package main

import (
	"context"
	"errors"
	"flag"
	"html/template"
	"log"
	"os"
	"os/signal"
	"path/filepath"
	"strings"
	"syscall"
	"time"

	"misaki/db"
	"misaki/server"

	"github.com/BurntSushi/toml"
)

type fileCfg struct {
	Addr           string                `toml:"addr"`
	DB             string                `toml:"db"`
	InternalSecret string                `toml:"internal_secret"`
	AuthSecret     string                `toml:"auth_secret"`
	BaseDomain     string                `toml:"base_domain"`
	DefaultNote    string                `toml:"default_note"`
	PublicURL      string                `toml:"public_url"`
	TOTPKeyFile    string                `toml:"totp_key_file"`
	SMTP           smtpFileCfg           `toml:"smtp"`
	OIDC           oidcFileCfg           `toml:"oidc"`
	Services       map[string]svcFileCfg `toml:"services"`
}

type smtpFileCfg struct {
	Host        string `toml:"host"`
	User        string `toml:"user"`
	Pass        string `toml:"pass"`
	From        string `toml:"from"`
	NotifyEmail string `toml:"notify_email"`
	TLSName     string `toml:"tls_name"`
}

type oidcFileCfg struct {
	Issuer  string                       `toml:"issuer"`
	KeyFile string                       `toml:"key_file"`
	Clients map[string]oidcClientFileCfg `toml:"clients"`
}

type oidcClientFileCfg struct {
	SecretSHA256 string   `toml:"secret_sha256"`
	RedirectURIs []string `toml:"redirect_uris"`
	Service      string   `toml:"service"`
	RequireEmail bool     `toml:"require_email"`
}

type svcFileCfg struct {
	Enabled *bool  `toml:"enabled"`
	Desc    string `toml:"desc"`
	InfoURL string `toml:"info_url"`
	URL     string `toml:"url"`
	Host    string `toml:"host"`
	User    string `toml:"user"`
	Pass    string `toml:"pass"`
}

func main() {
	configPath := flag.String("config", "", "path to TOML config file (optional)")
	addrFlag := flag.String("addr", "", "listen address (default :8080)")
	dbFlag := flag.String("db", "", "sqlite database path (default /data/misaki.db)")
	defaultNoteFlag := flag.String("default-note", "", "default note for new users (default: \"I love misaki!\")")

	gancioURL := flag.String("gancio-url", "", "Gancio registration page URL")
	akkomaURL := flag.String("akkoma-url", "", "Akkoma registration page URL")
	prosodyURL := flag.String("prosody-url", "", "Prosody registration page URL")
	forgejoURL := flag.String("forgejo-url", "", "Forgejo registration page URL")

	mumbleHost := flag.String("mumble-host", "", "Mumble server host:port")
	mumblePass := flag.String("mumble-pass", "", "Mumble server password")
	transferHost := flag.String("transfer-host", "", "Transfer.sh host URL")
	transferUser := flag.String("transfer-user", "", "Transfer.sh username")
	transferPass := flag.String("transfer-pass", "", "Transfer.sh password")

	mailEnabled := flag.String("mail-enabled", "", "globally enable/disable mail (1/0)")
	mailDesc := flag.String("mail-desc", "", "HTML description for Mail")
	wercEnabled := flag.String("werc-enabled", "", "globally enable/disable werc (1/0)")
	wercDesc := flag.String("werc-desc", "", "HTML description for Werc")
	ergoEnabled := flag.String("ergo-enabled", "", "globally enable/disable ergo (1/0)")
	ergoDesc := flag.String("ergo-desc", "", "HTML description for Ergo")
	gancioEnabled := flag.String("gancio-enabled", "", "globally enable/disable gancio (1/0)")
	gancioDesc := flag.String("gancio-desc", "", "HTML description for Gancio")
	akkomaEnabled := flag.String("akkoma-enabled", "", "globally enable/disable akkoma (1/0)")
	akkomaDesc := flag.String("akkoma-desc", "", "HTML description for Akkoma")
	prosodyEnabled := flag.String("prosody-enabled", "", "globally enable/disable prosody (1/0)")
	prosodyDesc := flag.String("prosody-desc", "", "HTML description for Prosody")
	forgejoEnabled := flag.String("forgejo-enabled", "", "globally enable/disable forgejo (1/0)")
	forgejoDesc := flag.String("forgejo-desc", "", "HTML description for Forgejo")
	cercaEnabled := flag.String("cerca-enabled", "", "globally enable/disable cerca (1/0)")
	cercaDesc := flag.String("cerca-desc", "", "HTML description for Cerca")
	mumbleEnabled := flag.String("mumble-enabled", "", "globally enable/disable mumble (1/0)")
	mumbleDesc := flag.String("mumble-desc", "", "HTML description for Mumble")
	transferEnabled := flag.String("transfer-enabled", "", "globally enable/disable transfer (1/0)")
	transferDesc := flag.String("transfer-desc", "", "HTML description for Transfer")
	streamingEnabled := flag.String("streaming-enabled", "", "globally enable/disable streaming (1/0)")
	streamingDesc := flag.String("streaming-desc", "", "HTML description for Streaming")
	radioEnabled := flag.String("radio-enabled", "", "globally enable/disable radio (1/0)")
	radioDesc := flag.String("radio-desc", "", "HTML description for Radio")
	filesEnabled := flag.String("files-enabled", "", "globally enable/disable files (1/0)")
	filesDesc := flag.String("files-desc", "", "HTML description for Files")

	notesEnabled := flag.String("notes-enabled", "", "globally enable/disable notes (1/0)")
	notesDesc    := flag.String("notes-desc",    "", "HTML description for HedgeDoc")
	notesURL     := flag.String("notes-url",     "", "HedgeDoc URL")
	pasteEnabled := flag.String("paste-enabled", "", "globally enable/disable paste (1/0)")
	pasteDesc    := flag.String("paste-desc",    "", "HTML description for PrivateBin")
	pasteURL     := flag.String("paste-url",     "", "PrivateBin URL")
	rssEnabled   := flag.String("rss-enabled",   "", "globally enable/disable rss (1/0)")
	rssDesc      := flag.String("rss-desc",      "", "HTML description for RSS Bridge")
	rssURL       := flag.String("rss-url",       "", "RSS Bridge URL")

	smtpHost := flag.String("smtp-host", "", "SMTP host:port e.g. smtp.example.com:587")
	smtpUser := flag.String("smtp-user", "", "SMTP username")
	smtpPass := flag.String("smtp-pass", "", "SMTP password (or SMTP_PASS env)")
	smtpFrom := flag.String("smtp-from", "", "From address for notification emails")
	notifyTo := flag.String("notify-email", "", "Address to receive notifications")
	smtpTLSName := flag.String("smtp-tls-name", "", "Hostname for TLS cert verification (useful when connecting via internal hostname)")

	internalSecret := flag.String("internal-secret", "", "bearer token protecting POST /internal/auth (leave empty to disable)")
	authSecret := flag.String("auth-secret", "", "HMAC secret for signing session-check identity (shared with werc; leave empty to disable signing)")
	baseDomain := flag.String("base-domain", "", "base domain for allowed post-login redirects (e.g. example.com)")
	secureCookiesFlag := flag.Bool("secure-cookies", false, "set Secure flag on session cookies (enable when serving over HTTPS)")

	flag.Parse()

	var cfg fileCfg
	if path := firstNonEmpty(*configPath, os.Getenv("CONFIG_FILE")); path != "" {
		if _, err := toml.DecodeFile(path, &cfg); err != nil {
			if errors.Is(err, os.ErrNotExist) {
				log.Printf("config file %q not found, using flags/env only", path)
			} else {
				log.Fatalf("load config %q: %v", path, err)
			}
		} else {
			log.Printf("loaded config from %s", path)
		}
	}

	cfgOr := func(flagVal, envKey, cfgVal string) string {
		return firstNonEmpty(flagVal, os.Getenv(envKey), cfgVal)
	}

	svc := func(name string) svcFileCfg { return cfg.Services[name] }

	resolveEnabled := func(flagVal, envKey string, cfgEnabled *bool) string {
		if flagVal != "" {
			return flagVal
		}
		if ev := os.Getenv(envKey); ev != "" {
			return ev
		}
		if cfgEnabled != nil {
			if *cfgEnabled {
				return "1"
			}
			return "0"
		}
		return ""
	}

	dbPath := firstNonEmpty(*dbFlag, os.Getenv("DB_PATH"), cfg.DB, "/data/misaki.db")
	database, err := db.Open(dbPath)
	if err != nil {
		log.Fatalf("open db: %v", err)
	}

	type svcSeed struct {
		name        string
		flagEnabled string
		envEnabled  string
		cfgSvc      svcFileCfg
		flagDesc    string
		envDesc     string
	}
	seeds := []svcSeed{
		{"mail", *mailEnabled, "MAIL_ENABLED", svc("mail"), *mailDesc, "MAIL_DESC"},
		{"werc", *wercEnabled, "WERC_ENABLED", svc("werc"), *wercDesc, "WERC_DESC"},
		{"ergo", *ergoEnabled, "ERGO_ENABLED", svc("ergo"), *ergoDesc, "ERGO_DESC"},
		{"gancio", *gancioEnabled, "GANCIO_ENABLED", svc("gancio"), *gancioDesc, "GANCIO_DESC"},
		{"akkoma", *akkomaEnabled, "AKKOMA_ENABLED", svc("akkoma"), *akkomaDesc, "AKKOMA_DESC"},
		{"pixelfed", "", "PIXELFED_ENABLED", svc("pixelfed"), "", "PIXELFED_DESC"},
		{"prosody", *prosodyEnabled, "PROSODY_ENABLED", svc("prosody"), *prosodyDesc, "PROSODY_DESC"},
		{"forgejo", *forgejoEnabled, "FORGEJO_ENABLED", svc("forgejo"), *forgejoDesc, "FORGEJO_DESC"},
		{"cerca", *cercaEnabled, "CERCA_ENABLED", svc("cerca"), *cercaDesc, "CERCA_DESC"},
		{"mumble", *mumbleEnabled, "MUMBLE_ENABLED", svc("mumble"), *mumbleDesc, "MUMBLE_DESC"},
		{"transfer", *transferEnabled, "TRANSFER_ENABLED", svc("transfer"), *transferDesc, "TRANSFER_DESC"},
		{"streaming", *streamingEnabled, "STREAMING_ENABLED", svc("streaming"), *streamingDesc, "STREAMING_DESC"},
		{"radio",     *radioEnabled,     "RADIO_ENABLED",     svc("radio"),     *radioDesc,     "RADIO_DESC"},
		{"files",     *filesEnabled,     "FILES_ENABLED",     svc("files"),     *filesDesc,     "FILES_DESC"},
		{"notes",     *notesEnabled,     "NOTES_ENABLED",     svc("notes"),     *notesDesc,     "NOTES_DESC"},
		{"paste",     *pasteEnabled,     "PASTE_ENABLED",     svc("paste"),     *pasteDesc,     "PASTE_DESC"},
		{"rss",       *rssEnabled,       "RSS_ENABLED",       svc("rss"),       *rssDesc,       "RSS_DESC"},
	}

	svcDescs := make(map[string]template.HTML)
	for _, s := range seeds {
		switch strings.ToLower(resolveEnabled(s.flagEnabled, s.envEnabled, s.cfgSvc.Enabled)) {
		case "1", "true":
			if err := database.SetServiceEnabled(s.name, true); err != nil {
				log.Printf("enable %s: %v", s.name, err)
			}
		case "0", "false":
			if err := database.SetServiceEnabled(s.name, false); err != nil {
				log.Printf("disable %s: %v", s.name, err)
			}
		}
		if desc := cfgOr(s.flagDesc, s.envDesc, s.cfgSvc.Desc); desc != "" {
			svcDescs[s.name] = template.HTML(desc)
		}
	}

	infoURLs := make(map[string]string)
	for _, s := range seeds {
		if u := firstNonEmpty(os.Getenv(strings.ToUpper(s.name)+"_INFO_URL"), s.cfgSvc.InfoURL); u != "" {
			infoURLs[s.name] = u
		}
	}

	svcURLs := server.ServiceURLs{
		GancioURL:    cfgOr(*gancioURL, "GANCIO_URL", svc("gancio").URL),
		AkkomaURL:    cfgOr(*akkomaURL, "AKKOMA_URL", svc("akkoma").URL),
		ProsodyURL:   cfgOr(*prosodyURL, "PROSODY_URL", svc("prosody").URL),
		ForgejoURL:   cfgOr(*forgejoURL, "FORGEJO_URL", svc("forgejo").URL),
		MumbleHost:   cfgOr(*mumbleHost, "MUMBLE_HOST", svc("mumble").Host),
		MumblePass:   cfgOr(*mumblePass, "MUMBLE_PASS", svc("mumble").Pass),
		TransferHost: cfgOr(*transferHost, "TRANSFER_HOST", svc("transfer").Host),
		TransferUser: cfgOr(*transferUser, "TRANSFER_USER", svc("transfer").User),
		TransferPass: cfgOr(*transferPass, "TRANSFER_PASS", svc("transfer").Pass),
	}

	smtpCfg := server.SMTPConfig{
		Host: cfgOr(*smtpHost, "SMTP_HOST", cfg.SMTP.Host),
		User: cfgOr(*smtpUser, "SMTP_USER", cfg.SMTP.User),
		Pass: cfgOr(*smtpPass, "SMTP_PASS", cfg.SMTP.Pass),
		From: cfgOr(*smtpFrom, "SMTP_FROM", cfg.SMTP.From),
		To:      cfgOr(*notifyTo, "NOTIFY_EMAIL", cfg.SMTP.NotifyEmail),
		TLSName: cfgOr(*smtpTLSName, "SMTP_TLS_NAME", cfg.SMTP.TLSName),
	}
	if smtpCfg.Host == "" {
		log.Printf("smtp: not configured — emails will be skipped")
	} else if smtpCfg.To == "" {
		log.Printf("smtp: host=%s from=%s (warning: no notify_email set, admin notifications disabled)", smtpCfg.Host, smtpCfg.From)
	} else {
		log.Printf("smtp: host=%s from=%s to=%s", smtpCfg.Host, smtpCfg.From, smtpCfg.To)
	}

	go func() {
		for range time.Tick(24 * time.Hour) {
			if err := database.PruneExpiredSessions(); err != nil {
				log.Printf("prune sessions: %v", err)
			}
		}
	}()

	secureCookies := *secureCookiesFlag ||
		strings.EqualFold(os.Getenv("SECURE_COOKIES"), "true") ||
		os.Getenv("SECURE_COOKIES") == "1"

	addr := firstNonEmpty(*addrFlag, os.Getenv("ADDR"), cfg.Addr, ":8080")
	cookieURLs := map[string]string{
		"transfer": cfgOr(*transferHost, "TRANSFER_HOST", svc("transfer").URL),
		"notes":    cfgOr(*notesURL,     "NOTES_URL",     svc("notes").URL),
		"paste":    cfgOr(*pasteURL,     "PASTE_URL",     svc("paste").URL),
		"rss":      cfgOr(*rssURL,       "RSS_URL",       svc("rss").URL),
		"akkoma":   cfgOr(*akkomaURL, "AKKOMA_URL", svc("akkoma").URL),
		"pixelfed": cfgOr("", "PIXELFED_URL", svc("pixelfed").URL),
	}

	var oidcCfg *server.OIDCConfig
	if cfg.OIDC.Issuer != "" {
		oidcCfg = &server.OIDCConfig{Issuer: cfg.OIDC.Issuer, KeyFile: cfg.OIDC.KeyFile}
		for id, c := range cfg.OIDC.Clients {
			oidcCfg.Clients = append(oidcCfg.Clients, server.OIDCClient{
				ID: id, SecretSHA256: c.SecretSHA256, RedirectURIs: c.RedirectURIs,
				Service: c.Service, RequireEmail: c.RequireEmail,
			})
		}
		log.Printf("oidc: issuer=%s clients=%d", oidcCfg.Issuer, len(oidcCfg.Clients))
	}

	srv := server.New(database, svcURLs, svcDescs, smtpCfg, server.Config{
		SecureCookies:  secureCookies,
		InfoURLs:       infoURLs,
		CookieURLs:     cookieURLs,
		InternalSecret: firstNonEmpty(*internalSecret, os.Getenv("INTERNAL_SECRET"), cfg.InternalSecret),
		AuthSecret:     firstNonEmpty(*authSecret, os.Getenv("AUTH_SECRET"), cfg.AuthSecret),
		BaseDomain:     firstNonEmpty(*baseDomain, os.Getenv("BASE_DOMAIN"), cfg.BaseDomain),
		DefaultNote:    firstNonEmpty(*defaultNoteFlag, os.Getenv("DEFAULT_NOTE"), cfg.DefaultNote),
		OIDC:           oidcCfg,
		TOTPKeyFile:    firstNonEmpty(os.Getenv("TOTP_KEY_FILE"), cfg.TOTPKeyFile, filepath.Join(filepath.Dir(dbPath), "totp.key")),
		PublicURL:      firstNonEmpty(os.Getenv("PUBLIC_URL"), cfg.PublicURL, cfg.OIDC.Issuer),
	})
	// Docker stops us with SIGTERM: drain, then close the db so SQLite checkpoints and drops the WAL.
	ctx, stop := signal.NotifyContext(context.Background(), syscall.SIGTERM, os.Interrupt)
	defer stop()
	log.Printf("listening on %s", addr)
	err = srv.ListenAndServe(ctx, addr)
	if cerr := database.Close(); cerr != nil {
		log.Printf("close db: %v", cerr)
	}
	if err != nil {
		log.Fatal(err)
	}
	log.Print("stopped")
}

func firstNonEmpty(vals ...string) string {
	for _, v := range vals {
		if v != "" {
			return v
		}
	}
	return ""
}