is_new ?? 0)) === 1;

            $primary = 0;
            $secondary = 0;

            if (array_key_exists($grade, $specialMap)) {
                $primary = (int) $specialMap[$grade];
                $secondary = 0;
            } elseif ($isUpperBlock($grade)) {
                if ($isNew) {
                    $primary = 4;
                    $secondary = 0;
                } else {
                    $primary = $isGrade5($grade) ? 3 : 2;
                    $secondary = max(0, 4 - $primary);
                }
            } else {
                $primary = 4;
                $secondary = 0;
            }

            $totalPrimary += $primary;
            $totalSecondary += $secondary;

            $out[] = [
                'student_id' => (int) $r->student_id,
                'firstname' => $first,
                'lastname' => $last,
                'grade_label' => $grade,
                'primary_count' => $primary,
                'secondary_count' => $secondary,
            ];
        }

        return [
            'students' => $out,
            'totals' => [
                'primary' => $totalPrimary,
                'secondary' => $totalSecondary,
                'students' => count($out),
            ],
        ];
    }

    /**
     * Compute sticker counts per student for one class section
     */
    protected function getStickerCountsPerStudentForClass(
        string $schoolYear,
        int $classSectionId,
        ?string $semester = null
    ): array {
        $specialMap = [
            '1-A' => 3,
            '1-B' => 4,
            '2-A' => 5,
            '2-B' => 5,
            '9' => 2,
        ];

        $isUpperBlock = static fn($g) => (bool) preg_match('/^(3|4|5|6|7|8)(-[AB])?$/', trim($g));
        $isGrade5 = static fn($g) => (bool) preg_match('/^5(\-|$)/', trim($g));

        $b = DB::table('student_class sc')
            ->select('sc.student_id', 's.firstname', 's.lastname', 's.is_new', 'cs.class_section_name AS grade_label')
            ->join('students s', 's.id', '=', 'sc.student_id')
            ->join('classSection cs', 'cs.class_section_id', '=', 'sc.class_section_id')
            ->join('classes c', 'c.id', '=', 'cs.class_id')
            ->where('sc.school_year', $schoolYear)
            ->where('sc.class_section_id', $classSectionId);

        if (!empty($semester)) {
            $b->where('sc.semester', $semester);
        }

        $rows = $b->get()->toArray();

        $rows = array_values(array_filter($rows, static function ($r) {
            $g = trim((string) ($r->grade_label ?? ''));
            return $g !== '' && strcasecmp($g, 'youth') !== 0 && strncasecmp($g, 'youth-', 6) !== 0;
        }));

        $out = [];
        $tp = 0;
        $ts = 0;

        foreach ($rows as $r) {
            $g = trim((string) ($r->grade_label ?? ''));
            $isNew = ((int) ($r->is_new ?? 0)) === 1;

            $p = 0;
            $s = 0;

            if (isset($specialMap[$g])) {
                $p = $specialMap[$g];
            } elseif ($isUpperBlock($g)) {
                if ($isNew) {
                    $p = 4;
                } else {
                    $p = $isGrade5($g) ? 3 : 2;
                    $s = max(0, 4 - $p);
                }
            } else {
                $p = 4;
            }

            $tp += $p;
            $ts += $s;

            $out[] = [
                'student_id' => (int) $r->student_id,
                'firstname' => trim((string) ($r->firstname ?? '')),
                'lastname' => trim((string) ($r->lastname ?? '')),
                'grade_label' => $g,
                'primary_count' => $p,
                'secondary_count' => $s,
            ];
        }

        return [
            'students' => $out,
            'totals' => [
                'primary' => $tp,
                'secondary' => $ts,
                'students' => count($out),
            ],
        ];
    }

    /**
     * POST /api/v1/printables/badge
     * Generate staff badge PDF
     * 
     * Note: This method requires FPDF library. The PDF generation logic from the
     * CodeIgniter version should be integrated here when FPDF is available.
     */
    public function badge(): Response
    {
        // TODO: Implement PDF badge generation using FPDF
        // This requires the FPDF library to be installed and the drawBadgeInCell method
        // to be implemented. For now, return an error indicating it's not implemented.
        
        return $this->respondError(
            'Badge PDF generation is not yet implemented. FPDF library integration required.',
            Response::HTTP_NOT_IMPLEMENTED
        );
    }

    /**
     * POST /api/v1/printables/generate-stickers
     * Generate student name stickers PDF
     * 
     * Note: This method requires FPDF library. The PDF generation logic from the
     * CodeIgniter version should be integrated here when FPDF is available.
     */
    public function generateStickers(): Response
    {
        // TODO: Implement PDF sticker generation using FPDF
        // This requires the FPDF library to be installed.
        // For now, return an error indicating it's not implemented.
        
        return $this->respondError(
            'Sticker PDF generation is not yet implemented. FPDF library integration required.',
            Response::HTTP_NOT_IMPLEMENTED
        );
    }

    /**
     * GET /api/v1/printables/report-card/{studentId}
     * Generate single student report card PDF
     * 
     * Note: This method requires FPDF library. The PDF generation logic from the
     * CodeIgniter version should be integrated here when FPDF is available.
     */
    public function generateSingleReport($studentId): Response
    {
        // TODO: Implement PDF report card generation using FPDF
        // This requires the FPDF library to be installed and the formatReportPDF
        // and prepareStudentReportData methods to be implemented.
        
        return $this->respondError(
            'Report card PDF generation is not yet implemented. FPDF library integration required.',
            Response::HTTP_NOT_IMPLEMENTED
        );
    }

    /**
     * GET /api/v1/printables/report-card/class/{classSectionId}
     * Generate class report cards PDF
     * 
     * Note: This method requires FPDF library. The PDF generation logic from the
     * CodeIgniter version should be integrated here when FPDF is available.
     */
    public function generateClassReport($classSectionId): Response
    {
        // TODO: Implement PDF class report cards generation using FPDF
        // This requires the FPDF library to be installed.
        
        return $this->respondError(
            'Class report cards PDF generation is not yet implemented. FPDF library integration required.',
            Response::HTTP_NOT_IMPLEMENTED
        );
    }
}