package main

import (
	"context"
	"fmt"
	"os"
	"os/exec"
	"path/filepath"
	"strings"

	wailsruntime "github.com/wailsapp/wails/v2/pkg/runtime"

	"verstak/internal/core/actions"
	"verstak/internal/core/files"
	"verstak/internal/core/notes"
	"verstak/internal/core/nodes"
	"verstak/internal/core/search"
	"verstak/internal/core/storage"
	"verstak/internal/core/worklog"
)



// App is the Wails v2 application adapter. It wraps core services.
type App struct {
	ctx     context.Context
	db      *storage.DB
	nodes   *nodes.Repository
	files   *files.Service
	notes   *notes.Service
	actions *actions.Service
	worklog *worklog.Service
	search  *search.Service
	vault   string
}

// startup is called when the app starts. Store context and wire drag-and-drop.
func (a *App) startup(ctx context.Context) {
	a.ctx = ctx
	wailsruntime.OnFileDrop(ctx, func(x, y int, paths []string) {
		if len(paths) > 0 {
			wailsruntime.EventsEmit(ctx, "files-dropped", paths)
		}
	})
}

// ============================================================
// DTOs
// ============================================================

type NodeDTO struct {
	ID        string `json:"id"`
	ParentID  string `json:"parentId"`
	Title     string `json:"title"`
	Type      string `json:"type"`
	Section   string `json:"section"`
	Path      string `json:"path"`
	CreatedAt string `json:"createdAt"`
}

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

type NoteDTO struct {
	ID        string `json:"id"`
	Title     string `json:"title"`
	Content   string `json:"content"`
	Format    string `json:"format"`
	CreatedAt string `json:"createdAt"`
}

type FileDTO struct {
	ID       string `json:"id"`
	NodeID   string `json:"nodeId"`
	Name     string `json:"name"`
	Path     string `json:"path"`
	Size     int64  `json:"size"`
	Mime     string `json:"mime"`
	IsDir    bool   `json:"isDir"`
	Missing  bool   `json:"missing"`
}

type FileTreeItemDTO struct {
	ID     string `json:"id"`
	Name   string `json:"name"`
	Type   string `json:"type"` // "folder" | "file"
	FileID string `json:"fileId,omitempty"`
	Size   int64  `json:"size,omitempty"`
	Mime   string `json:"mime,omitempty"`
	HasKids bool  `json:"hasKids"`
}

type ActionDTO struct {
	ID     string `json:"id"`
	NodeID string `json:"nodeId"`
	Title  string `json:"title"`
	Type   string `json:"type"`
	Data   string `json:"data"`
}

type WorklogDTO struct {
	ID        string `json:"id"`
	NodeID    string `json:"nodeId"`
	Summary   string `json:"summary"`
	Minutes   int    `json:"minutes"`
	CreatedAt string `json:"createdAt"`
}

type SearchResultDTO struct {
	NodeID  string `json:"nodeId"`
	Title   string `json:"title"`
	Snippet string `json:"snippet"`
	Type    string `json:"type"`
}

// ============================================================
// Sections
// ============================================================

func (a *App) ListSections() []SectionDTO {
	return []SectionDTO{
		{ID: "today", Label: "Сегодня"},
		{ID: "inbox", Label: "Неразобранное"},
		{ID: "clients", Label: "Клиенты"},
		{ID: "projects", Label: "Проекты"},
		{ID: "recipes", Label: "Рецепты"},
		{ID: "documents", Label: "Документы"},
		{ID: "archive", Label: "Архив"},
	}
}

// ============================================================
// Nodes
// ============================================================

func (a *App) ListNodesBySection(section string) ([]NodeDTO, error) {
	list, err := a.nodes.ListRoots(false, section)
	if err != nil {
		return nil, err
	}
	return toNodeDTOs(list), nil
}

// ListTodayView returns nodes created or updated today — a dynamic day view.
func (a *App) ListTodayView() ([]NodeDTO, error) {
	list, err := a.nodes.ListTodayNodes()
	if err != nil {
		return nil, err
	}
	return toNodeDTOs(list), nil
}

func (a *App) ListChildren(parentID string) ([]NodeDTO, error) {
	list, err := a.nodes.ListChildren(parentID, false)
	if err != nil {
		return nil, err
	}
	return toNodeDTOs(list), nil
}

func (a *App) GetNodeDetail(nodeID string) (*NodeDTO, error) {
	n, err := a.nodes.GetActive(nodeID)
	if err != nil {
		return nil, err
	}
	dto := toNodeDTO(n)
	return &dto, nil
}

func (a *App) CreateNode(parentID, nodeType, title, section string) (*NodeDTO, error) {
	if section == "today" || section == "inbox" {
		return nil, fmt.Errorf("cannot create node with section %q", section)
	}
	n, err := a.nodes.Create(parentID, nodeType, title, section)
	if err != nil {
		return nil, err
	}
	dto := toNodeDTO(n)
	return &dto, nil
}

func (a *App) DeleteNode(id string) error {
	return a.nodes.SoftDelete(id)
}

// ============================================================
// Notes
// ============================================================

// ListNotes returns note-type children of a node.
func (a *App) ListNotes(nodeID string) ([]NodeDTO, error) {
	children, err := a.nodes.ListChildren(nodeID, false)
	if err != nil {
		return nil, err
	}
	var result []NodeDTO
	for i := range children {
		if children[i].Type == nodes.TypeNote {
			result = append(result, toNodeDTO(&children[i]))
		}
	}
	return result, nil
}

// CreateNote creates a note under a parent node.
func (a *App) CreateNote(parentID, title string) (*NodeDTO, error) {
	node, _, err := a.notes.Create(parentID, title, "")
	if err != nil {
		return nil, err
	}
	dto := toNodeDTO(node)
	return &dto, nil
}

// ReadNote reads note content.
func (a *App) ReadNote(noteID string) (string, error) {
	return a.notes.Read(noteID)
}

// SaveNote saves note content.
func (a *App) SaveNote(noteID, content string) error {
	return a.notes.Save(noteID, content)
}

// ============================================================
// Files
// ============================================================

// ListFiles returns file records directly linked to a node (non-recursive).
func (a *App) ListFiles(nodeID string) ([]FileDTO, error) {
	records, err := a.files.ListByNode(nodeID)
	if err != nil {
		return nil, err
	}
	result := make([]FileDTO, len(records))
	for i := range records {
		rec := &records[i]
		result[i] = FileDTO{
			ID:      rec.ID,
			NodeID:  rec.NodeID,
			Name:    rec.Filename,
			Path:    rec.Path,
			Size:    rec.Size,
			Mime:    rec.MIME,
			IsDir:   rec.MIME == "inode/directory",
			Missing: rec.Missing,
		}
	}
	return result, nil
}

// ListItems returns children of a node for the file tree view.
// Folders can be expanded; files include their file record info.
func (a *App) ListItems(nodeID string) ([]FileTreeItemDTO, error) {
	children, err := a.nodes.ListChildren(nodeID, false)
	if err != nil {
		return nil, err
	}
	result := make([]FileTreeItemDTO, 0, len(children))
	for i := range children {
		if children[i].Type != nodes.TypeFolder && children[i].Type != nodes.TypeFile {
			continue
		}
		item := FileTreeItemDTO{
			ID:   children[i].ID,
			Name: children[i].Title,
			Type: children[i].Type,
		}
		if children[i].Type == nodes.TypeFolder {
			// Check if this folder has children
			kids, _ := a.nodes.ListChildren(children[i].ID, false)
			item.HasKids = len(kids) > 0
		} else if children[i].Type == nodes.TypeFile {
			records, _ := a.files.ListByNode(children[i].ID)
			if len(records) > 0 {
				item.FileID = records[0].ID
				item.Size = records[0].Size
				item.Mime = records[0].MIME
			}
		}
		result = append(result, item)
	}
	return result, nil
}

func (a *App) AddPathCopy(nodeID, sourcePath string) ([]NodeDTO, error) {
	nodes, err := a.files.AddPathCopy(nodeID, sourcePath)
	if err != nil {
		return nil, err
	}
	return toNodeDTOs(nodes), nil
}

func (a *App) AddPathLink(nodeID, sourcePath string) ([]NodeDTO, error) {
	nodes, err := a.files.AddPathLink(nodeID, sourcePath)
	if err != nil {
		return nil, err
	}
	return toNodeDTOs(nodes), nil
}

func (a *App) DeleteFileOrFolder(nodeID string) error {
	return a.files.DeleteNodeAndChildren(nodeID)
}

func (a *App) CreateEmptyFile(parentID, filename string) (*NodeDTO, error) {
	node, err := a.files.CreateEmptyFile(parentID, filename)
	if err != nil {
		return nil, err
	}
	dto := toNodeDTO(node)
	return &dto, nil
}

func (a *App) DuplicateNode(nodeID string) (*NodeDTO, error) {
	node, err := a.files.Duplicate(nodeID)
	if err != nil {
		return nil, err
	}
	dto := toNodeDTO(node)
	return &dto, nil
}

func (a *App) RenameNode(nodeID, newTitle string) error {
	return a.nodes.UpdateTitle(nodeID, newTitle)
}

func (a *App) ValidateName(name string) error {
	return files.ValidateName(name)
}

func (a *App) MoveNode(nodeID, newParentID string) error {
	// Check for name conflict at destination
	destChildren, err := a.nodes.ListChildren(newParentID, false)
	if err != nil {
		return err
	}
	node, err := a.nodes.GetActive(nodeID)
	if err != nil {
		return err
	}
	for i := range destChildren {
		if destChildren[i].Title == node.Title {
			// Conflict: auto-rename
			newName := a.files.UniqueTitleCopy(newParentID, node.Title)
			if err := a.nodes.UpdateTitle(nodeID, newName); err != nil {
				return err
			}
			break
		}
	}
	return a.nodes.Move(nodeID, newParentID, 0)
}

func (a *App) PreviewImport(sourcePath string) (*files.ImportSummary, error) {
	return a.files.PreviewImport(sourcePath)
}

// ============================================================
// Actions
// ============================================================

func (a *App) ListActions(nodeID string) ([]ActionDTO, error) {
	list, err := a.actions.ListByNode(nodeID)
	if err != nil {
		return nil, err
	}
	result := make([]ActionDTO, len(list))
	for i := range list {
		data := list[i].Command
		if list[i].URL != "" {
			data = list[i].URL
		}
		result[i] = ActionDTO{
			ID:     list[i].ID,
			NodeID: list[i].NodeID,
			Title:  list[i].Title,
			Type:   list[i].Kind,
			Data:   data,
		}
	}
	return result, nil
}

func (a *App) RunAction(id string) error {
	_, err := a.actions.Run(id)
	return err
}

// ============================================================
// Worklog
// ============================================================

func (a *App) ListWorklog(nodeID string) ([]WorklogDTO, error) {
	list, err := a.worklog.ListByNode(nodeID)
	if err != nil {
		return nil, err
	}
	result := make([]WorklogDTO, len(list))
	for i := range list {
		mins := 0
		if list[i].Minutes != nil {
			mins = *list[i].Minutes
		}
		result[i] = WorklogDTO{
			ID:        list[i].ID,
			NodeID:    list[i].NodeID,
			Summary:   list[i].Summary,
			Minutes:   mins,
			CreatedAt: list[i].CreatedAt.Format("2006-01-02T15:04:05Z"),
		}
	}
	return result, nil
}

func (a *App) CreateWorklog(nodeID, summary string, minutes int) (*WorklogDTO, error) {
	entry, err := a.worklog.Add(nodeID, summary, "", minutes, false, false)
	if err != nil {
		return nil, err
	}
	mins := 0
	if entry.Minutes != nil {
		mins = *entry.Minutes
	}
	dto := &WorklogDTO{
		ID:        entry.ID,
		NodeID:    entry.NodeID,
		Summary:   entry.Summary,
		Minutes:   mins,
		CreatedAt: entry.CreatedAt.Format("2006-01-02T15:04:05Z"),
	}
	return dto, nil
}

// ============================================================
// Search
// ============================================================

func (a *App) Search(query string) ([]SearchResultDTO, error) {
	if strings.TrimSpace(query) == "" {
		return []SearchResultDTO{}, nil
	}
	results, err := a.search.Search(query)
	if err != nil {
		return nil, err
	}
	out := make([]SearchResultDTO, len(results))
	for i, r := range results {
		out[i] = SearchResultDTO{
			NodeID:  r.NodeID,
			Title:   r.Title,
			Snippet: r.Snippet,
			Type:    r.Type,
		}
	}
	return out, nil
}

// ============================================================
// File Dialogs (Wails v2 Runtime)
// ============================================================

func (a *App) PickFile() (string, error) {
	return wailsruntime.OpenFileDialog(a.ctx, wailsruntime.OpenDialogOptions{
		Title: "Выберите файл",
	})
}

func (a *App) PickFiles() ([]string, error) {
	return wailsruntime.OpenMultipleFilesDialog(a.ctx, wailsruntime.OpenDialogOptions{
		Title: "Выберите файлы",
	})
}

func (a *App) PickDirectory() (string, error) {
	return wailsruntime.OpenDirectoryDialog(a.ctx, wailsruntime.OpenDialogOptions{
		Title: "Выберите папку",
	})
}

// ============================================================
// System helpers
// ============================================================

func (a *App) OpenFile(fileID string) error {
	return a.files.Open(fileID)
}

func (a *App) ReadFileText(fileID string) (string, error) {
	return a.files.ReadText(fileID)
}

func (a *App) GetFileBase64(fileID string) (string, error) {
	return a.files.ReadBase64(fileID)
}

func (a *App) OpenFolder(nodeID string) error {
	n, err := a.nodes.GetActive(nodeID)
	if err != nil {
		return fmt.Errorf("get node: %w", err)
	}
	dir := filepath.Join(a.vault, "spaces", n.Slug)
	if _, err := os.Stat(dir); os.IsNotExist(err) {
		dir = a.vault
	}
	cmd := exec.Command("xdg-open", dir)
	return cmd.Run()
}

func (a *App) VerstakVersion() string {
	return "verstak-gui/v2"
}

// ============================================================
// Helpers
// ============================================================

func toNodeDTO(n *nodes.Node) NodeDTO {
	parentID := ""
	if n.ParentID != nil {
		parentID = *n.ParentID
	}
	path := ""
	if n.Path != nil {
		path = *n.Path
	}
	return NodeDTO{
		ID:        n.ID,
		ParentID:  parentID,
		Title:     n.Title,
		Type:      n.Type,
		Section:   n.Section,
		Path:      path,
		CreatedAt: n.CreatedAt.Format("2006-01-02T15:04:05Z"),
	}
}

func toNodeDTOs(list []nodes.Node) []NodeDTO {
	result := make([]NodeDTO, len(list))
	for i := range list {
		result[i] = toNodeDTO(&list[i])
	}
	return result
}