package tui

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

	tea "github.com/charmbracelet/bubbletea"
	"github.com/charmbracelet/lipgloss"

	"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()

	if t.state == snippetListLoading {
		return lipgloss.PlaceHorizontal(t.width, lipgloss.Center,
			SubtitleStyle.Render("Loading snippets..."))
	}
	if t.state == snippetListError {
		var b strings.Builder
		b.WriteString(lipgloss.PlaceHorizontal(t.width, lipgloss.Center,
			ErrorStyle.Render(fmt.Sprintf("Error: %v", t.err))))
		b.WriteString("\n")
		b.WriteString(lipgloss.PlaceHorizontal(t.width, lipgloss.Center,
			SubtitleStyle.Render("Press Esc to go back")))
		return b.String()
	}

	type styledRow struct {
		text  string
		plain string
	}

	titlePlain := "Command Snippets"

	var rows []styledRow
	if t.err != nil {
		errLine := fmt.Sprintf("Error: %v", t.err)
		rows = append(rows, styledRow{text: ErrorStyle.Render(errLine), plain: errLine})
	}

	if len(t.snippets) == 0 {
		empty := "No snippets stored."
		hint := "Press Ctrl+N to add a new snippet."
		rows = append(rows, styledRow{text: SubtitleStyle.Render(empty), plain: empty})
		rows = append(rows, styledRow{text: SubtitleStyle.Render(hint), plain: hint})
	} else {
		for i, sn := range t.snippets {
			var plain string
			if sn.Description != "" {
				plain = fmt.Sprintf("  %s  — %s", sn.Name, sn.Description)
			} else {
				plain = fmt.Sprintf("  %s", sn.Name)
			}
			var styled string
			if i == t.selected {
				styled = lipgloss.NewStyle().
					Foreground(gbFg).
					Background(gbBgSel).
					Bold(true).
					Render("▸ " + strings.TrimLeft(plain, " "))
			} else {
				styled = lipgloss.NewStyle().Foreground(gbFg).Render(plain)
			}
			rows = append(rows, styledRow{text: styled, plain: plain})
		}
	}

	// Responsive width
	sidePad := adaptiveSidePad(t.width)
	widestContent := lipgloss.Width(titlePlain)
	for _, r := range rows {
		if w := lipgloss.Width(r.plain); w > widestContent {
			widestContent = w
		}
	}
	targetW := clampWidth(widestContent+sidePad*2, t.width)
	innerW := targetW - sidePad*2
	if innerW < 1 {
		innerW = 1
	}

	// Footer (wrapped)
	footerText := "Ctrl+Tab:switch  Ctrl+Q:close  ↑↓:nav  Ctrl+N:add  Ctrl+E:edit  D:delete  Esc:back"
	footerWrapped := wrapFooter(footerText, innerW)

	// Render
	var inner strings.Builder
	titleStyled := lipgloss.NewStyle().Bold(true).Foreground(gbYellow).Render(titlePlain)
	inner.WriteString(lipgloss.PlaceHorizontal(targetW, lipgloss.Center, titleStyled))
	inner.WriteString("\n\n")

	for _, r := range rows {
		styled := r.text
		if lipgloss.Width(r.plain) > innerW {
			styled = truncateStr(r.text, innerW)
		}
		line := lipgloss.PlaceHorizontal(targetW, lipgloss.Center, styled)
		inner.WriteString(line)
		inner.WriteString("\n")
	}
	inner.WriteString("\n")

	for _, line := range strings.Split(footerWrapped, "\n") {
		inner.WriteString(lipgloss.PlaceHorizontal(targetW, lipgloss.Center, SubtitleStyle.Render(line)))
		inner.WriteString("\n")
	}

	box := BorderStyle.Render(inner.String())
	var b strings.Builder
	b.WriteString(lipgloss.PlaceHorizontal(t.width, lipgloss.Center, box))
	return b.String()
}

func (t *SnippetListTab) Close() {}

// SetSnippets updates the snippet list data directly (used for refresh)
func (t *SnippetListTab) SetSnippets(snippets []*models.Snippet) {
	t.mu.Lock()
	defer t.mu.Unlock()
	t.state = snippetListReady
	t.snippets = snippets
}

// FindSnippetListTab finds the first SnippetListTab in a list of tabs
func FindSnippetListTab(tabs []Tab) *SnippetListTab {
	for _, tab := range tabs {
		if st, ok := tab.(*SnippetListTab); ok {
			return st
		}
	}
	return nil
}

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