package ui

import (
	"fmt"
	"strings"

	"github.com/charmbracelet/bubbles/key"
)

// HelpModel is the help overlay model.
type HelpModel struct {
	visible bool
}

// NewHelp creates a new help model.
func NewHelp() HelpModel {
	return HelpModel{
		visible: false,
	}
}

// Show displays the help overlay.
func (m *HelpModel) Show() {
	m.visible = true
}

// Hide hides the help overlay.
func (m *HelpModel) Hide() {
	m.visible = false
}

// Toggle toggles the help overlay visibility.
func (m *HelpModel) Toggle() {
	m.visible = !m.visible
}

// IsVisible returns true if the help overlay is visible.
func (m HelpModel) IsVisible() bool {
	return m.visible
}

// Render renders the help overlay.
func (m HelpModel) Render(keys KeyMap, styles Styles) string {
	if !m.visible {
		return ""
	}

	var b strings.Builder

	// Title
	title := styles.HeaderBar.Render("Keybindings - Press ? or esc to close")
	b.WriteString(title)
	b.WriteString("\n\n")

	// Define keybinding groups
	groups := []struct {
		name  string
		binds []keyHelp
	}{
		{
			name: "Global",
			binds: []keyHelp{
				{keys.Help, "Show/hide this help"},
				{keys.Quit, "Quit the application"},
				{keys.RefreshNow, "Refresh data now"},
			},
		},
		{
			name: "Filters",
			binds: []keyHelp{
				{keys.Search, "Search by title/details"},
				{keys.Priority, "Cycle priority filter"},
				{keys.Category, "Cycle category filter"},
			},
		},
		{
			name: "Navigation",
			binds: []keyHelp{
				{keys.FocusNext, "Toggle focus (table/details)"},
				{keys.Sort, "Cycle sort order"},
				{keys.JumpToTop, "Jump to top (g)"},
				{keys.JumpToBottom, "Jump to bottom (G)"},
				{keys.Down, "Move down (j)"},
				{keys.Up, "Move up (k)"},
			},
		},
		{
			name: "Actions",
			binds: []keyHelp{
				{keys.AckToggle, "Acknowledge/unacknowledge issue"},
				{keys.Export, "Export issues to JSON"},
			},
		},
	}

	// Render each group
	for i, group := range groups {
		if i > 0 {
			b.WriteString("\n")
		}

		// Group header
		groupTitle := styles.HeaderKey.Render(group.name + ":")
		b.WriteString(groupTitle)
		b.WriteString("\n")

		// Keybindings in this group
		for _, kb := range group.binds {
			line := renderKeyHelp(kb, styles)
			b.WriteString(line)
			b.WriteString("\n")
		}
	}

	// Render collector health icon legend
	b.WriteString("\n")
	legendTitle := styles.HeaderKey.Render("Legend:")
	b.WriteString(legendTitle)
	b.WriteString("\n")
	legendText := styles.HeaderVal.Render("  Collector health: ✓ (OK), ⚠ (DEGRADED), ✗ (ERROR)")
	b.WriteString(legendText)
	b.WriteString("\n")

	return b.String()
}

type keyHelp struct {
	binding key.Binding
	help    string
}

func renderKeyHelp(kb keyHelp, styles Styles) string {
	// Get key names from the binding
	keys := kb.binding.Keys()
	if len(keys) == 0 {
		return ""
	}

	// Format key names
	keyStr := strings.Join(keys, ", ")
	keyStyled := styles.HeaderVal.Render(keyStr)

	// Format help text
	helpStyled := styles.HeaderVal.Render(kb.help)

	// Combine with padding
	padding := ""
	if needed := 10 - len(keyStr); needed > 0 {
		padding = strings.Repeat(" ", needed)
	}
	return fmt.Sprintf("  %s%s%s", keyStyled, padding, helpStyled)
}