package main

import (
	"sync"
	"time"

	"github.com/mattermost/mattermost/server/public/model"
	"github.com/mattermost/mattermost/server/public/plugin"
)

// Plugin implements the Mattermost plugin interface.
type Plugin struct {
	plugin.MattermostPlugin

	// configurationLock synchronizes access to the configuration.
	configurationLock sync.RWMutex

	// configuration is the active plugin configuration.
	configuration *Configuration

	// store wraps KV store operations for session persistence.
	store *Store

	// botUserIDLock synchronizes access to botUserID.
	botUserIDLock sync.RWMutex

	// botUserID is the plugin's bot user ID (created on activation).
	botUserID string

	// stopCleanup signals the cleanup goroutine to stop.
	stopCleanup chan struct{}
}

// OnActivate is called when the plugin is activated.
func (p *Plugin) OnActivate() error {
	p.store = NewStore(p.API)

	// Ensure plugin bot user exists
	botID, appErr := p.API.EnsureBotUser(&model.Bot{
		Username:    "livestatus",
		DisplayName: "Live Status",
		Description: "OpenClaw Live Status plugin bot",
	})
	if appErr != nil {
		p.API.LogWarn("Failed to ensure bot user", "error", appErr.Error())
	} else {
		p.botUserIDLock.Lock()
		p.botUserID = botID
		p.botUserIDLock.Unlock()
		p.API.LogInfo("Plugin bot user ensured", "botUserID", botID)
	}

	// Start session cleanup goroutine
	p.stopCleanup = make(chan struct{})
	go p.sessionCleanupLoop()

	p.API.LogInfo("OpenClaw Live Status plugin activated")
	return nil
}

// sessionCleanupLoop runs periodically to clean up stale and expired sessions.
func (p *Plugin) sessionCleanupLoop() {
	ticker := time.NewTicker(5 * time.Minute)
	defer ticker.Stop()

	for {
		select {
		case <-ticker.C:
			staleThreshold := int64(30 * 60 * 1000)  // 30 minutes — active sessions with no update
			expireThreshold := int64(60 * 60 * 1000)  // 1 hour — completed/interrupted sessions
			cleaned, expired, err := p.store.CleanStaleSessions(staleThreshold, expireThreshold)
			if err != nil {
				p.API.LogWarn("Session cleanup error", "error", err.Error())
			} else if cleaned > 0 || expired > 0 {
				p.API.LogInfo("Session cleanup completed", "stale_marked", cleaned, "expired_deleted", expired)
			}
		case <-p.stopCleanup:
			return
		}
	}
}

// getBotUserID returns the plugin's bot user ID (thread-safe).
func (p *Plugin) getBotUserID() string {
	p.botUserIDLock.RLock()
	defer p.botUserIDLock.RUnlock()
	return p.botUserID
}

// OnDeactivate is called when the plugin is deactivated.
func (p *Plugin) OnDeactivate() error {
	// Stop cleanup goroutine
	if p.stopCleanup != nil {
		close(p.stopCleanup)
	}

	// Mark all active sessions as interrupted
	sessions, err := p.store.ListAllSessions()
	if err != nil {
		p.API.LogWarn("Failed to list sessions on deactivate", "error", err.Error())
	} else {
		for _, s := range sessions {
			// Skip sessions already in a terminal state — do not overwrite done/error
			if s.Status == "done" || s.Status == "error" {
				continue
			}
			s.Status = "interrupted"
			_ = p.store.SaveSession(s.SessionKey, s)
			p.broadcastUpdate(s.ChannelID, s)
		}
	}

	p.API.LogInfo("OpenClaw Live Status plugin deactivated")
	return nil
}