// models/courses/associations.js

const { Course, CourseProductCategory } = require("./courses.mdl");
const Unit = require("./units.mdl");
const Lesson = require("./lessons.mdl");
const LessonPage = require("./lesson_page.mdl");
const CourseObjective = require("./course_objective.mdl");
const LessonObjective = require("./lesson_objective.mdl");
const CoursePrerequisite = require("./course_prerequisite.mdl");
const CourseAssessment = require("./course_assessment.mdl");
const UnitQuiz = require("./unit_quiz.mdl");
const QuizQuestion = require("./quiz_question.mdl");
const QuizOption = require("./quiz_option.mdl");
const mdl_Users = require("../users/users.mdl");
const QuizAttempt = require("./quiz_attempt.mdl");
const AssessmentSession       = require("./assessment_session.mdl");
const mdl_Category            = require("./categories.mdl");
const Certificate             = require("./certificate.mdl");
const CourseInstructor        = require("./course_instructor.mdl");
const CourseReadingProgress   = require("./course_reading_progress.mdl");

// ── CourseReadingProgress ─────────────────────────────────────────────────────
CourseReadingProgress.belongsTo(mdl_Users, { foreignKey: 'user_id',   as: 'user'   });
CourseReadingProgress.belongsTo(Course,    { foreignKey: 'course_id', as: 'course' });
mdl_Users.hasMany(CourseReadingProgress,   { foreignKey: 'user_id',   as: 'courseReadingProgress' });
Course.hasMany(CourseReadingProgress,      { foreignKey: 'course_id', as: 'readingProgress'       });

// ── Course ────────────────────────────────────────────────────────────────────
Course.belongsTo(mdl_Users, { as: "creator", foreignKey: "createdBy" });
Course.belongsTo(mdl_Users, { as: "updater", foreignKey: "updatedBy" });
Course.hasMany(Unit, { as: "units", foreignKey: "course_id" });
Course.hasMany(CourseObjective, { as: "objectives", foreignKey: "course_id" });
Course.hasMany(CoursePrerequisite, { as: "prerequisites", foreignKey: "course_id" });
Course.hasOne(CourseAssessment, { as: "assessment",    foreignKey: "course_id" });
Course.hasMany(Certificate,      { as: "certificates",  foreignKey: "course_id" });
Course.hasMany(CourseInstructor, { as: "instructors",   foreignKey: "course_id" });
CourseInstructor.belongsTo(Course,    { as: "course", foreignKey: "course_id" });
CourseInstructor.belongsTo(mdl_Users, { as: "user",   foreignKey: "user_id"   });
Course.belongsToMany(mdl_Category, { through: CourseProductCategory, foreignKey: 'course_id',   otherKey: 'category_id', as: 'categories' });
mdl_Category.belongsToMany(Course,        { through: CourseProductCategory, foreignKey: 'category_id', otherKey: 'course_id',   as: 'courses'    });

// ── Unit ──────────────────────────────────────────────────────────────────────
Unit.belongsTo(Course, { as: "course", foreignKey: "course_id" });
Unit.belongsTo(mdl_Users, { as: "creator", foreignKey: "createdBy" });
Unit.belongsTo(mdl_Users, { as: "updater", foreignKey: "updatedBy" });
Unit.hasMany(Lesson, { as: "lessons", foreignKey: "unit_id" });
Unit.hasOne(UnitQuiz, { as: "quiz", foreignKey: "unit_id" });

// ── Lesson ────────────────────────────────────────────────────────────────────
Lesson.belongsTo(Unit, { as: "unit", foreignKey: "unit_id" });
Lesson.belongsTo(mdl_Users, { as: "creator", foreignKey: "createdBy" });
Lesson.belongsTo(mdl_Users, { as: "updater", foreignKey: "updatedBy" });
Lesson.hasOne(LessonPage, { as: "page", foreignKey: "lesson_id" });
Lesson.hasMany(LessonObjective, { as: "objectives", foreignKey: "lesson_id" });

// ── UnitQuiz ──────────────────────────────────────────────────────────────────
UnitQuiz.belongsTo(Unit, { as: "unit", foreignKey: "unit_id" });
UnitQuiz.belongsTo(mdl_Users, { as: "creator", foreignKey: "createdBy" });
UnitQuiz.belongsTo(mdl_Users, { as: "updater", foreignKey: "updatedBy" });
UnitQuiz.hasMany(QuizQuestion, { as: "questions", foreignKey: "quiz_id" });

// ── CourseAssessment ──────────────────────────────────────────────────────────
CourseAssessment.belongsTo(Course, { as: "course", foreignKey: "course_id" });
CourseAssessment.belongsTo(mdl_Users, { as: "creator", foreignKey: "createdBy" });
CourseAssessment.belongsTo(mdl_Users, { as: "updater", foreignKey: "updatedBy" });
CourseAssessment.hasMany(QuizQuestion, { as: "questions", foreignKey: "assessment_id" });

// ── QuizQuestion ──────────────────────────────────────────────────────────────
QuizQuestion.belongsTo(UnitQuiz, { as: "quiz", foreignKey: "quiz_id" });
QuizQuestion.belongsTo(CourseAssessment, { as: "assessment", foreignKey: "assessment_id" });
QuizQuestion.hasMany(QuizOption, { as: "options", foreignKey: "question_id" });

// ── QuizOption ────────────────────────────────────────────────────────────────
QuizOption.belongsTo(QuizQuestion, { as: "question", foreignKey: "question_id" });

// ── QuizAttempt ───────────────────────────────────────────────────────────────
QuizAttempt.belongsTo(UnitQuiz, { as: "quiz", foreignKey: "quiz_id" });
QuizAttempt.belongsTo(CourseAssessment, { as: "assessment", foreignKey: "assessment_id" });
QuizAttempt.belongsTo(mdl_Users, { as: "user", foreignKey: "user_id" });
UnitQuiz.hasMany(QuizAttempt, { as: "attempts", foreignKey: "quiz_id" });
CourseAssessment.hasMany(QuizAttempt, { as: "attempts", foreignKey: "assessment_id" });

// ── AssessmentSession ─────────────────────────────────────────────────────────
AssessmentSession.belongsTo(CourseAssessment, { as: "assessment", foreignKey: "assessment_id" });
AssessmentSession.belongsTo(mdl_Users,        { as: "user",       foreignKey: "user_id" });
CourseAssessment.hasMany(AssessmentSession,   { as: "sessions",   foreignKey: "assessment_id" });

module.exports = {
    Course, CourseProductCategory,
    Unit, Lesson, LessonPage,
    CourseObjective, LessonObjective,
    CoursePrerequisite, CourseAssessment,
    UnitQuiz, QuizQuestion, QuizOption, QuizAttempt,
    AssessmentSession,
    mdl_Category, Certificate, CourseInstructor,
    CourseReadingProgress,
};