ui.go

package main

import (
	"fmt"
	"strings"
	"time"

	"github.com/charmbracelet/lipgloss"
)

// =============================================================================
// Design Tokens
// =============================================================================

const appWidth = 78

var (
	// Colors
	cPrimary   = lipgloss.Color("#7D56F4")
	cPrimaryHi = lipgloss.Color("#9B7BF7")
	cSuccess   = lipgloss.Color("#04B575")
	cSuccessHi = lipgloss.Color("#06D68E")
	cDanger    = lipgloss.Color("#FF4757")
	cDangerHi  = lipgloss.Color("#FF6B81")
	cWarning   = lipgloss.Color("#F4D03F")
	cText      = lipgloss.Color("#E8E8E8")
	cTextDim   = lipgloss.Color("#A0A0B0")
	cMuted     = lipgloss.Color("#6C6C80")
	cBorder    = lipgloss.Color("#3A3A50")
	cBgPanel   = lipgloss.Color("#1E1E2E")
	cBgHeader  = lipgloss.Color("#16161E")
)

// =============================================================================
// Reusable Styles
// =============================================================================

var (
	// Header bar (always visible)
	headerBar = lipgloss.NewStyle().
			Background(cBgHeader).
			Foreground(cText).
			Width(appWidth).
			Padding(0, 2).
			Render

	headerTitle = lipgloss.NewStyle().
			Bold(true).
			Foreground(cPrimaryHi).
			Render

	headerMeta = lipgloss.NewStyle().
			Foreground(cMuted).
			Render

	// License pill
	pillActive = lipgloss.NewStyle().
			Background(cPrimary).
			Foreground(lipgloss.Color("#FFFFFF")).
			Padding(0, 1).
			Bold(true).
			Render

	pillTrial = lipgloss.NewStyle().
			Background(cWarning).
			Foreground(lipgloss.Color("#000000")).
			Padding(0, 1).
			Bold(true).
			Render

	pillExpired = lipgloss.NewStyle().
			Background(cDanger).
			Foreground(lipgloss.Color("#FFFFFF")).
			Padding(0, 1).
			Bold(true).
			Render

	// Breadcrumb
	crumbActive = lipgloss.NewStyle().
			Foreground(cPrimaryHi).
			Bold(true).
			Render

	crumbDone = lipgloss.NewStyle().
			Foreground(cSuccess).
			Render

	crumbPending = lipgloss.NewStyle().
			Foreground(cMuted).
			Render

	crumbArrow = lipgloss.NewStyle().
			Foreground(cBorder).
			Render

	// Panels
	panel = lipgloss.NewStyle().
		BorderStyle(lipgloss.RoundedBorder()).
		BorderForeground(cBorder).
		Background(cBgPanel).
		Padding(1, 2).
		Width(appWidth - 4)

	panelSuccess = lipgloss.NewStyle().
			BorderStyle(lipgloss.RoundedBorder()).
			BorderForeground(cSuccess).
			Background(cBgPanel).
			Padding(1, 2).
			Width(appWidth - 4)

	panelError = lipgloss.NewStyle().
			BorderStyle(lipgloss.RoundedBorder()).
			BorderForeground(cDanger).
			Background(cBgPanel).
			Padding(1, 2).
			Width(appWidth - 4)

	// Typography
	title = lipgloss.NewStyle().
		Bold(true).
		Foreground(cPrimaryHi).
		MarginBottom(1)

	subtitle = lipgloss.NewStyle().
			Foreground(cTextDim).
			MarginBottom(1)

	body = lipgloss.NewStyle().
		Foreground(cText)

	hint = lipgloss.NewStyle().
		Foreground(cMuted).
		Italic(true)

	label = lipgloss.NewStyle().
		Foreground(cTextDim).
		Width(16).
		Align(lipgloss.Right).
		PaddingRight(1)

	value = lipgloss.NewStyle().
		Foreground(cText).
		Bold(true)

	valueHighlight = lipgloss.NewStyle().
			Foreground(cWarning).
			Bold(true)

	valueSuccess = lipgloss.NewStyle().
			Foreground(cSuccessHi).
			Bold(true)

	// Interactive elements
	choiceSelected = lipgloss.NewStyle().
			Foreground(cSuccessHi).
			Bold(true).
			PaddingLeft(2)

	choiceNormal = lipgloss.NewStyle().
			Foreground(cText).
			PaddingLeft(2)

	choiceDesc = lipgloss.NewStyle().
			Foreground(cMuted).
			PaddingLeft(4)

	// Footer
	footer = lipgloss.NewStyle().
		Foreground(cMuted).
		Width(appWidth).
		Align(lipgloss.Center).
		MarginTop(1)

	// Progress
	progressLabel = lipgloss.NewStyle().
			Foreground(cTextDim).
			Width(12).
			Render

	progressValue = lipgloss.NewStyle().
			Foreground(cPrimaryHi).
			Bold(true).
			Width(10).
			Align(lipgloss.Right).
			Render

	// Big numbers
	bigNumber = lipgloss.NewStyle().
			Foreground(cPrimaryHi).
			Bold(true).
			Width(10).
			Align(lipgloss.Right).
			Render
)

// =============================================================================
// Main View Router
// =============================================================================

func renderView(m model) string {
	var sections []string

	// Persistent header
	sections = append(sections, renderHeader())

	// Breadcrumb (hidden on error/license screen)
	if m.step != stepError {
		sections = append(sections, renderBreadcrumb(m.step))
	}

	// Main content
	switch m.step {
	case stepSelectDB:
		sections = append(sections, renderDBSelection(m))
	case stepInputRows:
		sections = append(sections, renderRowInput(m))
	case stepRunning:
		sections = append(sections, renderRunning(m))
	case stepSuccess:
		sections = append(sections, renderSuccess(m))
	case stepError:
		sections = append(sections, renderError(m))
	}

	// Footer
	sections = append(sections, footer.Render(renderFooter(m)))

	return lipgloss.JoinVertical(lipgloss.Center, sections...)
}

// =============================================================================
// Header (Persistent)
// =============================================================================

func renderHeader() string {
	lic := LoadAndVerifyLicense()

	left := headerTitle("⚡ DATA-MOCKER")
	right := ""

	if lic.Valid {
		if lic.IsTrial() {
			right = pillTrial(fmt.Sprintf("TRIAL %dd", lic.DaysRemaining()))
		} else {
			right = pillActive(strings.ToUpper(string(lic.Claims.Tier)))
		}
	} else {
		right = pillExpired("EXPIRED")
	}

	// Pad between left and right
	padWidth := appWidth - lipgloss.Width(left) - lipgloss.Width(right) - 4
	if padWidth < 1 {
		padWidth = 1
	}
	padding := strings.Repeat(" ", padWidth)

	return headerBar(lipgloss.JoinHorizontal(lipgloss.Left, left, padding, right))
}

// =============================================================================
// Breadcrumb
// =============================================================================

func renderBreadcrumb(step int) string {
	steps := []string{"Database", "Amount", "Generate", "Done"}
	var parts []string

	for i, label := range steps {
		var s string
		switch {
		case i == step:
			s = crumbActive(label)
		case i < step:
			s = crumbDone("✓ " + label)
		default:
			s = crumbPending(label)
		}
		parts = append(parts, s)
		if i < len(steps)-1 {
			parts = append(parts, crumbArrow("›"))
		}
	}

	return lipgloss.NewStyle().
		Width(appWidth).
		Align(lipgloss.Center).
		MarginTop(1).
		MarginBottom(1).
		Render(lipgloss.JoinHorizontal(lipgloss.Center, parts...))
}

// =============================================================================
// Step 0: Database Selection
// =============================================================================

func renderDBSelection(m model) string {
	var b strings.Builder

	b.WriteString(title.Render("Choose Your Database Engine") + "\n")
	b.WriteString(subtitle.Render("Pick the engine that fits your workflow") + "\n\n")

	engines := []struct {
		name   string
		desc   string
		badge  string
		badgeC lipgloss.Color
	}{
		{"PostgreSQL", "Fastest. Binary COPY protocol for millions of rows.", "RECOMMENDED", cSuccess},
		{"MySQL", "Widely compatible. Optimized batch INSERT.", "", cMuted},
		{"SQLite", "Zero setup. Instant file-based database.", "QUICK", cWarning},
	}

	for i, eng := range engines {
		icon := "  "
		style := choiceNormal
		if m.cursor == i {
			icon = "▸ "
			style = choiceSelected
		}

		b.WriteString(style.Render(fmt.Sprintf("%s%s", icon, eng.name)) + "\n")
		b.WriteString(choiceDesc.Render(eng.desc) + "\n")

		if eng.badge != "" {
			badge := lipgloss.NewStyle().
				Foreground(eng.badgeC).
				Bold(true).
				PaddingLeft(4).
				Render("[" + eng.badge + "]")
			b.WriteString(badge + "\n")
		}
		b.WriteString("\n")
	}

	b.WriteString(hint.Render("Tip: SQLite needs no Docker — perfect for first-time users.") + "\n")

	return panel.Render(b.String())
}

// =============================================================================
// Step 1: Row Count Input
// =============================================================================

func renderRowInput(m model) string {
	var b strings.Builder

	b.WriteString(title.Render("How Many Rows?") + "\n")

	// Selected DB badge
	dbBadge := lipgloss.NewStyle().
		Background(cPrimary).
		Foreground(lipgloss.Color("#FFFFFF")).
		Padding(0, 1).
		Bold(true).
		Render(" " + m.selectedDB + " ")

	b.WriteString(subtitle.Render("Target: "+dbBadge) + "\n\n")
	b.WriteString(body.Render("Enter the number of mock rows to generate.") + "\n")
	b.WriteString(hint.Render("Tip: 1,000 for testing  •  100,000 for benchmarks  •  1,000,000+ for stress tests") + "\n\n")

	// Input box
	inputBox := lipgloss.NewStyle().
		BorderStyle(lipgloss.RoundedBorder()).
		BorderForeground(cPrimary).
		Padding(0, 1).
		Width(30).
		Render(m.rowInput.View())

	b.WriteString(inputBox + "\n")

	return panel.Render(b.String())
}

// =============================================================================
// Step 2: Running / Progress Dashboard
// =============================================================================

func renderRunning(m model) string {
	var b strings.Builder

	b.WriteString(title.Render("Generating Data") + "\n\n")

	if m.connStr == "" {
		b.WriteString(m.spinner.View() + "  ")
		b.WriteString(body.Render("Provisioning container...") + "\n")
		b.WriteString(hint.Render("    Pulling image on first run. This may take 30–60 seconds.") + "\n")
	} else {
		b.WriteString(m.spinner.View() + "  ")
		b.WriteString(body.Render(fmt.Sprintf("Streaming into %s", m.selectedDB)) + "\n\n")

		// Progress bar
		b.WriteString(m.progress.View() + "\n\n")

		// Stats dashboard
		b.WriteString(renderDivider() + "\n")
		b.WriteString(renderStatRow("Progress", fmt.Sprintf("%.1f%%", m.percent*100), false))
		b.WriteString(renderStatRow("Rows", fmt.Sprintf("%s / %s", formatNumber(m.rowsWritten), formatNumber(m.targetRows)), true))
		b.WriteString(renderStatRow("Speed", fmt.Sprintf("%s rows/sec", formatNumber(m.speed)), false))
		b.WriteString(renderStatRow("Elapsed", m.elapsed.Round(time.Second).String(), false))
		b.WriteString(renderDivider() + "\n")

		// ETA estimate
		if m.speed > 0 && m.percent < 1.0 {
			remaining := m.targetRows - m.rowsWritten
			etaSec := remaining / m.speed
			if etaSec > 0 {
				eta := time.Duration(etaSec) * time.Second
				b.WriteString("\n" + hint.Render(fmt.Sprintf("⏱ Estimated time remaining: %s", eta.Round(time.Second))))
			}
		}
	}

	return panel.Render(b.String())
}

// =============================================================================
// Step 3: Success Celebration
// =============================================================================

func renderSuccess(m model) string {
	var b strings.Builder

	// Celebration banner
	b.WriteString(lipgloss.NewStyle().
		Width(appWidth).
		Align(lipgloss.Center).
		Foreground(cSuccessHi).
		Bold(true).
		Render("✨ GENERATION COMPLETE ✨") + "\n\n")

	// Stats box
	var stats strings.Builder
	stats.WriteString(renderStatRow("Total Rows", formatNumber(m.rowsWritten), true))
	stats.WriteString(renderStatRow("Time", m.elapsed.Round(time.Millisecond).String(), false))
	stats.WriteString(renderStatRow("Database", m.selectedDB, false))

	// Connection string in a copy-friendly box
	connBox := lipgloss.NewStyle().
		BorderStyle(lipgloss.RoundedBorder()).
		BorderForeground(cPrimary).
		Background(lipgloss.Color("#252535")).
		Padding(1, 2).
		Width(appWidth - 12).
		Render(lipgloss.NewStyle().
			Foreground(cPrimaryHi).
			Bold(true).
			Render(m.connStr))

	stats.WriteString(renderStatRow("Connection", "", false))
	stats.WriteString("  " + connBox + "\n")

	if m.containerID != "" {
		stats.WriteString(renderStatRow("Container", m.containerID[:12], false))
	}

	b.WriteString(panelSuccess.Render(stats.String()) + "\n\n")

	// Next steps
	b.WriteString(body.Render("What would you like to do next?") + "\n")
	b.WriteString(hint.Render("• Connect: Use the connection string above with DBeaver, TablePlus, or psql") + "\n")
	b.WriteString(hint.Render("• Export: Run with --format csv to generate files without a database") + "\n")
	b.WriteString(hint.Render("• Schema: Use --schema to define custom tables and foreign keys") + "\n")

	return b.String()
}

// =============================================================================
// Step -1: Error (Helpful, Not Punishing)
// =============================================================================

func renderError(m model) string {
	var b strings.Builder

	b.WriteString(lipgloss.NewStyle().
		Width(appWidth).
		Align(lipgloss.Center).
		Foreground(cDangerHi).
		Bold(true).
		Render("⚠ SOMETHING WENT WRONG") + "\n\n")

	// Error detail box
	errBox := lipgloss.NewStyle().
		Foreground(cDanger).
		Bold(true).
		Render(fmt.Sprintf("%v", m.err))

	b.WriteString(panelError.Render(errBox) + "\n\n")

	// Suggested fixes
	b.WriteString(body.Render("Try these fixes:") + "\n")

	suggestions := []string{
		"Ensure Docker Desktop is running (for PostgreSQL / MySQL)",
		"Pick SQLite for zero-setup testing",
		"Reduce row count if memory is limited",
		"Check your license with: ./datamocker --license",
	}

	for _, s := range suggestions {
		b.WriteString(hint.Render("  • "+s) + "\n")
	}

	b.WriteString("\n" + body.Render("Press Enter to go back  •  Q to quit") + "\n")

	return b.String()
}

// =============================================================================
// License Screen (Fallback)
// =============================================================================

func renderLicenseScreen() string {
	lic := LoadAndVerifyLicense()
	var b strings.Builder

	b.WriteString(lipgloss.NewStyle().
		Width(appWidth).
		Align(lipgloss.Center).
		Foreground(cDangerHi).
		Bold(true).
		Render("🔒 LICENSE REQUIRED") + "\n\n")

	if lic.Error != "" {
		b.WriteString(lipgloss.NewStyle().
			Foreground(cDanger).
			Render(lic.Error) + "\n\n")
	}

	b.WriteString(body.Render("Purchase a license at:") + "\n")
	b.WriteString(lipgloss.NewStyle().
		Foreground(cPrimaryHi).
		Bold(true).
		Underline(true).
		Render("https://datamocker.dev") + "\n\n")

	b.WriteString(hint.Render("Or place a valid .datamocker_license file in your home directory.") + "\n\n")

	if lic.IsTrial() && lic.DaysRemaining() > 0 {
		b.WriteString(lipgloss.NewStyle().
			Foreground(cWarning).
			Bold(true).
			Render(fmt.Sprintf("⏱ Trial expires in %d days", lic.DaysRemaining())) + "\n")
	}

	b.WriteString("\n" + footer.Render("Press Q to exit"))
	return b.String()
}

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

func renderDivider() string {
	return lipgloss.NewStyle().
		Foreground(cBorder).
		Render(strings.Repeat("─", appWidth-8))
}

func renderStatRow(name, val string, highlight bool) string {
	valStyle := value
	if highlight {
		valStyle = valueHighlight
	}
	return lipgloss.JoinHorizontal(lipgloss.Left,
		label.Render(name),
		valStyle.Render(val),
	) + "\n"
}

func renderFooter(m model) string {
	switch m.step {
	case stepSelectDB:
		return "↑/↓ select  •  Enter confirm  •  Q quit"
	case stepInputRows:
		return "Enter confirm  •  Esc back  •  Q quit"
	case stepRunning:
		return "Please wait...  •  Ctrl+C to cancel"
	case stepSuccess:
		return "Enter new session  •  Q quit"
	case stepError:
		return "Enter retry  •  Q quit"
	default:
		return "↑/↓ navigate  •  Enter confirm  •  Q quit"
	}
}

func formatNumber(n int) string {
	if n < 1000 {
		return fmt.Sprintf("%d", n)
	}
	if n < 1000000 {
		return fmt.Sprintf("%.1fK", float64(n)/1000)
	}
	return fmt.Sprintf("%.2fM", float64(n)/1000000)
}