package tui

import (
	"context"
	"fmt"
	"strings"
	"sync"

	tea "github.com/charmbracelet/bubbletea"

	"git.tukangketik.id/swanadiva/hostkeeper/internal/models"
	"git.tukangketik.id/swanadiva/hostkeeper/pkg/storage"
)

type snippetListState int

const (
	snippetListLoading snippetListState = iota
	snippetListReady
	snippetListError
)

// SnippetListTab displays and manages command snippets
type SnippetListTab struct {
	dataDir  string
	snippets []*models.Snippet
	selected int
	state    snippetListState
	err      error
	width    int
	height   int
	mu       sync.Mutex
}

func NewSnippetListTab(dataDir string) *SnippetListTab {
	return &SnippetListTab{
		dataDir: dataDir,
		state:   snippetListLoading,
	}
}

func (t *SnippetListTab) Name() string { return "Snippets" }

func (t *SnippetListTab) Init() tea.Cmd {
	return func() tea.Msg {
		store, err := storage.NewJSONStorage(t.dataDir)
		if err != nil {
			return snippetListLoadedMsg{err: err}
		}
		snippets, err := store.ListSnippets(context.Background())
		if err != nil {
			return snippetListLoadedMsg{err: err}
		}
		return snippetListLoadedMsg{snippets: snippets}
	}
}

func (t *SnippetListTab) Update(msg tea.Msg) (Tab, tea.Cmd) {
	switch msg := msg.(type) {
	case tea.WindowSizeMsg:
		t.mu.Lock()
		t.width = msg.Width
		t.height = msg.Height
		t.mu.Unlock()

	case snippetListLoadedMsg:
		t.mu.Lock()
		if msg.err != nil {
			t.state = snippetListError
			t.err = msg.err
		} else {
			t.state = snippetListReady
			t.snippets = msg.snippets
		}
		t.mu.Unlock()

	case saveSnippetResultMsg:
		return t, t.Init()

	case deleteSnippetResultMsg:
		if msg.err != nil {
			t.mu.Lock()
			t.err = msg.err
			t.mu.Unlock()
		}
		return t, t.Init()

	case tea.KeyMsg:
		switch msg.String() {
		case "up", "k":
			t.mu.Lock()
			if t.selected > 0 {
				t.selected--
			}
			t.mu.Unlock()

		case "down", "j":
			t.mu.Lock()
			if t.selected < len(t.snippets)-1 {
				t.selected++
			}
			t.mu.Unlock()

		case "ctrl+n":
			return t, func() tea.Msg { return openSnippetFormMsg{} }

		case "ctrl+e":
			t.mu.Lock()
			snippets := t.snippets
			idx := t.selected
			t.mu.Unlock()
			if len(snippets) > 0 && idx >= 0 && idx < len(snippets) {
				return t, func() tea.Msg { return openSnippetFormMsg{editing: snippets[idx]} }
			}

		case "delete", "d":
			t.mu.Lock()
			snippets := t.snippets
			idx := t.selected
			t.mu.Unlock()
			if len(snippets) > 0 && idx >= 0 && idx < len(snippets) {
				return t, deleteSnippetCmd(snippets[idx].ID, t.dataDir)
			}

		case "esc":
			return t, func() tea.Msg { return closeFormMsg{} }
		}
	}

	return t, nil
}

func (t *SnippetListTab) View() string {
	t.mu.Lock()
	defer t.mu.Unlock()

	var b strings.Builder

	b.WriteString(AppTitleStyle.Render("Command Snippets"))
	b.WriteString("\n\n")

	switch t.state {
	case snippetListLoading:
		b.WriteString(SubtitleStyle.Render("Loading snippets..."))
		return b.String()
	case snippetListError:
		b.WriteString(ErrorStyle.Render(fmt.Sprintf("Error: %v", t.err)))
		b.WriteString("\n\n")
		b.WriteString(SubtitleStyle.Render("Press Esc to go back"))
		return b.String()
	}

	if t.err != nil {
		b.WriteString(ErrorStyle.Render(fmt.Sprintf("Error: %v", t.err)))
		b.WriteString("\n\n")
	}

	if len(t.snippets) == 0 {
		b.WriteString(SubtitleStyle.Render("No snippets stored."))
		b.WriteString("\n")
		b.WriteString(SubtitleStyle.Render("Press Ctrl+N to add a new snippet."))
	} else {
		for i, sn := range t.snippets {
			var line string
			desc := sn.Description
			if desc != "" {
				line = fmt.Sprintf("  %s  — %s", sn.Name, desc)
			} else {
				line = fmt.Sprintf("  %s", sn.Name)
			}

			if i == t.selected {
				b.WriteString(SelectedStyle.Render(line))
			} else {
				b.WriteString(HostNameStyle.Render(line))
			}
			b.WriteString("\n")
		}
	}

	b.WriteString("\n")
	b.WriteString(SubtitleStyle.Render("Ctrl+N:add  Ctrl+E:edit  D:delete  Esc:back"))

	return b.String()
}

func (t *SnippetListTab) Close() {}

// snippetListLoadedMsg carries the loaded snippet list
type snippetListLoadedMsg struct {
	snippets []*models.Snippet
	err      error
}