package main

import (
	"context"
	"log"
	"os"

	"github.com/breakpilot/school-service/internal/config"
	"github.com/breakpilot/school-service/internal/database"
	"github.com/breakpilot/school-service/internal/handlers"
	"github.com/breakpilot/school-service/internal/middleware"
	"github.com/gin-gonic/gin"
)

func main() {
	// Load configuration
	cfg, err := config.Load()
	if err != nil {
		log.Fatalf("Failed to load configuration: %v", err)
	}

	// Set Gin mode based on environment
	if cfg.Environment == "production" {
		gin.SetMode(gin.ReleaseMode)
	}

	// Connect to database
	db, err := database.Connect(cfg.DatabaseURL)
	if err != nil {
		log.Fatalf("Failed to connect to database: %v", err)
	}
	defer db.Close()

	// Run migrations
	if err := database.Migrate(db); err != nil {
		log.Fatalf("Failed to run migrations: %v", err)
	}

	// Create handler
	handler := handlers.NewHandler(db.Pool, cfg.LLMGatewayURL, cfg.SolverServiceURL)

	// Calendar seed — idempotent, runs every boot. Snapshot path is bundled
	// in the Docker image at /app/internal/seed/calendar_holidays.json. Failures
	// don't block startup; the holiday table is filled lazily next boot.
	go func() {
		seedPath := "internal/seed/calendar_holidays.json"
		if _, err := os.Stat(seedPath); err != nil {
			seedPath = "/app/internal/seed/calendar_holidays.json"
		}
		if err := handler.CalendarService().SeedFromSnapshot(context.Background(), seedPath); err != nil {
			log.Printf("calendar seed failed: %v", err)
		}
	}()

	// Create router
	router := gin.New()
	router.Use(gin.Recovery())
	router.Use(middleware.RequestLogger())
	router.Use(middleware.CORS())
	router.Use(middleware.RateLimiter())

	// Health endpoint (no auth required)
	router.GET("/health", handler.Health)

	// API routes (auth required)
	api := router.Group("/api/v1/school")
	api.Use(middleware.AuthMiddleware(cfg.JWTSecret, cfg.Environment != "production"))
	{
		// School Years
		api.GET("/years", handler.GetSchoolYears)
		api.POST("/years", handler.CreateSchoolYear)

		// Classes
		api.GET("/classes", handler.GetClasses)
		api.POST("/classes", handler.CreateClass)
		api.GET("/classes/:id", handler.GetClass)
		api.DELETE("/classes/:id", handler.DeleteClass)

		// Students (nested under classes)
		api.GET("/classes/:id/students", handler.GetStudents)
		api.POST("/classes/:id/students", handler.CreateStudent)
		api.POST("/classes/:id/students/import", handler.ImportStudents)
		api.DELETE("/classes/:id/students/:studentId", handler.DeleteStudent)

		// Subjects
		api.GET("/subjects", handler.GetSubjects)
		api.POST("/subjects", handler.CreateSubject)
		api.DELETE("/subjects/:id", handler.DeleteSubject)

		// Exams
		api.GET("/exams", handler.GetExams)
		api.POST("/exams", handler.CreateExam)
		api.GET("/exams/:id", handler.GetExam)
		api.PUT("/exams/:id", handler.UpdateExam)
		api.DELETE("/exams/:id", handler.DeleteExam)
		api.POST("/exams/:id/generate-variant", handler.GenerateExamVariant)
		api.GET("/exams/:id/results", handler.GetExamResults)
		api.POST("/exams/:id/results", handler.SaveExamResults)
		api.PUT("/exams/:id/results/:studentId/approve", handler.ApproveExamResult)
		api.GET("/exams/:id/needs-rewrite", handler.GetStudentsNeedingRewrite)

		// Grades
		api.GET("/grades/:classId", handler.GetClassGrades)
		api.GET("/grades/student/:studentId", handler.GetStudentGrades)
		api.PUT("/grades/:studentId/:subjectId/oral", handler.UpdateOralGrade)
		api.POST("/grades/calculate", handler.CalculateFinalGrades)
		api.POST("/grades/transfer", handler.TransferApprovedGrades)
		api.PUT("/grades/:studentId/:subjectId/lock", handler.LockFinalGrade)
		api.PUT("/grades/:studentId/:subjectId/weights", handler.UpdateGradeWeights)

		// Statistics
		api.GET("/statistics/:classId", handler.GetClassStatistics)
		api.GET("/statistics/:classId/subject/:subjectId", handler.GetSubjectStatistics)
		api.GET("/statistics/student/:studentId", handler.GetStudentStatistics)
		api.GET("/statistics/:classId/notenspiegel", handler.GetNotenspiegel)

		// Attendance
		api.GET("/attendance/:classId", handler.GetClassAttendance)
		api.GET("/attendance/student/:studentId", handler.GetStudentAttendance)
		api.POST("/attendance", handler.CreateAttendance)
		api.POST("/attendance/:classId/bulk", handler.BulkCreateAttendance)
		api.DELETE("/attendance/:id", handler.DeleteAttendance)

		// Gradebook Entries
		api.GET("/gradebook/:classId", handler.GetGradebookEntries)
		api.GET("/gradebook/student/:studentId", handler.GetStudentEntries)
		api.POST("/gradebook", handler.CreateGradebookEntry)
		api.DELETE("/gradebook/:id", handler.DeleteGradebookEntry)

		// Certificates
		api.GET("/certificates/templates", handler.GetCertificateTemplates)
		api.GET("/certificates/class/:classId", handler.GetClassCertificates)
		api.GET("/certificates/feedback/:studentId", handler.GenerateGradeFeedback)
		api.POST("/certificates/generate", handler.GenerateCertificate)
		api.POST("/certificates/generate-bulk", handler.BulkGenerateCertificates)
		api.GET("/certificates/detail/:id", handler.GetCertificate)
		api.PUT("/certificates/detail/:id", handler.UpdateCertificate)
		api.PUT("/certificates/detail/:id/finalize", handler.FinalizeCertificate)
		api.GET("/certificates/detail/:id/pdf", handler.GetCertificatePDF)
		api.DELETE("/certificates/detail/:id", handler.DeleteCertificate)

		// Timetable Scheduler — Stammdaten
		api.GET("/timetable/classes", handler.ListTimetableClasses)
		api.POST("/timetable/classes", handler.CreateTimetableClass)
		api.DELETE("/timetable/classes/:id", handler.DeleteTimetableClass)

		api.GET("/timetable/periods", handler.ListTimetablePeriods)
		api.POST("/timetable/periods", handler.CreateTimetablePeriod)
		api.DELETE("/timetable/periods/:id", handler.DeleteTimetablePeriod)

		api.GET("/timetable/rooms", handler.ListTimetableRooms)
		api.POST("/timetable/rooms", handler.CreateTimetableRoom)
		api.DELETE("/timetable/rooms/:id", handler.DeleteTimetableRoom)

		api.GET("/timetable/subjects", handler.ListTimetableSubjects)
		api.POST("/timetable/subjects", handler.CreateTimetableSubject)
		api.DELETE("/timetable/subjects/:id", handler.DeleteTimetableSubject)

		api.GET("/timetable/teachers", handler.ListTimetableTeachers)
		api.POST("/timetable/teachers", handler.CreateTimetableTeacher)
		api.DELETE("/timetable/teachers/:id", handler.DeleteTimetableTeacher)

		// Timetable Scheduler — Relations
		api.GET("/timetable/curriculum", handler.ListTimetableCurriculum)
		api.POST("/timetable/curriculum", handler.CreateTimetableCurriculum)
		api.DELETE("/timetable/curriculum/:id", handler.DeleteTimetableCurriculum)

		api.GET("/timetable/assignments", handler.ListTimetableAssignments)
		api.POST("/timetable/assignments", handler.CreateTimetableAssignment)
		api.DELETE("/timetable/assignments/:id", handler.DeleteTimetableAssignment)

		// Timetable Scheduler — Constraints (15 typed tables)
		// Teacher
		api.GET("/timetable/constraints/teacher/unavailable-day", handler.ListTeacherUnavailableDays)
		api.POST("/timetable/constraints/teacher/unavailable-day", handler.CreateTeacherUnavailableDay)
		api.DELETE("/timetable/constraints/teacher/unavailable-day/:id", handler.DeleteTeacherUnavailableDay)

		api.GET("/timetable/constraints/teacher/unavailable-window", handler.ListTeacherUnavailableWindows)
		api.POST("/timetable/constraints/teacher/unavailable-window", handler.CreateTeacherUnavailableWindow)
		api.DELETE("/timetable/constraints/teacher/unavailable-window/:id", handler.DeleteTeacherUnavailableWindow)

		api.GET("/timetable/constraints/teacher/max-hours-day", handler.ListTeacherMaxHoursDay)
		api.POST("/timetable/constraints/teacher/max-hours-day", handler.CreateTeacherMaxHoursDay)
		api.DELETE("/timetable/constraints/teacher/max-hours-day/:id", handler.DeleteTeacherMaxHoursDay)

		api.GET("/timetable/constraints/teacher/max-hours-week", handler.ListTeacherMaxHoursWeek)
		api.POST("/timetable/constraints/teacher/max-hours-week", handler.CreateTeacherMaxHoursWeek)
		api.DELETE("/timetable/constraints/teacher/max-hours-week/:id", handler.DeleteTeacherMaxHoursWeek)

		api.GET("/timetable/constraints/teacher/excluded-subject", handler.ListTeacherExcludedSubjects)
		api.POST("/timetable/constraints/teacher/excluded-subject", handler.CreateTeacherExcludedSubject)
		api.DELETE("/timetable/constraints/teacher/excluded-subject/:id", handler.DeleteTeacherExcludedSubject)

		api.GET("/timetable/constraints/teacher/excluded-room", handler.ListTeacherExcludedRooms)
		api.POST("/timetable/constraints/teacher/excluded-room", handler.CreateTeacherExcludedRoom)
		api.DELETE("/timetable/constraints/teacher/excluded-room/:id", handler.DeleteTeacherExcludedRoom)

		// Subject
		api.GET("/timetable/constraints/subject/min-day-gap", handler.ListSubjectMinDayGaps)
		api.POST("/timetable/constraints/subject/min-day-gap", handler.CreateSubjectMinDayGap)
		api.DELETE("/timetable/constraints/subject/min-day-gap/:id", handler.DeleteSubjectMinDayGap)

		api.GET("/timetable/constraints/subject/max-consecutive", handler.ListSubjectMaxConsecutives)
		api.POST("/timetable/constraints/subject/max-consecutive", handler.CreateSubjectMaxConsecutive)
		api.DELETE("/timetable/constraints/subject/max-consecutive/:id", handler.DeleteSubjectMaxConsecutive)

		api.GET("/timetable/constraints/subject/contiguous-when-repeated", handler.ListSubjectContiguousWhenRepeated)
		api.POST("/timetable/constraints/subject/contiguous-when-repeated", handler.CreateSubjectContiguousWhenRepeated)
		api.DELETE("/timetable/constraints/subject/contiguous-when-repeated/:id", handler.DeleteSubjectContiguousWhenRepeated)

		api.GET("/timetable/constraints/subject/preferred-period", handler.ListSubjectPreferredPeriods)
		api.POST("/timetable/constraints/subject/preferred-period", handler.CreateSubjectPreferredPeriod)
		api.DELETE("/timetable/constraints/subject/preferred-period/:id", handler.DeleteSubjectPreferredPeriod)

		api.GET("/timetable/constraints/subject/double-lesson", handler.ListSubjectDoubleLessons)
		api.POST("/timetable/constraints/subject/double-lesson", handler.CreateSubjectDoubleLesson)
		api.DELETE("/timetable/constraints/subject/double-lesson/:id", handler.DeleteSubjectDoubleLesson)

		// Class
		api.GET("/timetable/constraints/class/max-hours-day", handler.ListClassMaxHoursDay)
		api.POST("/timetable/constraints/class/max-hours-day", handler.CreateClassMaxHoursDay)
		api.DELETE("/timetable/constraints/class/max-hours-day/:id", handler.DeleteClassMaxHoursDay)

		api.GET("/timetable/constraints/class/no-gaps", handler.ListClassNoGaps)
		api.POST("/timetable/constraints/class/no-gaps", handler.CreateClassNoGaps)
		api.DELETE("/timetable/constraints/class/no-gaps/:id", handler.DeleteClassNoGaps)

		// Room
		api.GET("/timetable/constraints/room/requires-type", handler.ListRoomRequiresTypes)
		api.POST("/timetable/constraints/room/requires-type", handler.CreateRoomRequiresType)
		api.DELETE("/timetable/constraints/room/requires-type/:id", handler.DeleteRoomRequiresType)

		api.GET("/timetable/constraints/room/unavailable", handler.ListRoomUnavailable)
		api.POST("/timetable/constraints/room/unavailable", handler.CreateRoomUnavailable)
		api.DELETE("/timetable/constraints/room/unavailable/:id", handler.DeleteRoomUnavailable)

		// Timetable Solver — Solutions
		api.GET("/timetable/solutions", handler.ListTimetableSolutions)
		api.POST("/timetable/solutions", handler.CreateTimetableSolution)
		api.GET("/timetable/solutions/:id", handler.GetTimetableSolution)
		api.DELETE("/timetable/solutions/:id", handler.DeleteTimetableSolution)
		api.GET("/timetable/solutions/:id/lessons", handler.ListTimetableLessons)

		// Phase 7: pin/unpin individual lessons for the next re-solve.
		api.PUT("/timetable/lessons/:id/pin", handler.UpdateTimetableLessonPin)

		// Phase 8: exports.
		api.GET("/timetable/solutions/:id/export.csv", handler.ExportTimetableSolutionCSV)
		api.GET("/timetable/solutions/:id/export.ics", handler.ExportTimetableSolutionICS)

		// Phase 9a: Schulkalender (holidays + per-user Bundesland config).
		api.GET("/calendar/holidays", handler.ListCalendarHolidays)
		api.GET("/calendar/config", handler.GetCalendarConfig)
		api.PUT("/calendar/config", handler.UpsertCalendarConfig)

		// Phase 9b: school-events CRUD + Schuljahres-Rollover.
		api.GET("/calendar/events", handler.ListSchoolEvents)
		api.POST("/calendar/events", handler.CreateSchoolEvent)
		api.DELETE("/calendar/events/:id", handler.DeleteSchoolEvent)
		api.POST("/calendar/school-year-rollover", handler.RolloverSchoolYear)

		// Phase 9c: parent invitations (teacher side).
		api.GET("/calendar/parents", handler.ListParentInvites)
		api.POST("/calendar/parents/invite", handler.InviteParent)
		api.DELETE("/calendar/parents/children/:id", handler.DeleteParentInvite)
	}

	// Phase 9c: parent-side endpoints. Auth is the parent session cookie,
	// NOT the teacher JWT. /parent/auth/redeem creates the cookie; the
	// other routes require it via ParentSessionMiddleware.
	parentAPI := router.Group("/api/v1/parent")
	{
		parentAPI.POST("/auth/redeem", handler.RedeemMagicLink)

		authed := parentAPI.Group("/")
		authed.Use(middleware.ParentSessionMiddleware(func(ctx context.Context, token string) (string, string, string, error) {
			p, err := handler.ParentService().ParentFromSession(ctx, token)
			if err != nil {
				return "", "", "", err
			}
			return p.ID.String(), p.Email, p.PreferredLanguage, nil
		}))
		authed.GET("/me", handler.ParentMe)
		authed.GET("/me/timetable", handler.ParentTimetable)
		authed.POST("/auth/logout", handler.ParentLogout)
	}

	// Start server
	log.Printf("School Service starting on port %s", cfg.Port)
	if err := router.Run(":" + cfg.Port); err != nil {
		log.Fatalf("Failed to start server: %v", err)
	}
}