package main

import (
	"encoding/json"
	"errors"
	"flag"
	"fmt"
	"log"
	"os"
	"time"

	"github.com/descrybe/descrybe-v2/apps/api/internal/config"
	"github.com/descrybe/descrybe-v2/apps/api/internal/mail"
	"github.com/google/uuid"
)

// Hook matches migrator maps/set-password-hooks.json (invite tokens for must_set_password users).
type Hook struct {
	UserID    uuid.UUID `json:"user_id"`
	Email     string    `json:"email"`
	CompanyID uuid.UUID `json:"company_id"`
	Role      string    `json:"role"`
	Token     string    `json:"token"`
	ExpiresAt time.Time `json:"expires_at"`
	InviteID  uuid.UUID `json:"invite_id"`
}

func main() {
	hooksPath := flag.String("hooks", "", "Path to set-password-hooks.json from migrator maps-dir")
	dryRun := flag.Bool("dry-run", false, "Print counts without sending")
	delayMS := flag.Int("delay-ms", 100, "Pause between sends (SMTP rate limit)")
	flag.Parse()

	if *hooksPath == "" {
		log.Fatal("-hooks is required (e.g. ../../artifacts/maps/set-password-hooks.json)")
	}

	cfg, err := config.Load()
	if err != nil {
		log.Fatalf("config: %v", err)
	}

	raw, err := os.ReadFile(*hooksPath)
	if err != nil {
		log.Fatalf("read hooks: %v", err)
	}
	var hooks []Hook
	if err := json.Unmarshal(raw, &hooks); err != nil {
		log.Fatalf("parse hooks: %v", err)
	}

	mailer := mail.New(mail.Config{
		Enabled:  cfg.SMTPEnabled,
		Host:     cfg.SMTPHost,
		Port:     cfg.SMTPPort,
		User:     cfg.SMTPUser,
		Password: cfg.SMTPPassword,
		From:     cfg.SMTPFrom,
	})
	if err := assertMailhooksReady(*dryRun, mailer.Enabled(), cfg.EmailDryRun); err != nil {
		log.Fatal(err)
	}

	sent, skipped, failed := 0, 0, 0
	now := time.Now().UTC()
	for _, h := range hooks {
		if h.Token == "" || h.Email == "" {
			skipped++
			continue
		}
		if !h.ExpiresAt.IsZero() && now.After(h.ExpiresAt) {
			skipped++
			continue
		}
		msg := mail.MigratedSetPasswordMessage(cfg.WebOrigin, h.Email, h.Token)
		if *dryRun {
			log.Printf("mailhooks: dry-run subject=%q", msg.Subject)
			sent++
			continue
		}
		if err := mailer.Send(msg); err != nil {
			log.Printf("mailhooks: send failed subject=%q", msg.Subject)
			failed++
			continue
		}
		sent++
		if *delayMS > 0 {
			time.Sleep(time.Duration(*delayMS) * time.Millisecond)
		}
	}

	fmt.Printf("mailhooks: sent=%d skipped=%d failed=%d smtp_enabled=%v total=%d\n",
		sent, skipped, failed, mailer.Enabled(), len(hooks))
	if failed > 0 {
		os.Exit(1)
	}
}

// assertMailhooksReady fails closed for live sends when SMTP is a no-op or EMAIL_DRY_RUN is on.
func assertMailhooksReady(dryRun, mailerEnabled, emailDryRun bool) error {
	if dryRun {
		return nil
	}
	if emailDryRun {
		return errors.New("mailhooks: email dry-run is on; pass -dry-run or disable dry-run in admin platform mail settings (or EMAIL_DRY_RUN=false)")
	}
	if !mailerEnabled {
		return errors.New("mailhooks: SMTP not configured; pass -dry-run or set platform mail SMTP in admin (smtp.enabled + host/from)")
	}
	return nil
}