// Copyright 2020 Google Inc.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//      http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

// Package axes calculates the required layout and draws the X and Y axes of a heat map.
package axes

import (
	"errors"
	"image"

	"github.com/mum4k/termdash/private/runewidth"
)

const AxisWidth = 1

// YDetails contain information about the Y axis
// that will NOT be drawn onto the canvas, but will take up space.
type YDetails struct {
	// Width in character cells of the Y axis and its character labels.
	Width int

	// Start is the point where the Y axis starts.
	// The Y coordinate of Start is less than the Y coordinate of End.
	Start image.Point

	// End is the point where the Y axis ends.
	End image.Point

	// Labels are the labels for values on the Y axis in an increasing order.
	Labels []*Label
}

// RequiredWidth calculates the minimum width required
// in order to draw the Y axis and its labels.
// The parameter ls is the longest string in yLabels.
func RequiredWidth(ls string) int {
	return runewidth.StringWidth(ls) + AxisWidth
}

// NewYDetails retrieves details about the Y axis required
// to draw it on a canvas of the provided area.
func NewYDetails(labels []string) (*YDetails, error) {
	return nil, errors.New("not implemented")
}

// LongestString returns the length of the longest string in the string array.
func LongestString(strings []string) int {
	var widest int
	for _, s := range strings {
		if l := runewidth.StringWidth(s); l > widest {
			widest = l
		}
	}
	return widest
}

// XDetails contain information about the X axis
// that will NOT be drawn onto the canvas.
type XDetails struct {
	// Start is the point where the X axis starts.
	// Both coordinates of Start are less than End.
	Start image.Point
	// End is the point where the X axis ends.
	End image.Point

	// Labels are the labels for values on the X axis in an increasing order.
	Labels []*Label
}

// NewXDetails retrieves details about the X axis required to draw it on a canvas
// of the provided area.
// The yEnd is the point where the Y axis ends.
func NewXDetails(cvsAr image.Rectangle, yEnd image.Point, labels []string, cellWidth int) (*XDetails, error) {
	return nil, errors.New("not implemented")
}