package main

import (
	"sort"
	"time"

	"verstak/internal/core/activity"
	"verstak/internal/core/nodes"
	syncsvc "verstak/internal/core/sync"
	"verstak/internal/i18n"
)

type SystemViewDTO struct {
	ID    string `json:"id"`
	Label string `json:"label"`
}

func (a *App) ListSystemViews() []SystemViewDTO {
	return []SystemViewDTO{
		{ID: "today", Label: i18n.TF("ru", "nav.today")},
		{ID: "inbox", Label: i18n.TF("ru", "nav.inbox")},
		{ID: "activity", Label: i18n.TF("ru", "nav.activity")},
	}
}

func (a *App) ListTodayView() (*TodayDashboardDTO, error) {
	aeByParent, err := a.activity.ListTodayEventsByParent()
	if err != nil {
		aeByParent = nil
	}
	todayNodes, _ := a.nodes.ListTodayNodes()

	type rawEvent struct {
		NodeID     string
		EventType  string
		TargetType string
		TargetID   string
		TargetPath string
		Title      string
		CreatedAt  string
	}
	type caseInfo struct {
		Node   nodes.Node
		Events []rawEvent
	}
	caseMap := make(map[string]*caseInfo)

	ensureCase := func(caseID string) *caseInfo {
		if ci, ok := caseMap[caseID]; ok {
			return ci
		}
		ci := &caseInfo{Events: nil}
		if n, err := a.nodes.GetActive(caseID); err == nil {
			ci.Node = *n
		}
		caseMap[caseID] = ci
		return ci
	}

	for pid, events := range aeByParent {
		ci := ensureCase(pid)
		for _, e := range events {
			ci.Events = append(ci.Events, rawEvent{
				NodeID:     e.NodeID,
				EventType:  e.EventType,
				TargetType: e.TargetType,
				TargetID:   e.TargetID,
				TargetPath: e.TargetPath,
				Title:      e.Title,
				CreatedAt:  e.CreatedAt,
			})
		}
	}

	for _, n := range todayNodes {
		_ = ensureCase(n.ID)
		if ci := caseMap[n.ID]; ci.Node.ID == "" {
			ci.Node = n
		}
	}

	var groups []TodayGroupDTO
	var flatEvents []EventDTO
	summary := SummaryDTO{}

	for _, ci := range caseMap {
		if ci.Node.ID == "" {
			continue
		}
		summary.ChangedCases++

		dtoEvents := make([]EventDTO, 0, len(ci.Events))
		for _, re := range ci.Events {
			dtoEvents = append(dtoEvents, EventDTO{
				ID:         ci.Node.ID + "/" + re.NodeID + "/" + re.CreatedAt,
				NodeID:     re.NodeID,
				EventType:  re.EventType,
				TargetType: re.TargetType,
				TargetID:   re.TargetID,
				TargetPath: re.TargetPath,
				Title:      re.Title,
				CreatedAt:  re.CreatedAt,
			})
			switch re.EventType {
			case activity.TypeNoteCreated, activity.TypeNoteUpdated:
				summary.Notes++
			case activity.TypeFileAdded, activity.TypeFileDeleted, activity.TypeFileRenamed, activity.TypeFileCopied, activity.TypeFileMoved:
				summary.Files++
			}
		}

		last := ci.Node.UpdatedAt.Format(time.RFC3339)
		for _, e := range dtoEvents {
			if e.CreatedAt > last {
				last = e.CreatedAt
			}
		}

		groups = append(groups, TodayGroupDTO{
			NodeID:         ci.Node.ID,
			NodeTitle:      ci.Node.Title,
			NodeKind:       ci.Node.Type,
			Section:        ci.Node.Section,
			LastActivityAt: last,
			Events:         dtoEvents,
		})
		flatEvents = append(flatEvents, dtoEvents...)
	}

	sort.Slice(groups, func(i, j int) bool {
		return groups[i].LastActivityAt > groups[j].LastActivityAt
	})
	sort.Slice(flatEvents, func(i, j int) bool {
		return flatEvents[i].CreatedAt > flatEvents[j].CreatedAt
	})

	return &TodayDashboardDTO{
		Date:    time.Now().Format("2006-01-02"),
		Summary: summary,
		Groups:  groups,
		Events:  flatEvents,
	}, nil
}

func (a *App) ListActivityFeed(limit, offset int) ([]EventDTO, error) {
	events, err := a.activity.ListRecent(limit, offset)
	if err != nil {
		return nil, err
	}
	result := make([]EventDTO, len(events))
	for i, e := range events {
		result[i] = toEventDTO(e)
	}
	return result, nil
}

func (a *App) ListActivityByNode(nodeID string, limit, offset int) ([]EventDTO, error) {
	events, err := a.activity.ListByNode(nodeID, limit, offset)
	if err != nil {
		return nil, err
	}
	result := make([]EventDTO, len(events))
	for i, e := range events {
		result[i] = toEventDTO(e)
	}
	return result, nil
}

func (a *App) CountActivityByNode(nodeID string) (int, error) {
	return a.activity.CountByNode(nodeID)
}

var _ = syncsvc.EntityNode