package tui

import (
	"context"
	"database/sql"
	"errors"
	"fmt"
	"slices"
	"time"

	"punchcard/internal/queries"

	"github.com/charmbracelet/lipgloss/v2"
)

var (
	// Styles for the TUI
	topBarInactiveStyle = lipgloss.NewStyle().
				Background(lipgloss.Color("21")).
				Foreground(lipgloss.Color("230")).
				Padding(0, 1)

	bottomBarStyle = lipgloss.NewStyle().
			Background(lipgloss.Color("238")).
			Foreground(lipgloss.Color("252"))

	// Box styles
	selectedBoxStyle = lipgloss.NewStyle().
				Border(lipgloss.RoundedBorder()).
				BorderForeground(lipgloss.Color("62")).
				Padding(1, 2)

	unselectedBoxStyle = lipgloss.NewStyle().
				Border(lipgloss.RoundedBorder()).
				BorderForeground(lipgloss.Color("238")).
				Padding(1, 2)

	activeTimerStyle = lipgloss.NewStyle().
				Foreground(lipgloss.Color("196")).
				Bold(true)

	inactiveTimerStyle = lipgloss.NewStyle().
				Foreground(lipgloss.Color("246"))
)

// FormatDuration formats a duration in a human-readable way
func FormatDuration(d time.Duration) string {
	d = d.Round(time.Second)
	hours := int(d.Hours())
	minutes := int(d.Minutes()) % 60
	seconds := int(d.Seconds()) % 60

	if hours > 0 {
		return fmt.Sprintf("%dh %02dm %02ds", hours, minutes, seconds)
	}
	if minutes > 0 {
		return fmt.Sprintf("%dm %02ds", minutes, seconds)
	}
	return fmt.Sprintf("%ds", seconds)
}

func getTimerInfo(ctx context.Context, q *queries.Queries) (TimerInfo, error) {
	var info TimerInfo

	activeEntry, err := q.GetActiveTimeEntry(ctx)
	if err != nil && !errors.Is(err, sql.ErrNoRows) {
		return info, fmt.Errorf("failed to get active timer: %w", err)
	}
	if err != nil {
		return getMostRecentTimerInfo(ctx, q)
	}

	info.IsActive = true
	info.EntryID = activeEntry.ID
	info.Duration = time.Since(activeEntry.StartTime)
	info.StartTime = activeEntry.StartTime
	info.ClientID = activeEntry.ClientID
	if activeEntry.ProjectID.Valid {
		info.ProjectID = &activeEntry.ProjectID.Int64
	}
	if activeEntry.Description.Valid {
		info.Description = &activeEntry.Description.String
	}
	if activeEntry.BillableRate.Valid {
		rate := float64(activeEntry.BillableRate.Int64) / 100
		info.BillableRate = &rate
	}

	return info, nil
}

func getMostRecentTimerInfo(ctx context.Context, q *queries.Queries) (TimerInfo, error) {
	var info TimerInfo

	entry, err := q.GetMostRecentTimeEntry(ctx)
	if err != nil && !errors.Is(err, sql.ErrNoRows) {
		return info, fmt.Errorf("failed to get most recent timer: %w", err)
	}
	if err != nil {
		return info, nil
	}

	info.IsActive = false
	info.EntryID = entry.ID
	info.Duration = entry.EndTime.Time.Sub(entry.StartTime)
	info.StartTime = entry.StartTime
	info.ClientID = entry.ClientID
	if entry.ProjectID.Valid {
		info.ProjectID = &entry.ProjectID.Int64
	}
	if entry.Description.Valid {
		info.Description = &entry.Description.String
	}
	if entry.BillableRate.Valid {
		rate := float64(entry.BillableRate.Int64) / 100
		info.BillableRate = &rate
	}

	return info, nil
}

// RenderTopBar renders the top bar with view name and time stats
func RenderTopBar(m AppModel) string {
	left := fmt.Sprintf("👊 Punchcard ♦️  -  %s", m.selectedBox.String())

	today := m.timeStats.TodayTotal
	week := m.timeStats.WeekTotal

	if m.timerBox.timerInfo.IsActive {
		activeTime := m.timerBox.currentTime.Sub(m.timerBox.timerInfo.StartTime)
		today += activeTime
		week += activeTime
	}

	right := fmt.Sprintf("Today: %s  |  Week: %s",
		FormatDuration(today),
		FormatDuration(week))

	// Use lipgloss to create left and right aligned content
	leftStyle := lipgloss.NewStyle().Align(lipgloss.Left)
	rightStyle := lipgloss.NewStyle().Align(lipgloss.Right)

	// Calculate available width for content (minus padding)
	contentWidth := m.width - 2 // Account for horizontal padding

	// Create a layout with left and right content
	content := lipgloss.JoinHorizontal(
		lipgloss.Top,
		leftStyle.Width(contentWidth/2).Render(left),
		rightStyle.Width(contentWidth/2).Render(right),
	)

	return topBarInactiveStyle.Width(m.width).Render(content)
}

// RenderBottomBar renders the bottom bar with key bindings
func RenderBottomBar(m AppModel, bindings []KeyBinding, err error) string {
	var content string
	for i, binding := range bindings {
		if binding.Hide {
			continue
		}
		if i > 0 {
			content += "  "
		}
		keyStyle := lipgloss.NewStyle().Bold(true)
		formattedKey := keyStyle.Render(fmt.Sprintf("[%s]", binding.Key))
		content += fmt.Sprintf("%s %s", formattedKey, binding.Description(m))
	}

	content = bottomBarStyle.Align(lipgloss.Left).Render(content)
	if err != nil {
		content = lipgloss.JoinHorizontal(
			lipgloss.Bottom,
			content,
			bottomBarStyle.Bold(true).Foreground(lipgloss.Color("196")).Align(lipgloss.Right).Render(err.Error()),
		)
	}

	return bottomBarStyle.Width(m.width).Render(content)
}

// GetAppData fetches all data needed for the TUI
func getAppData(
	ctx context.Context,
	q *queries.Queries,
) (
	info TimerInfo,
	stats TimeStats,
	clients []queries.Client,
	projectsIdx map[int64][]queries.Project,
	entries []queries.TimeEntry,
	err error,
) {
	info, err = getTimerInfo(ctx, q)
	if err != nil {
		return
	}

	clients, err = q.ListAllClients(ctx)
	if err != nil {
		return
	}
	slices.SortFunc(clients, func(a, b queries.Client) int {
		if a.Name <= b.Name {
			return -1
		}
		return 1
	})

	projects, err := q.ListAllProjects(ctx)
	if err != nil {
		return
	}
	slices.SortFunc(projects, func(a, b queries.ListAllProjectsRow) int {
		if a.Name <= b.Name {
			return -1
		}
		return 1
	})
	projectsIdx = make(map[int64][]queries.Project)
	for i := range projects {
		projectsIdx[projects[i].ClientID] = append(
			projectsIdx[projects[i].ClientID],
			queries.Project{
				ID:           projects[i].ID,
				Name:         projects[i].Name,
				ClientID:     projects[i].ClientID,
				BillableRate: projects[i].BillableRate,
				CreatedAt:    projects[i].CreatedAt,
			},
		)
	}

	entries, err = q.GetRecentTimeEntries(ctx, time.Now().Add(-time.Hour*24*14))
	if err != nil {
		return
	}

	now := time.Now()
	todayY, todayM, todayD := now.Date()
	lastMon := mostRecentMonday(now)
	inDay := true
	for i := range entries {
		e := entries[i]

		if info.IsActive && e.ID == info.EntryID {
			// skip the active timer
			continue
		}

		if inDay {
			y, m, d := e.StartTime.Date()
			if y != todayY || m != todayM || d != todayD {
				inDay = false
			}
		}

		dur := e.EndTime.Time.Sub(e.StartTime)
		if inDay {
			stats.TodayTotal += dur
			stats.WeekTotal += dur
			continue
		}

		mon := mostRecentMonday(e.StartTime)
		if mon != lastMon {
			break
		}
		stats.WeekTotal += dur
	}

	return
}

func mostRecentMonday(from time.Time) time.Time {
	d := dateOnly(from)
	dayOffset := time.Duration(d.Weekday()-1) % 7
	return d.Add(-time.Hour * 24 * dayOffset)
}