// This example uses only local HTTP and simulated work; no external services.
package main

import (
	"context"
	"errors"
	"flag"
	"io"
	"log"
	"os"
	"os/signal"
	"syscall"
	"time"

	omni "git.yuntuo.hk/k2safe/go-omni"
	"git.yuntuo.hk/k2safe/go-omni/lifecycle"
)

func main() {
	address := flag.String("addr", "127.0.0.1:8080", "local listen address")
	flag.Parse()
	ctx, stop := signal.NotifyContext(context.Background(), os.Interrupt, syscall.SIGTERM)
	defer stop()
	if err := run(ctx, *address); err != nil {
		log.Print(err)
		os.Exit(1)
	}
}

func run(ctx context.Context, address string) (runErr error) {
	deps := lifecycle.NewRuntime(ctx)
	deps.OnClose(func() error { log.Print("shared resource closed after requests completed"); return nil })
	defer func() { runErr = deps.Finish(runErr) }()
	app := omni.New(omni.WithHTTPConfig(omni.HTTPConfig{
		DefaultMaxBodyBytes:   1 << 20,
		MaxBodyBytes:          20 << 20,
		ShutdownCancelTimeout: time.Second,
	}), omni.WithShutdownTimeout(time.Second))
	defer func() { runErr = errors.Join(runErr, app.Close()) }()
	app.HandleWithBodyLimit("POST", "/upload", 16<<20, nil, func(c *omni.Context) error {
		n, err := io.Copy(io.Discard, c.Request().Body)
		if err != nil {
			return err
		}
		return c.OK(map[string]int64{"bytes": n})
	})
	app.GET("/work", func(c *omni.Context) error {
		log.Print("request accepted")
		select {
		case <-time.After(10 * time.Second):
			return c.OK("finished")
		case <-c.Context().Done():
			// Simulate bounded rollback/cleanup after cancellation. Dependencies
			// remain available until this handler and its defers have returned.
			time.Sleep(100 * time.Millisecond)
			log.Print("request cleanup completed")
			return c.Context().Err()
		}
	})
	log.Printf("listening on %s; POST /upload or GET /work, then Ctrl-C", address)
	return app.RunContext(deps.Context(), address)
}