<?php

namespace App\Livewire;

use App\Models\Student;
use App\Models\Teacher;
use Livewire\Component;

class TeacherStudentSelector extends Component
{
    public ?string $teacherId = null;
    public ?string $studentId = null;
    public bool $required = false;
    public string $teacherLabel = '选择老师';
    public string $studentLabel = '选择学生';
    public string $teacherPlaceholder = '请选择老师...';
    public string $studentPlaceholder = '请选择学生...';
    public ?string $teacherHelperText = null;
    public ?string $studentHelperText = null;

    public array $teacherOptions = [];
    public array $studentOptions = [];

    protected $listeners = ['refreshTeacherStudentSelector' => '$refresh'];

    public function mount(
        ?string $initialTeacherId = null,
        ?string $initialStudentId = null,
        bool $required = false,
        string $teacherLabel = '选择老师',
        string $studentLabel = '选择学生',
        string $teacherPlaceholder = '请选择老师...',
        string $studentPlaceholder = '请选择学生...',
        ?string $teacherHelperText = null,
        ?string $studentHelperText = null
    ): void {
        $this->teacherId = $initialTeacherId;
        $this->studentId = $initialStudentId;
        $this->required = $required;
        $this->teacherLabel = $teacherLabel;
        $this->studentLabel = $studentLabel;
        $this->teacherPlaceholder = $teacherPlaceholder;
        $this->studentPlaceholder = $studentPlaceholder;
        $this->teacherHelperText = $teacherHelperText;
        $this->studentHelperText = $studentHelperText;

        \Illuminate\Support\Facades\Log::info('TeacherStudentSelector组件已挂载', [
            'initial_teacher_id' => $initialTeacherId,
            'initial_student_id' => $initialStudentId,
            'has_teacher' => !empty($initialTeacherId),
            'has_student' => !empty($initialStudentId)
        ]);

        $this->loadTeacherOptions();
        
        // 验证 teacherId 是否在选项中
        if ($this->teacherId && !array_key_exists($this->teacherId, $this->teacherOptions)) {
            $this->teacherId = null;
        }

        if ($this->teacherId) {
            $this->loadStudentOptions();
        }
    }

    public function updatedTeacherId($value): void
    {
        \Illuminate\Support\Facades\Log::info('教师选择已更新', [
            'old_value' => $this->teacherId,
            'new_value' => $value,
            'is_empty' => empty($value)
        ]);

        // 当教师选择变化时，清空之前选择的学生
        $this->studentId = null;
        $this->loadStudentOptions();

        // 发送事件到父组件
        $this->dispatch('teacherChanged', teacherId: $value);

        // 强制刷新组件视图
        $this->dispatch('$refresh');
    }

    public function updatedStudentId($value): void
    {
        \Illuminate\Support\Facades\Log::info('学生选择已更新', [
            'teacher_id' => $this->teacherId,
            'student_id' => $value,
            'is_empty' => empty($value),
            'previous_value' => $this->studentId
        ]);

        // 发送事件到父组件
        $this->dispatch('studentChanged',
            teacherId: $this->teacherId,
            studentId: $value
        );

        // 同时分发到浏览器窗口，确保父组件能接收到
        $this->dispatch('window-student-changed',
            teacherId: $this->teacherId,
            studentId: $value
        );

        // 强制刷新组件视图
        $this->dispatch('$refresh');

        \Illuminate\Support\Facades\Log::info('学生选择事件已分发', [
            'dispatched' => true
        ]);
    }

    public function loadTeacherOptions(): void
    {
        try {
            $teachers = Teacher::query()
                ->leftJoin('users as u', 'teachers.teacher_id', '=', 'u.user_id')
                ->select(
                    'teachers.teacher_id',
                    'teachers.name',
                    'teachers.subject',
                    'u.username',
                    'u.email'
                )
                ->orderBy('teachers.name')
                ->get();

            // 检查是否有学生没有对应的老师记录
            $teacherIds = $teachers->pluck('teacher_id')->toArray();
            $missingTeacherIds = Student::query()
                ->distinct()
                ->whereNotIn('teacher_id', $teacherIds)
                ->pluck('teacher_id')
                ->toArray();

            $teachersArray = $teachers->all();

            if (!empty($missingTeacherIds)) {
                foreach ($missingTeacherIds as $missingId) {
                    $teachersArray[] = (object) [
                        'teacher_id' => $missingId,
                        'name' => '未知老师 (' . $missingId . ')',
                        'subject' => '未知',
                        'username' => null,
                        'email' => null
                    ];
                }

                usort($teachersArray, function($a, $b) {
                    return strcmp($a->name, $b->name);
                });
            }

            $this->teacherOptions = collect($teachersArray)->mapWithKeys(function ($teacher) {
                // 构建详细的显示文本，包含所有可用字段
                $displayName = trim($teacher->name ?? $teacher->teacher_id);
                $subject = $teacher->subject ? " ({$teacher->subject})" : '';
                $username = $teacher->username ? " [{$teacher->username}]" : '';
                $email = $teacher->email ? " <{$teacher->email}>" : '';

                return [
                    $teacher->teacher_id => "{$displayName}{$subject}{$username}{$email}"
                ];
            })->toArray();

            \Illuminate\Support\Facades\Log::info('已加载教师列表', [
                'teacher_count' => count($this->teacherOptions)
            ]);

        } catch (\Exception $e) {
            \Illuminate\Support\Facades\Log::error('加载老师列表失败', [
                'error' => $e->getMessage()
            ]);
            $this->teacherOptions = [];
        }
    }

    public function loadStudentOptions(): void
    {
        if (empty($this->teacherId)) {
            $this->studentOptions = [];
            return;
        }

        try {
            $students = Student::query()
                ->leftJoin('users as u', 'students.student_id', '=', 'u.user_id')
                ->where('students.teacher_id', $this->teacherId)
                ->select(
                    'students.student_id',
                    'students.name',
                    'students.grade',
                    'students.class_name',
                    'u.username',
                    'u.email',
                    'students.created_at'
                )
                ->orderBy('students.grade')
                ->orderBy('students.class_name')
                ->orderBy('students.name')
                ->get();

            \Illuminate\Support\Facades\Log::info('已加载学生列表', [
                'teacher_id' => $this->teacherId,
                'student_count' => count($students)
            ]);

            // 如果没有找到学生，可能是因为 teacher_id 不在 teachers 表中
            // 但学生表中确实有该 teacher_id 的记录，所以直接返回查询结果
            $this->studentOptions = $students->mapWithKeys(function ($student) {
                // 构建详细的显示文本，包含所有可用字段
                $displayName = trim($student->name ?? $student->student_id);
                $gradeClass = trim("{$student->grade} - {$student->class_name}");
                $username = $student->username ? " [{$student->username}]" : '';
                $email = $student->email ? " <{$student->email}>" : '';

                return [
                    $student->student_id => "{$displayName} ({$gradeClass}){$username}{$email}"
                ];
            })->toArray();

        } catch (\Exception $e) {
            \Illuminate\Support\Facades\Log::error('加载学生列表失败', [
                'teacher_id' => $this->teacherId,
                'error' => $e->getMessage()
            ]);
            $this->studentOptions = [];
        }
    }

    public function getSelectedTeacherName(): string
    {
        return $this->teacherOptions[$this->teacherId] ?? '未选择';
    }

    public function getSelectedStudentName(): string
    {
        return $this->studentOptions[$this->studentId] ?? '未选择';
    }

    public function hasSelections(): bool
    {
        return !empty($this->teacherId) && !empty($this->studentId);
    }

    public function isStudentDropdownDisabled(): bool
    {
        return empty($this->teacherId);
    }

    public function hasStudents(): bool
    {
        return !empty($this->studentOptions);
    }

    /**
     * 获取学生的详细信息（用于父组件）
     */
    public function getStudentDetails(string $studentId): ?array
    {
        if (empty($studentId) || empty($this->teacherId)) {
            return null;
        }

        try {
            $student = Student::query()
                ->leftJoin('users as u', 'students.student_id', '=', 'u.user_id')
                ->where('students.student_id', $studentId)
                ->where('students.teacher_id', $this->teacherId)
                ->select(
                    'students.student_id',
                    'students.name',
                    'students.grade',
                    'students.class_name',
                    'u.username',
                    'u.email'
                )
                ->first();

            if (!$student) {
                return null;
            }

            return [
                'student_id' => $student->student_id,
                'name' => $student->name,
                'grade' => $student->grade,
                'class_name' => $student->class_name,
                'username' => $student->username,
                'email' => $student->email,
                'display_name' => trim($student->name ?? $student->student_id) . " ({$student->grade} - {$student->class_name})",
                'full_display' => trim($student->name ?? $student->student_id) .
                    " ({$student->grade} - {$student->class_name})" .
                    ($student->username ? " [{$student->username}]" : '') .
                    ($student->email ? " <{$student->email}>" : '')
            ];
        } catch (\Exception $e) {
            \Illuminate\Support\Facades\Log::error('获取学生详细信息失败', [
                'student_id' => $studentId,
                'error' => $e->getMessage()
            ]);
            return null;
        }
    }

    /**
     * 获取教师的详细信息（用于父组件）
     */
    public function getTeacherDetails(string $teacherId): ?array
    {
        if (empty($teacherId)) {
            return null;
        }

        try {
            $teacher = Teacher::query()
                ->leftJoin('users as u', 'teachers.teacher_id', '=', 'u.user_id')
                ->where('teachers.teacher_id', $teacherId)
                ->select(
                    'teachers.teacher_id',
                    'teachers.name',
                    'teachers.subject',
                    'u.username',
                    'u.email'
                )
                ->first();

            if (!$teacher) {
                return null;
            }

            return [
                'teacher_id' => $teacher->teacher_id,
                'name' => $teacher->name,
                'subject' => $teacher->subject,
                'username' => $teacher->username,
                'email' => $teacher->email,
                'display_name' => trim($teacher->name ?? $teacher->teacher_id) . ($teacher->subject ? " ({$teacher->subject})" : ''),
                'full_display' => trim($teacher->name ?? $teacher->teacher_id) .
                    ($teacher->subject ? " ({$teacher->subject})" : '') .
                    ($teacher->username ? " [{$teacher->username}]" : '') .
                    ($teacher->email ? " <{$teacher->email}>" : '')
            ];
        } catch (\Exception $e) {
            \Illuminate\Support\Facades\Log::error('获取教师详细信息失败', [
                'teacher_id' => $teacherId,
                'error' => $e->getMessage()
            ]);
            return null;
        }
    }

    public function render()
    {
        return view('livewire.teacher-student-selector');
    }
}