import * as path from "@std/path"
import "zx/globals"
import { colordx, type OklchColor } from "@colordx/core"

export interface AnalysisConfig {
	imageDir: string
	preAnalysisCommands: string[]
}

export interface ImageAnalysisData {
	files: { path: string; colour: OklchColor }[]
}

export const defaultConfig: AnalysisConfig = {
	imageDir: path.fromFileUrl(`file:///${os.homedir()}/Pictures`),
	preAnalysisCommands: [],
}

export async function runPreAnalysis(hooks: string[]) {
	for await (const hook of hooks) {
		await $`eval ${hook}` // Scary!
	}
}

export async function analyzeImages(imageDir: string, analysisOutput: ImageAnalysisData, outputPath: string) {
	const images = await fs.promises.opendir(imageDir)

	for await (const image of images) {
		const imagePath = path.join(imageDir, image.name)
		const stat = await fs.promises.stat(imagePath)
		if (stat.isFile()) {
			try {
				let output = await $`magick ${imagePath} -colorspace Oklch -kmeans 10 -format "%c" histogram:info:`
					.then(
						(s) =>
							s.stdout
								.split("\n")
								.map((substr) => substr.trim())
								.filter((n) => n),
					) as string[]

				if (output.length < 5) {
					// do it again but with more violence
					console.log(
						`-kmeans 10 of ${image.name} didn't give enough colours, trying again with a higher value...`,
					)
					output = await $`magick ${imagePath} -colorspace Oklch -kmeans 40 -format "%c" histogram:info:`
						.then(
							(s) =>
								s.stdout
									.split("\n") // split the output by newlines
									.map((substr) => substr.trim()) // trim the whitespace on each line
									.filter((n) => n), // and then filter out any blank elements generated
						)
				}
				const colours = output.map((entry) => {
					const arr = entry.split(" ")
					arr.pop()
					// [# of pixels, oklab colour, hex code]
					return {
						pixels: parseInt(arr[0]),
						oklab: arr[1].replace(/[()]/g, "").split(","), // (0,0,0) -> Array [0, 0, 0]
						hex: arr[2],
					}
				})

				colours.sort((a, b) => (b.pixels) - (a.pixels))

				const dominantColour = colordx({
					l: Number(colours[0].oklab[0]),
					c: Number(colours[0].oklab[1]),
					h: Number(colours[0].oklab[2]),
				})

				analysisOutput.files.push({ path: imagePath, colour: dominantColour.toOklch() })

				console.log(
					`Got ${dominantColour.toOklchString()} as dominant colour of ${image.name}!`,
				)

				// flush every time we finish analyzing a file, because it just takes so long
				fs.writeFile(outputPath, JSON.stringify(analysisOutput, null, 4), (err: Error) => {
					if (err) throw new Error(err.message)
				})
			} catch (e) {
				console.warn(`Got error ${e} when attempting to analyze ${imagePath}! Continuing...`)
			}
		}
	}
}