// Package jailmgr talks to jail(8) directly via jail.conf.d and the base
// system's `service jail` rc.d script - no bastille/iocage in the loop.
package jailmgr

import (
	"context"
	"fmt"
	"io"
	"os"
	"path/filepath"

	"skiff/internal/layout"
	"skiff/internal/sh"
	"skiff/internal/tmpl"
)

// WriteConf renders jail.conf.d/<app>.conf and the jail's own rc.d service
// script + rc.conf enable line. Called once, from `skiff new-app`.
func WriteConf(cfg layout.Config, app, ip, iface string) error {
	conf, err := tmpl.JailConf(tmpl.JailConfData{Name: app, JailRoot: cfg.JailRoot(app), IP: ip, Iface: iface})
	if err != nil {
		return err
	}
	if err := os.WriteFile(cfg.JailConfPath(app), []byte(conf), 0644); err != nil {
		return fmt.Errorf("write jail.conf: %w", err)
	}

	rc, err := tmpl.RCScript(tmpl.RCData{Name: app})
	if err != nil {
		return err
	}
	rcPath := cfg.RCScriptPath(app)
	if err := os.MkdirAll(filepath.Dir(rcPath), 0755); err != nil {
		return err
	}
	if err := os.WriteFile(rcPath, []byte(rc), 0755); err != nil {
		return fmt.Errorf("write rc.d script: %w", err)
	}

	rcConfLine := fmt.Sprintf("\n%s_enable=\"YES\"\n", app)
	f, err := os.OpenFile(cfg.RCConfPath(app), os.O_APPEND|os.O_CREATE|os.O_WRONLY, 0644)
	if err != nil {
		return fmt.Errorf("open jail rc.conf: %w", err)
	}
	defer f.Close()
	if _, err := f.WriteString(rcConfLine); err != nil {
		return fmt.Errorf("enable service in jail rc.conf: %w", err)
	}
	return nil
}

// EnableMail appends a MAILNAME line to the jail's dma.conf, inherited from
// the base image's SMARTHOST/PORT/AUTHPATH/SECURETRANSFER/STARTTLS. Called
// once, from `skiff new-app`.
func EnableMail(cfg layout.Config, app string) error {
	f, err := os.OpenFile(cfg.DMAConfPath(app), os.O_APPEND|os.O_CREATE|os.O_WRONLY, 0644)
	if err != nil {
		return fmt.Errorf("open jail dma.conf: %w", err)
	}
	defer f.Close()
	if _, err := fmt.Fprintf(f, "\nMAILNAME %s.skiff.local\n", app); err != nil {
		return fmt.Errorf("set MAILNAME in jail dma.conf: %w", err)
	}
	return nil
}

func Start(ctx context.Context, out io.Writer, app string) error {
	return sh.Run(ctx, out, "", "service", "jail", "start", app)
}

// Restart restarts an already-running jail, or starts it if this is its
// first deploy and it isn't up yet.
func Restart(ctx context.Context, out io.Writer, app string) error {
	if err := sh.Run(ctx, out, "", "service", "jail", "restart", app); err != nil {
		return sh.Run(ctx, out, "", "service", "jail", "start", app)
	}
	return nil
}