package main

import (
	"fmt"
	"regexp"

	todo "github.com/1set/todotxt"
	"github.com/charmbracelet/lipgloss"

	catppuccin "github.com/catppuccin/go"
)

var DATETIME_FORMAT = "02-01-2006 15:03"
var DATE_FORMAT = "02-01-2006"

var Catppuccin catppuccin.Flavor = catppuccin.Mocha

type Style struct {
	Task     TaskStyle
	Priority PriorityStyle
	Date     DateStyle
	Check    lipgloss.Style
	Context  lipgloss.Style
	Project  lipgloss.Style
	KeyValue lipgloss.Style
}

type TaskStyle struct {
	Todo      lipgloss.Style
	Completed lipgloss.Style
}

type PriorityStyle struct {
	A lipgloss.Style
	B lipgloss.Style
	C lipgloss.Style
}

type DateStyle struct {
	done    lipgloss.Style
	today   lipgloss.Style
	overdue lipgloss.Style
	futur   lipgloss.Style
}

func NewTextStyle() Style {

	taskStyle := TaskStyle{
		Todo:      lipgloss.NewStyle().Foreground(lipgloss.Color(Catppuccin.Text().Hex)),
		Completed: lipgloss.NewStyle().Strikethrough(true).Foreground(lipgloss.Color(Catppuccin.Overlay2().Hex)),
	}

	priorityStyle := PriorityStyle{
		A: lipgloss.NewStyle().Foreground(lipgloss.Color(Catppuccin.Red().Hex)),
		B: lipgloss.NewStyle().Foreground(lipgloss.Color(Catppuccin.Peach().Hex)),
		C: lipgloss.NewStyle().Foreground(lipgloss.Color(Catppuccin.Green().Hex)),
	}

	dateBaseStyle := lipgloss.NewStyle()
	dateStyle := DateStyle{
		done:    dateBaseStyle.Foreground(lipgloss.Color(Catppuccin.Overlay0().Hex)),
		today:   dateBaseStyle.Foreground(lipgloss.Color(Catppuccin.Crust().Hex)).Background(lipgloss.Color(Catppuccin.Blue().Hex)),
		overdue: dateBaseStyle.Foreground(lipgloss.Color(Catppuccin.Crust().Hex)).Background(lipgloss.Color(Catppuccin.Red().Hex)),
		futur:   dateBaseStyle.Foreground(lipgloss.Color(Catppuccin.Blue().Hex)),
	}

	style := Style{
		Priority: priorityStyle,
		Task:     taskStyle,
		Date:     dateStyle,
		Check:    lipgloss.NewStyle().Foreground(lipgloss.Color(Catppuccin.Blue().Hex)),
		Context:  lipgloss.NewStyle().Foreground(lipgloss.Color(Catppuccin.Blue().Hex)),
		Project:  lipgloss.NewStyle().Foreground(lipgloss.Color(Catppuccin.Mauve().Hex)),
		KeyValue: lipgloss.NewStyle().Foreground(lipgloss.Color(Catppuccin.Flamingo().Hex)),
	}
	return style
}

func (s Style) getTaskStyle(task todo.Task, checked bool) string {

	todoText := task.Original

	checkedRegex := regexp.MustCompile(`^x (\d{4}-\d{2}-\d{2} )? ?`)
	priorityRegex := regexp.MustCompile(`^\([A-Z]\) `)
	contextRegex := regexp.MustCompile(`@\w+`)
	projectRegex := regexp.MustCompile(`\+\w+`)
	dueDateRegex := regexp.MustCompile(`due:\d{4}-\d{2}-\d{2}`)
	keyValueRegex := regexp.MustCompile(`\w+:.+`)

	todoText = checkedRegex.ReplaceAllString(todoText, "")
	todoText = priorityRegex.ReplaceAllString(todoText, "")
	todoText = dueDateRegex.ReplaceAllString(todoText, "")

	checkString := " "
	if checked {
		checkString = "✓"
	}

	switch task.Completed {
	case true:
		dateString := s.Date.done.Render(task.CompletedDate.Local().Format(DATETIME_FORMAT))
		return fmt.Sprintf("%s %s %s %s", s.Check.Render(checkString), s.getPriorityStyle(task.Priority), s.Task.Completed.Render(todoText), dateString)
	default:
		todoText = contextRegex.ReplaceAllStringFunc(todoText, func(match string) string {
			return s.Context.Render(match)
		})
		todoText = projectRegex.ReplaceAllStringFunc(todoText, func(match string) string {
			return s.Project.Render(match)
		})
		todoText = keyValueRegex.ReplaceAllStringFunc(todoText, func(match string) string {
			return s.KeyValue.Render(match)
		})
		var dueDateString string
		if task.HasDueDate() {
			formatedDueDate := task.DueDate.Format(DATE_FORMAT)
			switch {
			case task.IsDueToday():
				dueDateString = s.Date.today.Render(formatedDueDate)
			case task.IsOverdue():
				dueDateString = s.Date.overdue.Render(formatedDueDate)
			default:
				dueDateString = s.Date.futur.Render(formatedDueDate)
			}
		}
		return fmt.Sprintf("%s %s %s %s", s.Check.Render(checkString), s.getPriorityStyle(task.Priority), s.Task.Todo.Render(todoText), dueDateString)
	}
}

func (s Style) getPriorityStyle(priority string) string {
	switch priority {
	case "":
		return " "
	case "A":
		return s.Priority.A.Render(priority)
	case "B":
		return s.Priority.B.Render(priority)
	case "C":
		return s.Priority.C.Render(priority)
	default:
		return priority
	}
}