package state

import (
	"fmt"
	"github.com/rs/xid"
)

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

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

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

// 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

// GetCellAt returns a reference to the cell at the given coordinates.
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"`
	// DisplayMode is the orientation and line parity used to display the map.
	DisplayMode HexMapRepresentation `json:"displayMode"`
	// LineCells contains the actual map data.
	// LineCells itself is a slice with Lines elements, each of which is a line;
	// each of those lines is a slice of CellsPerLine cells.
	LineCells HexLayer `json:"lineCells"`
}

// Copy creates a deep copy of this HexMap.
func (m HexMap) Copy() HexMap {
	return HexMap{
		Xid:          m.Xid,
		Lines:        m.Lines,
		CellsPerLine: m.CellsPerLine,
		DisplayMode:  m.DisplayMode,
		LineCells:    m.LineCells.Copy(),
	}
}