import React, { useState, useEffect } from 'react';
import { Link, Head, usePage } from '@inertiajs/react';
import { 
    ChevronLeft, 
    Menu, 
    Search, 
    CheckCircle, 
    Circle, 
    ChevronDown, 
    ChevronRight,
    PlayCircle,
    FileText,
    HelpCircle
} from 'lucide-react';
import { Button } from '@/Components/ui/button';
import { ScrollArea } from '@/Components/ui/scroll-area';
import { Sheet, SheetContent, SheetTrigger } from '@/Components/ui/sheet';
import { Progress } from '@/Components/ui/progress';
import { cn } from '@/lib/utils';
import { ModeToggle } from '@/Components/ModeToggle';

// Interfaces for Props
interface Lesson {
    id: string;
    title: string;
    slug: string;
    type: 'video' | 'text' | 'quiz' | 'pdf';
    is_completed: boolean;
    duration_seconds: number;
}

interface Module {
    id: string;
    title: string;
    lessons: Lesson[];
}

interface Course {
    id: string;
    title: string;
    slug: string;
    progress_percentage: number;
}

interface CourseLayoutProps {
    children: React.ReactNode;
    course: Course;
    modules: Module[];
    currentLesson?: Lesson;
}

export default function CourseLayout({
    children,
    course,
    modules = [],
    currentLesson
}: CourseLayoutProps) {
    const [isSidebarOpen, setIsSidebarOpen] = useState(true);
    const [openModules, setOpenModules] = useState<string[]>([]);
    const { url } = usePage();

    // Default open all modules or just the active one
    useEffect(() => {
        if (modules.length > 0) {
            // Find module containing current lesson
            const activeModule = modules.find(m => m.lessons.some(l => l.slug === currentLesson?.slug));
            if (activeModule) {
                setOpenModules(prev => [...new Set([...prev, activeModule.id])]);
            } else {
                // If no active lesson (e.g. course home), open first module
                setOpenModules([modules[0].id]);
            }
        }
    }, [modules, currentLesson]);

    const toggleModule = (moduleId: string) => {
        setOpenModules(prev => 
            prev.includes(moduleId) 
                ? prev.filter(id => id !== moduleId) 
                : [...prev, moduleId]
        );
    };

    const getLessonIcon = (type: string) => {
        switch (type) {
            case 'video': return <PlayCircle size={14} />;
            case 'quiz': return <HelpCircle size={14} />;
            case 'pdf': return <FileText size={14} />;
            default: return <FileText size={14} />;
        }
    };

    return (
        <div className="min-h-screen bg-background flex font-sans text-foreground">
            {/* Mobile Sheet Sidebar */}
            <Sheet>
                <div className="lg:hidden fixed top-0 left-0 right-0 h-14 border-b bg-background/95 backdrop-blur z-40 flex items-center px-4 justify-between">
                    <div className="flex items-center gap-3">
                        <SheetTrigger asChild>
                            <Button variant="ghost" size="icon" className="-ml-2">
                                <Menu size={20} />
                            </Button>
                        </SheetTrigger>
                        <span className="font-semibold text-sm truncate max-w-[200px]">{course.title}</span>
                    </div>
                    <Link href={route('dashboard')}>
                        <Button variant="ghost" size="sm" className="text-xs">Keluar</Button>
                    </Link>
                </div>
                
                <SheetContent side="left" className="p-0 w-[85vw] max-w-[320px]">
                   <SidebarContent 
                       course={course} 
                       modules={modules} 
                       currentLesson={currentLesson}
                       openModules={openModules}
                       toggleModule={toggleModule}
                       getLessonIcon={getLessonIcon}
                   />
                </SheetContent>
            </Sheet>

            {/* Desktop Sidebar */}
            <aside 
                className={cn(
                    "hidden lg:flex flex-col w-80 border-r bg-muted/30 fixed inset-y-0 left-0 z-30 transition-all duration-300",
                    !isSidebarOpen && "-ml-80"
                )}
            >
                <SidebarContent 
                    course={course} 
                    modules={modules} 
                    currentLesson={currentLesson}
                    openModules={openModules}
                    toggleModule={toggleModule}
                    getLessonIcon={getLessonIcon}
                />
            </aside>

            {/* Main Content Area */}
            <main 
                className={cn(
                    "flex-1 flex flex-col min-h-screen transition-all duration-300 bg-background",
                    isSidebarOpen ? "lg:ml-80" : "lg:ml-0",
                    "pt-14 lg:pt-0" // Mobile padding
                )}
            >
                {/* Desktop Topbar */}
                <header className="hidden lg:flex h-14 items-center justify-between px-6 border-b bg-background sticky top-0 z-20">
                    <div className="flex items-center gap-4">
                        <Button 
                            variant="ghost" 
                            size="icon" 
                            onClick={() => setIsSidebarOpen(!isSidebarOpen)}
                            className="text-muted-foreground hover:text-foreground"
                            title={isSidebarOpen ? "Close Sidebar" : "Open Sidebar"}
                        >
                            <Menu size={18} />
                        </Button>
                        <nav className="flex items-center text-sm text-muted-foreground">
                            <Link href={route('dashboard')} className="hover:text-foreground transition-colors">
                                Dashboard
                            </Link>
                            <ChevronRight size={14} className="mx-2" />
                            <Link href={route('courses.index')} className="hover:text-foreground transition-colors">
                                Courses
                            </Link>
                            <ChevronRight size={14} className="mx-2" />
                            <span className="font-medium text-foreground truncate max-w-[300px]">
                                {currentLesson?.title || course.title}
                            </span>
                        </nav>
                    </div>
                    <div className="flex items-center gap-3">
                         <div className="flex flex-col items-end mr-2">
                             <div className="flex items-center gap-2 mb-1">
                                <span className="text-[10px] font-bold uppercase tracking-wider text-muted-foreground">Progress</span>
                                <span className="text-xs font-bold">{course.progress_percentage}%</span>
                             </div>
                             <Progress value={course.progress_percentage} className="w-32 h-1.5" />
                         </div>
                         <ModeToggle />
                    </div>
                </header>

                {/* Content Slot */}
                <div className="flex-1 overflow-auto">
                    <div className="max-w-4xl mx-auto p-6 lg:p-10 animate-in fade-in slide-in-from-bottom-4 duration-700">
                        {children}
                    </div>
                </div>
            </main>
        </div>
    );
}

function SidebarContent({ course, modules, currentLesson, openModules, toggleModule, getLessonIcon }: any) {
    return (
        <div className="flex flex-col h-full">
            {/* Header */}
            <div className="p-4 border-b bg-background/50 backdrop-blur-sm">
                <Link 
                    href={route('dashboard')} 
                    className="flex items-center text-xs font-medium text-muted-foreground hover:text-primary mb-4 transition-colors group"
                >
                    <ChevronLeft size={14} className="mr-1 group-hover:-translate-x-1 transition-transform" />
                    Kembali ke Dashboard
                </Link>
                <div className="flex items-center gap-3 mb-2">
                     <div className="h-10 w-10 rounded-lg bg-gradient-to-br from-nihonbuzz-red to-orange-500 flex items-center justify-center text-white font-bold text-sm shrink-0 shadow-lg shadow-orange-500/20">
                        {course.title.charAt(0)}
                    </div>
                    <h2 className="font-bold leading-tight text-sm line-clamp-2">{course.title}</h2>
                </div>
                
                <div className="relative mt-3">
                    <Search className="absolute left-2.5 top-1/2 -translate-y-1/2 h-3.5 w-3.5 text-muted-foreground" />
                    <input 
                        className="w-full h-8 pl-8 pr-3 rounded-md border border-input bg-background/50 text-xs focus:outline-none focus:ring-1 focus:ring-primary transition-all placeholder:text-muted-foreground"
                        placeholder="Cari materi..." 
                    />
                </div>
            </div>

            {/* Curriculum List */}
            <ScrollArea className="flex-1 px-3 py-4">
                <div className="space-y-4">
                    {modules.map((module: any, index: number) => (
                        <div key={module.id} className="space-y-1">
                            <button 
                                onClick={() => toggleModule(module.id)}
                                className="flex items-center w-full text-left gap-2 px-2 py-1.5 text-xs font-bold uppercase tracking-wider text-muted-foreground hover:text-foreground transition-colors group"
                            >
                                <ChevronRight 
                                    size={12} 
                                    className={cn(
                                        "transition-transform bg-muted rounded-sm",
                                        openModules.includes(module.id) && "rotate-90"
                                    )} 
                                />
                                <span className="line-clamp-1 group-hover:underline decoration-border underline-offset-4">{module.title}</span>
                            </button>

                            {openModules.includes(module.id) && (
                                <div className="space-y-0.5 ml-1 pl-2 border-l border-border/40">
                                    {module.lessons.map((lesson: any) => {
                                        const isActive = currentLesson?.slug === lesson.slug;
                                        return (
                                            <Link
                                                key={lesson.id}
                                                href={route('courses.learn', { course: course.slug, lesson: lesson.slug })}
                                                className={cn(
                                                    "flex items-start gap-2.5 px-3 py-2 rounded-md text-sm transition-all duration-200 group relative",
                                                    isActive 
                                                        ? "bg-primary/10 text-primary font-medium" 
                                                        : "text-muted-foreground hover:bg-muted/50 hover:text-foreground"
                                                )}
                                            >
                                                <div className="mt-0.5 shrink-0 transition-colors group-hover:text-foreground">
                                                    {lesson.is_completed ? (
                                                        <CheckCircle size={14} className="text-green-500" />
                                                    ) : (
                                                        <Circle size={14} className={cn("text-muted-foreground/30", isActive && "text-primary/30")} />
                                                    )}
                                                </div>
                                                <div className="space-y-0.5">
                                                    <span className="line-clamp-2 leading-snug">{lesson.title}</span>
                                                    <div className="flex items-center gap-2 text-[10px] text-muted-foreground/50 font-medium">
                                                        <span className="flex items-center gap-1">
                                                            {getLessonIcon(lesson.type)}
                                                            <span className="capitalize">{lesson.type}</span>
                                                        </span>
                                                        {lesson.duration_seconds > 0 && (
                                                           <>
                                                           <span>•</span>
                                                           <span>{Math.ceil(lesson.duration_seconds / 60)} min</span>
                                                           </>
                                                        )}
                                                    </div>
                                                </div>
                                                {isActive && (
                                                    <div className="absolute left-0 top-1/2 -translate-y-1/2 w-0.5 h-full bg-primary rounded-r-full" />
                                                )}
                                            </Link>
                                        );
                                    })}
                                </div>
                            )}
                        </div>
                    ))}
                </div>
            </ScrollArea>
            
            {/* Footer User Info */}
            <div className="p-4 border-t bg-background/50 text-[10px] text-center text-muted-foreground">
                Built for <span className="font-bold text-foreground">Future Japan Enthusisasts</span>
            </div>
        </div>
    );
}