// Package bot implements the Telegram bot interface for KeyHunter.
// It wraps existing scan, verify, recon, and storage functionality,
// exposing them through Telegram command handlers via the telego library.
package bot

import (
	"context"
	"fmt"
	"sync"
	"time"

	"github.com/mymmrac/telego"
	th "github.com/mymmrac/telego/telegohandler"

	"github.com/salvacybersec/keyhunter/pkg/engine"
	"github.com/salvacybersec/keyhunter/pkg/providers"
	"github.com/salvacybersec/keyhunter/pkg/recon"
	"github.com/salvacybersec/keyhunter/pkg/storage"
	"github.com/salvacybersec/keyhunter/pkg/verify"
)

// Bot holds the Telegram bot instance and all dependencies needed
// to process commands. It delegates to the existing KeyHunter engine,
// verifier, recon engine, and storage layer.
type Bot struct {
	api      *telego.Bot
	handler  *th.BotHandler
	engine   *engine.Engine
	verifier *verify.HTTPVerifier
	recon    *recon.Engine
	db       *storage.DB
	registry *providers.Registry
	encKey   []byte

	mu        sync.Mutex
	startedAt time.Time
	lastScan  time.Time
}

// Deps bundles the dependencies required to construct a Bot.
type Deps struct {
	Engine   *engine.Engine
	Verifier *verify.HTTPVerifier
	Recon    *recon.Engine
	DB       *storage.DB
	Registry *providers.Registry
	EncKey   []byte
}

// New creates a Bot backed by the given telego API client and dependencies.
// Call RegisterHandlers to wire up command handlers before starting the update loop.
func New(api *telego.Bot, deps Deps) *Bot {
	return &Bot{
		api:       api,
		engine:    deps.Engine,
		verifier:  deps.Verifier,
		recon:     deps.Recon,
		db:        deps.DB,
		registry:  deps.Registry,
		encKey:    deps.EncKey,
		startedAt: time.Now(),
	}
}

// RegisterHandlers wires all command handlers into a BotHandler that processes
// updates from the Telegram API. The caller must call Start() on the returned
// BotHandler to begin processing.
func (b *Bot) RegisterHandlers(updates <-chan telego.Update) *th.BotHandler {
	bh, _ := th.NewBotHandler(b.api, updates)

	bh.HandleMessage(b.handleHelp, th.CommandEqual("help"))
	bh.HandleMessage(b.handleScan, th.CommandEqual("scan"))
	bh.HandleMessage(b.handleVerify, th.CommandEqual("verify"))
	bh.HandleMessage(b.handleRecon, th.CommandEqual("recon"))
	bh.HandleMessage(b.handleStatus, th.CommandEqual("status"))
	bh.HandleMessage(b.handleStats, th.CommandEqual("stats"))
	bh.HandleMessage(b.handleProviders, th.CommandEqual("providers"))
	bh.HandleMessage(b.handleKey, th.CommandEqual("key"))

	b.handler = bh
	return bh
}

// reply sends a text message back to the chat that originated msg.
func (b *Bot) reply(ctx context.Context, msg *telego.Message, text string) {
	_, _ = b.api.SendMessage(ctx, &telego.SendMessageParams{
		ChatID: telego.ChatID{ID: msg.Chat.ID},
		Text:   text,
	})
}

// isPrivateChat returns true if the message was sent in a private (1:1) chat.
func isPrivateChat(msg *telego.Message) bool {
	return msg.Chat.Type == "private"
}

// runScan executes a scan against the given path and returns findings.
// Findings are collected synchronously; the caller formats the output.
func (b *Bot) runScan(ctx context.Context, path string) ([]engine.Finding, error) {
	src, err := selectBotSource(path)
	if err != nil {
		return nil, err
	}

	cfg := engine.ScanConfig{
		Workers: 0, // auto
		Verify:  false,
		Unmask:  false,
	}

	ch, err := b.engine.Scan(ctx, src, cfg)
	if err != nil {
		return nil, fmt.Errorf("starting scan: %w", err)
	}

	var findings []engine.Finding
	for f := range ch {
		findings = append(findings, f)
	}

	// Persist findings
	for _, f := range findings {
		sf := storage.Finding{
			ProviderName: f.ProviderName,
			KeyValue:     f.KeyValue,
			KeyMasked:    f.KeyMasked,
			Confidence:   f.Confidence,
			SourcePath:   f.Source,
			SourceType:   f.SourceType,
			LineNumber:   f.LineNumber,
		}
		_, _ = b.db.SaveFinding(sf, b.encKey)
	}

	b.mu.Lock()
	b.lastScan = time.Now()
	b.mu.Unlock()

	return findings, nil
}