// kjv-api: the King James Bible web API as one program plus one SQLite
// database (kjv.db) that holds the text, every page and asset, user data and
// the logs.
package main

import (
	"flag"
	"fmt"
	"os"
	"path/filepath"

	"kjv-api/internal/kjv"
)

const usage = `usage:
  kjv-api [-db kjv.db] [-addr 127.0.0.1:1611]       run the server
  kjv-api import-assets [-db kjv.db] DIR   load the pages, scripts, styles and data files from the assets folder into the database
  kjv-api logs [-db kjv.db] [-n 100]       print the newest log lines stored in the database
`

func findDB(flagValue string) string {
	if flagValue != "" {
		return flagValue
	}
	if v := os.Getenv("KJV_DB"); v != "" {
		return v
	}
	candidates := []string{"kjv.db"}
	if exe, err := os.Executable(); err == nil {
		candidates = append(candidates, filepath.Join(filepath.Dir(exe), "kjv.db"))
	}
	for _, c := range candidates {
		if _, err := os.Stat(c); err == nil {
			return c
		}
	}
	return "kjv.db"
}

func main() {
	args := os.Args[1:]
	if len(args) > 0 {
		switch args[0] {
		case "import-assets":
			fs := flag.NewFlagSet("import-assets", flag.ExitOnError)
			db := fs.String("db", "", "path to kjv.db")
			fs.Parse(args[1:])
			if fs.NArg() != 1 {
				fmt.Fprint(os.Stderr, usage)
				os.Exit(2)
			}
			dbPath := findDB(*db)
			if _, err := os.Stat(dbPath); err != nil {
				fatal(err)
			}
			if err := kjv.ImportAssets(dbPath, fs.Arg(0)); err != nil {
				fatal(err)
			}
			return
		case "logs":
			fs := flag.NewFlagSet("logs", flag.ExitOnError)
			db := fs.String("db", "", "path to kjv.db")
			n := fs.Int("n", 100, "number of lines")
			fs.Parse(args[1:])
			if err := kjv.ShowLogs(findDB(*db), *n); err != nil {
				fatal(err)
			}
			return
		case "help", "-h", "--help":
			fmt.Print(usage)
			return
		}
	}
	fs := flag.NewFlagSet("kjv-api", flag.ExitOnError)
	dbFlag := fs.String("db", "", "path to kjv.db (default: $KJV_DB, ./kjv.db, next to the program)")
	addr := fs.String("addr", envOr("KJV_ADDR", "127.0.0.1:1611"), "listen address (localhost only)")
	fs.Parse(args)
	if err := kjv.Run(findDB(*dbFlag), *addr); err != nil {
		fatal(err)
	}
}

func fatal(err error) {
	fmt.Fprintln(os.Stderr, "kjv-api:", err)
	os.Exit(1)
}

func envOr(key, def string) string {
	if v := os.Getenv(key); v != "" {
		return v
	}
	return def
}