// API Response structure for user list
export interface AdminUserResponse {
    id: number;
    username: string;
    email: string;
    created_at: string;
    updated_at: string;
    role: {
        code: string;
        name: {
            en: string;
            th: string;
        };
    };
    profile: {
        prefix: {
            en: string;
            th: string;
        };
        first_name: string;
        last_name: string;
        avatar_url: string | null;
        birth_date: string | null;
        phone: string | null;
    };
}

export interface UsersListResponse {
    code: number;
    message: string;
    data: AdminUserResponse[];
}

// Pending Course interfaces
export interface PendingCourseUser {
    id: number;
    email: string;
    username: string;
}

export interface PendingCourseInstructor {
    user_id: number;
    is_primary: boolean;
    user: PendingCourseUser;
}

export interface PendingCourseSubmission {
    id: number;
    submitted_by: number;
    created_at: string;
    submitter: PendingCourseUser;
}

export interface PendingCourse {
    id: number;
    title: {
        th: string;
        en: string;
    };
    slug: string;
    description: {
        th: string;
        en: string;
    };
    thumbnail_url: string | null;
    status: string;
    created_at: string;
    updated_at: string;
    created_by: number;
    creator: PendingCourseUser;
    instructors: PendingCourseInstructor[];
    chapters_count: number;
    lessons_count: number;
    latest_submission: PendingCourseSubmission | null;
}

export interface PendingCoursesListResponse {
    code: number;
    message: string;
    data: PendingCourse[];
    total: number;
}

// Course Detail interfaces for admin review
export interface CourseCategory {
    id: number;
    name: {
        th: string;
        en: string;
    };
}

export interface CourseLesson {
    id: number;
    title: {
        th: string;
        en: string;
    };
    type: string;
    sort_order: number;
    is_published: boolean;
}

export interface CourseChapter {
    id: number;
    title: {
        th: string;
        en: string;
    };
    sort_order: number;
    is_published: boolean;
    lessons: CourseLesson[];
}

export interface ApprovalHistory {
    id: number;
    action: string;
    comment: string | null;
    created_at: string;
    submitter: PendingCourseUser;
    reviewer: PendingCourseUser | null;
}

export interface CourseDetailForReview {
    id: number;
    title: {
        th: string;
        en: string;
    };
    slug: string;
    description: {
        th: string;
        en: string;
    };
    thumbnail_url: string | null;
    price: number;
    is_free: boolean;
    have_certificate: boolean;
    status: string;
    created_at: string;
    updated_at: string;
    category: CourseCategory;
    creator: PendingCourseUser;
    instructors: PendingCourseInstructor[];
    chapters: CourseChapter[];
    approval_history: ApprovalHistory[];
}

export interface CourseDetailForReviewResponse {
    code: number;
    message: string;
    data: CourseDetailForReview;
}

// Mock data for development
const MOCK_USERS: AdminUserResponse[] = [
    {
        id: 1,
        username: 'admin',
        email: 'admin@elearning.local',
        created_at: '2024-01-01T00:00:00Z',
        updated_at: '2024-01-01T00:00:00Z',
        role: { code: 'ADMIN', name: { en: 'Administrator', th: 'ผู้ดูแลระบบ' } },
        profile: {
            prefix: { en: 'Mr.', th: 'นาย' },
            first_name: 'Admin',
            last_name: 'User',
            avatar_url: null,
            birth_date: null,
            phone: '0812345678'
        }
    },
    {
        id: 2,
        username: 'instructor',
        email: 'instructor@elearning.local',
        created_at: '2024-01-01T00:00:00Z',
        updated_at: '2024-01-01T00:00:00Z',
        role: { code: 'INSTRUCTOR', name: { en: 'Instructor', th: 'ผู้สอน' } },
        profile: {
            prefix: { en: 'Mr.', th: 'นาย' },
            first_name: 'John',
            last_name: 'Instructor',
            avatar_url: null,
            birth_date: null,
            phone: '0812345679'
        }
    },
    {
        id: 3,
        username: 'student',
        email: 'student@elearning.local',
        created_at: '2024-01-01T00:00:00Z',
        updated_at: '2024-01-01T00:00:00Z',
        role: { code: 'STUDENT', name: { en: 'Student', th: 'นักเรียน' } },
        profile: {
            prefix: { en: 'Ms.', th: 'นางสาว' },
            first_name: 'Jane',
            last_name: 'Student',
            avatar_url: null,
            birth_date: null,
            phone: '0812345680'
        }
    }
];

// Mock pending courses data
const MOCK_PENDING_COURSES: PendingCourse[] = [
    {
        id: 1,
        title: { th: 'พื้นฐาน JavaScript', en: 'JavaScript Fundamentals' },
        slug: 'javascript-fundamentals',
        description: { th: 'เรียนรู้ JavaScript ตั้งแต่เริ่มต้น', en: 'Learn JavaScript from scratch' },
        thumbnail_url: null,
        status: 'PENDING',
        created_at: '2024-02-01T00:00:00Z',
        updated_at: '2024-02-10T00:00:00Z',
        created_by: 2,
        creator: { id: 2, email: 'instructor@elearning.local', username: 'instructor' },
        instructors: [
            {
                user_id: 2,
                is_primary: true,
                user: { id: 2, email: 'instructor@elearning.local', username: 'instructor' }
            }
        ],
        chapters_count: 5,
        lessons_count: 15,
        latest_submission: {
            id: 1,
            submitted_by: 2,
            created_at: '2024-02-10T00:00:00Z',
            submitter: { id: 2, email: 'instructor@elearning.local', username: 'instructor' }
        }
    },
    {
        id: 2,
        title: { th: 'React สำหรับผู้เริ่มต้น', en: 'React for Beginners' },
        slug: 'react-for-beginners',
        description: { th: 'เรียนรู้ React ตั้งแต่พื้นฐาน', en: 'Learn React from basics' },
        thumbnail_url: null,
        status: 'PENDING',
        created_at: '2024-02-05T00:00:00Z',
        updated_at: '2024-02-12T00:00:00Z',
        created_by: 2,
        creator: { id: 2, email: 'instructor@elearning.local', username: 'instructor' },
        instructors: [
            {
                user_id: 2,
                is_primary: true,
                user: { id: 2, email: 'instructor@elearning.local', username: 'instructor' }
            }
        ],
        chapters_count: 8,
        lessons_count: 24,
        latest_submission: {
            id: 2,
            submitted_by: 2,
            created_at: '2024-02-12T00:00:00Z',
            submitter: { id: 2, email: 'instructor@elearning.local', username: 'instructor' }
        }
    }
];

// Mock course detail for review
const MOCK_COURSE_DETAIL: CourseDetailForReview = {
    id: 1,
    title: { th: 'พื้นฐาน JavaScript', en: 'JavaScript Fundamentals' },
    slug: 'javascript-fundamentals',
    description: { th: 'เรียนรู้ JavaScript ตั้งแต่เริ่มต้น รวมถึง ES6+ features และ best practices', en: 'Learn JavaScript from scratch including ES6+ features and best practices' },
    thumbnail_url: null,
    price: 990,
    is_free: false,
    have_certificate: true,
    status: 'PENDING',
    created_at: '2024-02-01T00:00:00Z',
    updated_at: '2024-02-10T00:00:00Z',
    category: { id: 1, name: { th: 'การพัฒนาเว็บไซต์', en: 'Web Development' } },
    creator: { id: 2, email: 'instructor@elearning.local', username: 'instructor' },
    instructors: [
        {
            user_id: 2,
            is_primary: true,
            user: { id: 2, email: 'instructor@elearning.local', username: 'instructor' }
        }
    ],
    chapters: [
        {
            id: 1,
            title: { th: 'แนะนำ JavaScript', en: 'Introduction to JavaScript' },
            sort_order: 1,
            is_published: true,
            lessons: [
                { id: 1, title: { th: 'JavaScript คืออะไร', en: 'What is JavaScript' }, type: 'VIDEO', sort_order: 1, is_published: true },
                { id: 2, title: { th: 'ติดตั้ง Development Environment', en: 'Setup Development Environment' }, type: 'VIDEO', sort_order: 2, is_published: true },
                { id: 3, title: { th: 'แบบทดสอบบทที่ 1', en: 'Chapter 1 Quiz' }, type: 'QUIZ', sort_order: 3, is_published: true }
            ]
        },
        {
            id: 2,
            title: { th: 'Variables และ Data Types', en: 'Variables and Data Types' },
            sort_order: 2,
            is_published: true,
            lessons: [
                { id: 4, title: { th: 'var, let และ const', en: 'var, let and const' }, type: 'VIDEO', sort_order: 1, is_published: true },
                { id: 5, title: { th: 'Primitive Data Types', en: 'Primitive Data Types' }, type: 'VIDEO', sort_order: 2, is_published: true }
            ]
        }
    ],
    approval_history: [
        {
            id: 1,
            action: 'SUBMITTED',
            comment: null,
            created_at: '2024-02-10T10:00:00Z',
            submitter: { id: 2, email: 'instructor@elearning.local', username: 'instructor' },
            reviewer: null
        }
    ]
};

// Helper function to get auth token from cookie or localStorage
const getAuthToken = (): string => {
    const tokenCookie = useCookie('token');
    return tokenCookie.value || '';
};

export const adminService = {
    async getUsers(): Promise<AdminUserResponse[]> {
        const config = useRuntimeConfig();
        const useMockData = config.public.useMockData as boolean;

        if (useMockData) {
            await new Promise(resolve => setTimeout(resolve, 500));
            return MOCK_USERS;
        }

        const token = getAuthToken();
        const response = await $fetch<UsersListResponse>('/api/admin/usermanagement/users', {
            baseURL: config.public.apiBaseUrl as string,
            headers: {
                Authorization: `Bearer ${token}`
            }
        });

        return response.data;
    },

    async getUserById(id: number): Promise<AdminUserResponse> {
        const config = useRuntimeConfig();
        const useMockData = config.public.useMockData as boolean;

        if (useMockData) {
            await new Promise(resolve => setTimeout(resolve, 300));
            const user = MOCK_USERS.find(u => u.id === id);
            if (!user) throw new Error('User not found');
            return user;
        }

        const token = getAuthToken();
        const response = await $fetch<AdminUserResponse>(`/api/admin/usermanagement/users/${id}`, {
            baseURL: config.public.apiBaseUrl as string,
            headers: {
                Authorization: `Bearer ${token}`
            }
        });

        return response;
    },

    async updateUserRole(userId: number, roleId: number): Promise<void> {
        const config = useRuntimeConfig();
        const useMockData = config.public.useMockData as boolean;

        if (useMockData) {
            await new Promise(resolve => setTimeout(resolve, 500));
            return;
        }

        const token = getAuthToken();
        await $fetch(`/api/admin/usermanagement/role/${userId}`, {
            method: 'PUT',
            baseURL: config.public.apiBaseUrl as string,
            headers: {
                Authorization: `Bearer ${token}`
            },
            body: {
                id: userId,
                role_id: roleId
            }
        });
    },

    async deleteUser(userId: number): Promise<void> {
        const config = useRuntimeConfig();
        const useMockData = config.public.useMockData as boolean;

        if (useMockData) {
            await new Promise(resolve => setTimeout(resolve, 500));
            return;
        }

        const token = getAuthToken();
        await $fetch(`/api/admin/usermanagement/users/${userId}`, {
            method: 'DELETE',
            baseURL: config.public.apiBaseUrl as string,
            headers: {
                Authorization: `Bearer ${token}`
            }
        });
    },

    // ============ Pending Courses ============
    async getPendingCourses(): Promise<PendingCourse[]> {
        const config = useRuntimeConfig();
        const useMockData = config.public.useMockData as boolean;

        if (useMockData) {
            await new Promise(resolve => setTimeout(resolve, 500));
            return MOCK_PENDING_COURSES;
        }

        const token = getAuthToken();
        const response = await $fetch<PendingCoursesListResponse>('/api/admin/courses/pending', {
            baseURL: config.public.apiBaseUrl as string,
            headers: {
                Authorization: `Bearer ${token}`
            }
        });

        return response.data;
    },

    async getCourseForReview(courseId: number): Promise<CourseDetailForReview> {
        const config = useRuntimeConfig();
        const useMockData = config.public.useMockData as boolean;

        if (useMockData) {
            await new Promise(resolve => setTimeout(resolve, 500));
            return MOCK_COURSE_DETAIL;
        }

        const token = getAuthToken();
        const response = await $fetch<CourseDetailForReviewResponse>(`/api/admin/courses/${courseId}`, {
            baseURL: config.public.apiBaseUrl as string,
            headers: {
                Authorization: `Bearer ${token}`
            }
        });

        return response.data;
    },

    async approveCourse(courseId: number, comment?: string): Promise<void> {
        const config = useRuntimeConfig();
        const useMockData = config.public.useMockData as boolean;

        if (useMockData) {
            await new Promise(resolve => setTimeout(resolve, 500));
            return;
        }

        const token = getAuthToken();
        await $fetch(`/api/admin/courses/${courseId}/approve`, {
            method: 'POST',
            baseURL: config.public.apiBaseUrl as string,
            headers: {
                Authorization: `Bearer ${token}`
            },
            body: { comment: comment || '' }
        });
    },

    async rejectCourse(courseId: number, comment: string): Promise<void> {
        const config = useRuntimeConfig();
        const useMockData = config.public.useMockData as boolean;

        if (useMockData) {
            await new Promise(resolve => setTimeout(resolve, 500));
            return;
        }

        const token = getAuthToken();
        await $fetch(`/api/admin/courses/${courseId}/reject`, {
            method: 'POST',
            baseURL: config.public.apiBaseUrl as string,
            headers: {
                Authorization: `Bearer ${token}`
            },
            body: { comment }
        });
    },

    // ============ Categories ============
    async getCategories(): Promise<CategoryResponse[]> {
        const config = useRuntimeConfig();
        const useMockData = config.public.useMockData as boolean;

        if (useMockData) {
            await new Promise(resolve => setTimeout(resolve, 500));
            return MOCK_CATEGORIES;
        }

        const token = getAuthToken();
        const response = await $fetch<CategoriesListResponse>('/api/categories', {
            baseURL: config.public.apiBaseUrl as string,
            headers: {
                Authorization: `Bearer ${token}`
            }
        });

        return response.data.categories;
    },

    async createCategory(data: CreateCategoryRequest): Promise<CategoryResponse> {
        const config = useRuntimeConfig();
        const useMockData = config.public.useMockData as boolean;

        if (useMockData) {
            await new Promise(resolve => setTimeout(resolve, 500));
            return { ...MOCK_CATEGORIES[0], id: Date.now() };
        }

        const token = getAuthToken();
        const response = await $fetch<CategoryResponse>('/api/admin/categories', {
            method: 'POST',
            baseURL: config.public.apiBaseUrl as string,
            headers: {
                Authorization: `Bearer ${token}`
            },
            body: data
        });

        return response;
    },

    async updateCategory(id: number, data: UpdateCategoryRequest): Promise<CategoryResponse> {
        const config = useRuntimeConfig();
        const useMockData = config.public.useMockData as boolean;

        if (useMockData) {
            await new Promise(resolve => setTimeout(resolve, 500));
            return { ...MOCK_CATEGORIES[0], id };
        }

        const token = getAuthToken();
        const response = await $fetch<CategoryResponse>(`/api/admin/categories/${id}`, {
            method: 'PUT',
            baseURL: config.public.apiBaseUrl as string,
            headers: {
                Authorization: `Bearer ${token}`
            },
            body: data
        });

        return response;
    },

    async deleteCategory(id: number): Promise<void> {
        const config = useRuntimeConfig();
        const useMockData = config.public.useMockData as boolean;

        if (useMockData) {
            await new Promise(resolve => setTimeout(resolve, 500));
            return;
        }

        const token = getAuthToken();
        await $fetch(`/api/admin/categories/${id}`, {
            method: 'DELETE',
            baseURL: config.public.apiBaseUrl as string,
            headers: {
                Authorization: `Bearer ${token}`
            }
        });
    }
};

// Category interfaces
export interface CategoryResponse {
    id: number;
    name: {
        en: string;
        th: string;
    };
    slug: string;
    description: {
        en: string;
        th: string;
    };
    icon: string;
    sort_order: number;
    is_active: boolean;
    created_at: string;
    created_by: number;
    updated_at: string;
    updated_by: number | null;
}

export interface CategoriesListResponse {
    code: number;
    message: string;
    data: {
        categories: CategoryResponse[];
    };
}

export interface CreateCategoryRequest {
    name: {
        en: string;
        th: string;
    };
    slug: string;
    description: {
        en: string;
        th: string;
    };
    created_by?: number;
}

export interface UpdateCategoryRequest {
    id: number;
    name: {
        en: string;
        th: string;
    };
    slug: string;
    description: {
        en: string;
        th: string;
    };
}

// Mock categories
const MOCK_CATEGORIES: CategoryResponse[] = [
    {
        id: 1,
        name: { en: 'Web Development', th: 'การพัฒนาเว็บไซต์' },
        slug: 'web-development',
        description: { en: 'Learn web development', th: 'หลักสูตรเกี่ยวกับการพัฒนาเว็บไซต์และเว็บแอปพลิเคชัน' },
        icon: 'code',
        sort_order: 1,
        is_active: true,
        created_at: '2024-01-15T00:00:00Z',
        created_by: 1,
        updated_at: '2024-01-15T00:00:00Z',
        updated_by: null
    },
    {
        id: 2,
        name: { en: 'Mobile Development', th: 'การพัฒนาแอปพลิเคชันมือถือ' },
        slug: 'mobile-development',
        description: { en: 'Learn mobile app development', th: 'หลักสูตรเกี่ยวกับการพัฒนาแอปพลิเคชันบนมือถือ' },
        icon: 'smartphone',
        sort_order: 2,
        is_active: true,
        created_at: '2024-01-20T00:00:00Z',
        created_by: 1,
        updated_at: '2024-01-20T00:00:00Z',
        updated_by: null
    },
    {
        id: 3,
        name: { en: 'Database', th: 'ฐานข้อมูล' },
        slug: 'database',
        description: { en: 'Learn database management', th: 'หลักสูตรเกี่ยวกับการออกแบบและจัดการฐานข้อมูล' },
        icon: 'storage',
        sort_order: 3,
        is_active: true,
        created_at: '2024-02-01T00:00:00Z',
        created_by: 1,
        updated_at: '2024-02-01T00:00:00Z',
        updated_by: null
    }
];