// ABOUTME: Entry point for the metrics receiver service.
// ABOUTME: HTTP service using Fuego framework with automatic OpenAPI 3.0 generation.
package main

import (
	"flag"
	"fmt"
	"log/slog"
	"os"
	"time"

	"github.com/getkin/kin-openapi/openapi3"
	"github.com/go-fuego/fuego"

	"edp.buildth.ing/DevFW-CICD/forgejo-runner-sizer/internal/receiver"
)

const (
	defaultAddr   = ":8080"
	defaultDBPath = "metrics.db"
)

func main() {
	addr := flag.String("addr", defaultAddr, "HTTP listen address")
	dbPath := flag.String("db", defaultDBPath, "SQLite database path")
	readToken := flag.String("read-token", os.Getenv("RECEIVER_READ_TOKEN"), "Pre-shared token for read endpoints (or set RECEIVER_READ_TOKEN)")
	hmacKey := flag.String("hmac-key", os.Getenv("RECEIVER_HMAC_KEY"), "Secret key for push token generation/validation (or set RECEIVER_HMAC_KEY)")
	tokenTTL := flag.Duration("token-ttl", 2*time.Hour, "Time-to-live for push tokens (default 2h)")
	flag.Parse()

	logger := slog.New(slog.NewJSONHandler(os.Stderr, &slog.HandlerOptions{
		Level: slog.LevelInfo,
	}))

	store, err := receiver.NewStore(*dbPath)
	if err != nil {
		logger.Error("failed to open database", slog.String("error", err.Error()))
		os.Exit(1)
	}
	defer func() { _ = store.Close() }()

	handler := receiver.NewHandler(store, logger, *readToken, *hmacKey, *tokenTTL)

	// Create Fuego server with OpenAPI configuration
	s := fuego.NewServer(
		fuego.WithAddr(*addr),
		fuego.WithEngineOptions(
			fuego.WithOpenAPIConfig(fuego.OpenAPIConfig{
				PrettyFormatJSON: true,
				JSONFilePath:     "docs/openapi.json",
				SwaggerURL:       "/swagger",
				Info: &openapi3.Info{
					Title:       "Forgejo Runner Resource Collector API",
					Version:     "1.0.0",
					Description: "HTTP service that receives and stores CI/CD resource metrics from collectors, providing query and sizing recommendation APIs.",
					Contact: &openapi3.Contact{
						Name: "API Support",
						URL:  "https://edp.buildth.ing/DevFW-CICD/forgejo-runner-sizer",
					},
					License: &openapi3.License{
						Name: "Apache 2.0",
						URL:  "http://www.apache.org/licenses/LICENSE-2.0.html",
					},
				},
			}),
		),
	)

	// Register routes
	handler.RegisterRoutes(s)

	logger.Info("starting metrics receiver",
		slog.String("addr", *addr),
		slog.String("db", *dbPath),
		slog.String("swagger", fmt.Sprintf("http://localhost%s/swagger", *addr)),
	)

	// Run server (handles graceful shutdown)
	if err := s.Run(); err != nil {
		fmt.Fprintf(os.Stderr, "error: %v\n", err)
		os.Exit(1)
	}
}