package app

import (
	"context"
	"errors"
	"log/slog"
	"net/http"
	"os"
	"os/signal"
	"syscall"

	"git.michelsen.id/phill/preface-tools/internal/auth"
	"git.michelsen.id/phill/preface-tools/internal/httpserver"
	"git.michelsen.id/phill/preface-tools/internal/tools"
	"git.michelsen.id/phill/preface-tools/internal/tools/comicanimator"
)

func Run() error {
	cfg, err := LoadConfigFromEnv()
	if err != nil {
		return err
	}
	comicCfg, err := comicanimator.LoadConfigFromEnv()
	if err != nil {
		return err
	}
	var handler slog.Handler = slog.NewTextHandler(os.Stdout, nil)
	if cfg.LogFormat == "json" {
		handler = slog.NewJSONHandler(os.Stdout, nil)
	}
	log := slog.New(handler)
	a := auth.New(cfg.StudentPIN, cfg.InstructorPIN, cfg.SessionSecret, cfg.SessionDuration, cfg.Environment == "production")
	comic, err := comicanimator.New(comicCfg, log, a)
	if err != nil {
		return err
	}
	registry := tools.NewRegistry()
	if err = registry.Register(comic); err != nil {
		return err
	}
	srv := &http.Server{Addr: cfg.Address, Handler: httpserver.New(a, registry, log).Handler(), ReadHeaderTimeout: cfg.ReadHeaderTimeout, ReadTimeout: cfg.ReadTimeout, WriteTimeout: cfg.WriteTimeout, IdleTimeout: cfg.IdleTimeout}
	ctx, stop := signal.NotifyContext(context.Background(), os.Interrupt, syscall.SIGTERM)
	defer stop()
	workerDone := make(chan error, 1)
	go func() { workerDone <- comic.Run(ctx) }()
	serverDone := make(chan error, 1)
	go func() { log.Info("server starting", "address", cfg.Address); serverDone <- srv.ListenAndServe() }()
	select {
	case err = <-serverDone:
		if !errors.Is(err, http.ErrServerClosed) {
			stop()
			return err
		}
	case <-ctx.Done():
	}
	shutdownCtx, cancel := context.WithTimeout(context.Background(), cfg.ShutdownTimeout)
	defer cancel()
	if err := srv.Shutdown(shutdownCtx); err != nil {
		return err
	}
	stop()
	return <-workerDone
}