package day7_pg

import (
	"iter"

	"git.bizdoc.ro/private/devkit.git/collections/dsa"
	"git.bizdoc.ro/private/devkit.git/collections/geometry/v2"
)

type Day7Part1RenderEvent struct {
	Point          geometry.Point
	Grid           geometry.Grid[byte]
	TotalProcessed int64
	Step           int
}

func Day7ProgressFillPart1(g geometry.Grid[byte], start geometry.Point) iter.Seq[Day7Part1RenderEvent] {
	return func(yield func(Day7Part1RenderEvent) bool) {
		stack := dsa.NewStack[geometry.Point]()
		stack.Push(start)

		ev := Day7Part1RenderEvent{
			Point:          start,
			Grid:           g,
			TotalProcessed: 0,
		}
		for !stack.IsEmpty() {
			start := stack.Pop()
			if g.ContainsPoint(start) {
				switch g.At(start) {
				case 'S':
					stack.Push(start.MoveDown())
				case '.':
					g.Set(start, '|')
					stack.Push(start.MoveDown())
				case '^':
					stack.Push(start.MoveRight())
					stack.Push(start.MoveLeft())
					ev.TotalProcessed += 1
				}
			}
			ev.Step += 1
			if !yield(ev) {
				return
			}
		}
	}
}