package main

import (
	"context"
	"fmt"
	"log"
	"net/http"
	"os"
	"thamanyah/discovery/internal/db"
	"thamanyah/discovery/internal/handlers"

	_ "github.com/lib/pq"
	httpSwagger "github.com/swaggo/http-swagger/v2"

	_ "thamanyah/discovery/docs"
)

//	@title			Thamanyah Discovery API
//	@version		1.0
//	@description	JSON API for browsing the Thamanyah catalogue. Read-side counterpart to the CMS, which is what ingests videos.
//	@BasePath		/

func main() {
	if len(os.Args) > 1 && os.Args[1] == "migrate" {
		runMigrate()
		return
	}
	runServer()
}

func runMigrate() {
	concreteDBClient := db.CreateDBConnection(requireDBConnectionString())
	defer db.CloseConnection(concreteDBClient)
	if err := db.Migrate(concreteDBClient); err != nil {
		panic(err)
	}
	log.Println("migrations applied successfully")
}

func runServer() {
	concreteDBClient := db.CreateDBConnection(requireDBConnectionString())
	defer db.CloseConnection(concreteDBClient)
	db.AssertSuccessfulConnection(context.Background(), concreteDBClient)

	mux := http.NewServeMux()

	mux.HandleFunc("GET /health", handlers.Health)

	// Swagger UI and the generated spec. The UI assets are embedded in the
	// binary by swaggo/files, so this needs no static directory on disk.
	mux.Handle("GET /swagger/", httpSwagger.WrapHandler)

	addr := ":8080"
	log.Printf("listening on %s", addr)
	if err := http.ListenAndServe(addr, mux); err != nil {
		log.Fatal(err)
	}
}

func requireDBConnectionString() string {
	dbHost := os.Getenv("DB_HOST")
	if dbHost == "" {
		panic(fmt.Errorf("missing required env var: DB_HOST"))
	}

	dbPort := os.Getenv("DB_PORT")
	if dbPort == "" {
		panic(fmt.Errorf("missing required env var: DB_PORT"))
	}

	dbUser := os.Getenv("DB_USER")
	if dbUser == "" {
		panic(fmt.Errorf("missing required env var: DB_USER"))
	}

	dbPassword := os.Getenv("DB_PASSWORD")
	if dbPassword == "" {
		panic(fmt.Errorf("missing required env var: DB_PASSWORD"))
	}

	dbName := os.Getenv("DB_NAME")
	if dbName == "" {
		panic(fmt.Errorf("missing required env var: DB_NAME"))
	}

	// Defaults to require: RDS terminates TLS, and only a local Postgres that
	// serves none (LocalStack's RDS emulation) has any business overriding it.
	dbSSLMode := os.Getenv("DB_SSLMODE")
	if dbSSLMode == "" {
		dbSSLMode = "require"
	}

	return fmt.Sprintf(
		"host=%s port=%s user=%s password=%s dbname=%s sslmode=%s",
		dbHost, dbPort, dbUser, dbPassword, dbName, dbSSLMode,
	)
}