package state

import (
	"fmt"
	"github.com/rs/xid"
	"go.uber.org/zap/zapcore"
)

// HexOrientation is the enum for the direction hexes are facing.
type HexOrientation uint8

const (
	// UnknownOrientation indicates that an invalid orientation was specified.
	UnknownOrientation HexOrientation = 0
	// PointyTop indicates hexes that have a pair of sides on either side in the horizontal direction,
	// and points on the top and bottom in the vertical direction.
	PointyTop HexOrientation = 1
	// FlatTop indicates hexes that have a pair of points on either side in the horizontal direction,
	// and sides on the top and bottom in the vertical direction.
	FlatTop HexOrientation = 2
)

// String returns the equivalent JavaScript constant name.
func (o HexOrientation) String() string {
	switch o {
	case PointyTop:
		return "POINTY_TOP"
	case FlatTop:
		return "FLAT_TOP"
	default:
		return fmt.Sprintf("[unknown HexOrientation %d]", o)
	}
}

// LineParity indicates whether odd or even lines are indented.
type LineParity uint8

const (
	// UnknownParity indicates that parity was not specified or unknown.
	UnknownParity LineParity = 0
	// OddLines indicates that odd lines - 1, 3, 5... - are indented by 1/2 cell.
	OddLines LineParity = 1
	// EvenLines indicates that even lines - 0, 2, 4... - are indented by 1/2 cell.
	EvenLines LineParity = 2
)

// String returns the equivalent JavaScript constant name.
func (o LineParity) String() string {
	switch o {
	case OddLines:
		return "ODD_LINES"
	case EvenLines:
		return "EVEN_LINES"
	default:
		return fmt.Sprintf("[unknown LineParity %d]", o)
	}
}

// Layout combines HexOrientation and LineParity to represent a map's display mode.
type Layout struct {
	Orientation   HexOrientation `json:"orientation"`
	IndentedLines LineParity     `json:"indentedLines"`
}

func (l Layout) MarshalLogObject(encoder zapcore.ObjectEncoder) error {
	encoder.AddString("orientation", l.Orientation.String())
	encoder.AddString("indentedLines", l.IndentedLines.String())
	return nil
}

// HexCell contains data for a single cell of the map.
type HexCell struct {
	// Color contains the color of the cell, in hex notation.
	Color Color `json:"color"`
}

func (h HexCell) MarshalLogObject(encoder zapcore.ObjectEncoder) error {
	encoder.AddString("color", h.Color.String())
	return nil
}

// HexLine is a line of cells which are adjacent by flat sides in a vertical or horizontal direction.
type HexLine []HexCell

func (l HexLine) MarshalLogArray(encoder zapcore.ArrayEncoder) error {
	var finalErr error
	for _, cell := range l {
		err := encoder.AppendObject(cell)
		if err != nil && finalErr == nil {
			finalErr = err
		}
	}
	return finalErr
}

// Copy creates a deep copy of this HexLine.
func (l HexLine) Copy() HexLine {
	duplicate := make(HexLine, len(l))
	for index, value := range l {
		duplicate[index] = value
	}
	return duplicate
}

// HexLayer is a two-dimensional plane of cells which are arranged into lines.
type HexLayer []HexLine

func (l HexLayer) MarshalLogArray(encoder zapcore.ArrayEncoder) error {
	var finalErr error
	for _, line := range l {
		err := encoder.AppendArray(line)
		if err != nil && finalErr == nil {
			finalErr = err
		}
	}
	return finalErr
}

// GetCellAt returns a reference to the cell at the given coordinates.
// If the coordinates are out of bounds for this map, an error will be returned.
func (l HexLayer) GetCellAt(c StorageCoordinates) (*HexCell, error) {
	if int(c.Line) > len(l) {
		return nil, fmt.Errorf("line %d out of bounds (%d)", c.Line, len(l))
	}
	line := l[c.Line]
	if int(c.Cell) > len(line) {
		return nil, fmt.Errorf("cell %d out of bounds (%d)", c.Cell, len(line))
	}
	return &(line[c.Cell]), nil
}

// Copy creates a deep copy of this HexLayer.
func (l HexLayer) Copy() HexLayer {
	duplicate := make(HexLayer, len(l))
	for index, value := range l {
		duplicate[index] = value.Copy()
	}
	return duplicate
}

// HexMap contains the data for a map instance.
type HexMap struct {
	// XID is the unique id of the HexMap, used to encourage clients not to blindly interact with a different map.
	XID xid.ID `json:"xid"`
	// Lines is the rough number of rows (in PointyTop orientation) or columns (in FlatTop orientation) in the map.
	// Because different lines will be staggered, it's somewhat hard to see.
	Lines uint8 `json:"lines"`
	// CellsPerLine is the rough number of columns (in PointyTop orientation) or rows (in FlatTop orientation).
	// This is the number of cells joined together, flat-edge to flat-edge, in each line.
	CellsPerLine uint8 `json:"cellsPerLine"`
	// Layout is the orientation and line parity used to display the map.
	Layout Layout `json:"displayMode"`
	// Layer contains the actual map data.
	// Layer itself is a slice with Lines elements, each of which is a line;
	// each of those lines is a slice of CellsPerLine cells.
	Layer HexLayer `json:"lineCells"`
}

func (m HexMap) MarshalLogObject(encoder zapcore.ObjectEncoder) error {
	encoder.AddString("id", m.XID.String())
	encoder.AddUint8("lines", m.Lines)
	encoder.AddUint8("cellsPerLine", m.CellsPerLine)
	displayModeErr := encoder.AddObject("displayMode", m.Layout)
	lineCellsErr := encoder.AddArray("lineCells", m.Layer)
	if displayModeErr != nil {
		return displayModeErr
	} else {
		return lineCellsErr
	}
}

// Copy creates a deep copy of this HexMap.
func (m HexMap) Copy() HexMap {
	return HexMap{
		XID:          m.XID,
		Lines:        m.Lines,
		CellsPerLine: m.CellsPerLine,
		Layout:       m.Layout,
		Layer:        m.Layer.Copy(),
	}
}