package tui

import (
	"fmt"
	"strings"
	"time"

	"gitea.lerkolabs.com/lerkolabs/uptop/internal/models"
	"github.com/charmbracelet/lipgloss"
)

func (m Model) viewMaintDetailPanel() string {
	mw := m.findMaintWindow(m.maintDetailID)
	if mw == nil {
		return lipgloss.NewStyle().Padding(1, 2).Render(m.st.subtleStyle.Render("Maintenance window not found"))
	}

	var b strings.Builder

	header := "  " + m.st.subtleStyle.Render("Maintenance >") + " " + m.st.titleStyle.Render(mw.Title)
	b.WriteString(header + "\n")
	b.WriteString(m.divider() + "\n")

	row := func(label, value string) {
		fmt.Fprintf(&b, "  %-16s %s\n", m.st.subtleStyle.Render(label), value)
	}

	maintType := m.st.maintStyle.Render("maintenance")
	if mw.Type == "incident" {
		maintType = m.st.dangerStyle.Render("incident")
	}
	row("Type", maintType)

	now := time.Now()
	if mw.StartTime.After(now) {
		row("Status", m.st.warnStyle.Render("SCHEDULED"))
	} else if !mw.EndTime.IsZero() && mw.EndTime.Before(now) {
		row("Status", m.st.subtleStyle.Render("ENDED"))
	} else {
		row("Status", m.st.specialStyle.Render("ACTIVE"))
	}

	if mw.MonitorID == 0 {
		row("Monitors", "All")
	} else {
		name := fmt.Sprintf("#%d", mw.MonitorID)
		allSites := m.engine.GetAllSites()
		for _, s := range allSites {
			if s.ID == mw.MonitorID {
				name = s.Name
				break
			}
		}
		row("Monitors", name)
	}

	row("Started", mw.StartTime.Format("2006-01-02 15:04"))
	if mw.EndTime.IsZero() {
		row("Ends", m.st.subtleStyle.Render("indefinite"))
	} else {
		row("Ends", mw.EndTime.Format("2006-01-02 15:04"))
		if mw.EndTime.After(now) && !mw.StartTime.After(now) {
			remaining := time.Until(mw.EndTime)
			row("Remaining", fmtDuration(remaining))
		}
		dur := mw.EndTime.Sub(mw.StartTime)
		row("Duration", fmtDuration(dur))
	}

	if mw.Description != "" {
		b.WriteString("\n")
		row("Description", mw.Description)
	}

	b.WriteString("\n" + m.divider() + "\n")

	var keys []string
	isActive := !mw.StartTime.After(now) && (mw.EndTime.IsZero() || mw.EndTime.After(now))
	if isActive {
		keys = append(keys, "[x] End")
	}
	keys = append(keys, "[d] Delete", "[q/Esc] Back")
	b.WriteString("  " + m.st.subtleStyle.Render(strings.Join(keys, "  ")))

	return lipgloss.NewStyle().Padding(1, 2).Render(b.String())
}

func (m Model) activeMaintWindows() []models.MaintenanceWindow {
	now := time.Now()
	var out []models.MaintenanceWindow
	for _, mw := range m.maintenanceWindows {
		if !mw.EndTime.IsZero() && mw.EndTime.Before(now) {
			continue
		}
		out = append(out, mw)
	}
	return out
}

func (m Model) viewMaintSidebar(width, maxLines int) string {
	windows := m.activeMaintWindows()
	if len(windows) == 0 {
		return m.st.subtleStyle.Render(" No active maintenance")
	}

	contentW := width - 2
	if contentW < 10 {
		contentW = 10
	}

	start := m.maintOffset
	if start > len(windows) {
		start = len(windows)
	}
	linesUsed := 0
	end := start
	for end < len(windows) && linesUsed+2 <= maxLines {
		linesUsed += 2
		end++
	}

	var lines []string
	now := time.Now()
	for i := start; i < end; i++ {
		mw := windows[i]
		selected := m.focusedPanel == panelMaint && i == m.maintCursor

		isActive := !mw.StartTime.After(now) && (mw.EndTime.IsZero() || mw.EndTime.After(now))

		var icon string
		if isActive {
			icon = m.st.specialStyle.Render("●")
		} else {
			icon = m.st.warnStyle.Render("○")
		}

		title := limitStr(mw.Title, contentW-3)
		titleLine := " " + icon + " " + title

		var detail string
		if isActive {
			if mw.EndTime.IsZero() {
				detail = m.st.subtleStyle.Render("active · indefinite")
			} else {
				remaining := time.Until(mw.EndTime)
				detail = m.st.subtleStyle.Render("active · " + fmtDuration(remaining))
			}
		} else {
			detail = m.st.subtleStyle.Render(mw.StartTime.Format("Jan 02") + " · " + fmtDuration(mw.EndTime.Sub(mw.StartTime)))
		}
		detailLine := "   " + limitStr(detail, contentW-3)

		if selected {
			sel := m.st.tableSelectedStyle
			titleLine = sel.Render(lipgloss.NewStyle().Width(contentW).Render(titleLine))
			detailLine = sel.Render(lipgloss.NewStyle().Width(contentW).Render(detailLine))
		}

		lines = append(lines, titleLine, detailLine)
	}

	if len(windows) > end-start {
		more := fmt.Sprintf(" %d more", len(windows)-(end-start))
		lines = append(lines, m.st.subtleStyle.Render(more))
	}

	return strings.Join(lines, "\n")
}

func (m *Model) scrollMaintCursor(delta int) {
	windows := m.activeMaintWindows()
	total := len(windows)
	if total == 0 {
		return
	}
	m.maintCursor += delta
	if m.maintCursor < 0 {
		m.maintCursor = 0
	}
	if m.maintCursor >= total {
		m.maintCursor = total - 1
	}
	if m.maintCursor < m.maintOffset {
		m.maintOffset = m.maintCursor
	}
	visible := m.maxTableRows / 2
	if visible < 1 {
		visible = 1
	}
	if m.maintCursor >= m.maintOffset+visible {
		m.maintOffset = m.maintCursor - visible + 1
	}
}