package controller

import (
	e "github.com/iliadenisov/galaxy/internal/error"
	"github.com/iliadenisov/galaxy/internal/model/game"
	"github.com/iliadenisov/galaxy/internal/util"
)

func (c *Cache) SendGroup(ri int, groupIndex, planetNumber, quantity uint) error {
	c.validateRaceIndex(ri)

	sgi, ok := c.raceShipGroupIndex(ri, groupIndex)
	if !ok {
		return e.NewEntityNotExistsError("group #%d", groupIndex)
	}
	st := c.ShipGroupShipClass(sgi)

	if st.DriveBlockMass() == 0 {
		return e.NewSendShipHasNoDrivesError()
	}

	sourcePlanet, ok := c.ShipGroup(sgi).AtPlanet()
	if !ok {
		return e.NewShipsBusyError("state: %s", c.ShipGroup(sgi).State())
	}

	if c.ShipGroup(sgi).Number < quantity {
		return e.NewBeakGroupNumberNotEnoughError("%d<%d", c.ShipGroup(sgi).Number, quantity)
	}

	p1, ok := c.Planet(sourcePlanet)
	if !ok {
		return e.NewGameStateError("source planet #%d does not exists", sourcePlanet)
	}
	p2, ok := c.Planet(planetNumber)
	if !ok {
		return e.NewEntityNotExistsError("destination planet #%d", planetNumber)
	}
	rangeToDestination := util.ShortDistance(c.g.Map.Width, c.g.Map.Height, p1.X.F(), p1.Y.F(), p2.X.F(), p2.Y.F())
	if rangeToDestination > c.g.Race[ri].FlightDistance() {
		return e.NewSendUnreachableDestinationError("range=%.03f", rangeToDestination)
	}

	if quantity > 0 && quantity < c.ShipGroup(sgi).Number {
		nsgi, err := c.breakGroupSafe(ri, groupIndex, quantity)
		if err != nil {
			return err
		}
		sgi = nsgi
	}

	if p1.Number == p2.Number {
		c.UnsendShips(c.ShipGroup(sgi))
		c.JoinEqualGroups(ri)
		return nil
	}

	c.LaunchShips(c.ShipGroup(sgi), planetNumber)

	return nil
}

func (c *Cache) LaunchShips(sg *game.ShipGroup, destination uint) *game.ShipGroup {
	for i := range c.ShipGroupsIndex() {
		if c.ShipGroup(i).OwnerID == sg.OwnerID && c.ShipGroup(i).Index == sg.Index {
			state := c.ShipGroup(i).State()
			var p *game.Planet
			switch state {
			case game.StateInOrbit:
				p = c.MustPlanet(sg.Destination)
			case game.StateLaunched:
				p = c.MustPlanet(sg.StateInSpace.Origin)
			default:
				panic("state invalid")
			}
			c.g.ShipGroups[i] = LaunchShips(*sg, destination, p.X.F(), p.Y.F())
			return &c.g.ShipGroups[i]
		}
	}
	panic("ship group not found")
}

func (c *Cache) UnsendShips(sg *game.ShipGroup) *game.ShipGroup {
	for i := range c.ShipGroupsIndex() {
		if c.ShipGroup(i).OwnerID == sg.OwnerID && c.ShipGroup(i).Index == sg.Index {
			state := c.ShipGroup(i).State()
			if state != game.StateLaunched {
				panic("state invalid")
			}
			c.g.ShipGroups[i] = UnsendShips(*sg)
			return &c.g.ShipGroups[i]
		}
	}
	panic("ship group not found")
}

func LaunchShips(sg game.ShipGroup, destination uint, originX, originY float64) game.ShipGroup {
	sg.StateInSpace = &game.InSpace{
		Origin: sg.Destination,
		X:      game.F(originX),
		Y:      game.F(originY),
	}
	sg.Destination = destination
	return sg
}

func UnsendShips(sg game.ShipGroup) game.ShipGroup {
	sg.Destination = sg.StateInSpace.Origin
	sg.StateInSpace = nil
	return sg
}