recipe-kt/app/src/main/java/xyz/pixelatedw/recipe/utils/RecipeParser.kt

package xyz.pixelatedw.recipe.utils

import android.content.Context
import android.graphics.Bitmap
import android.graphics.BitmapFactory
import android.net.Uri
import androidx.core.text.trimmedLength
import androidx.documentfile.provider.DocumentFile
import io.github.wasabithumb.jtoml.JToml
import xyz.pixelatedw.recipe.data.Recipe
import xyz.pixelatedw.recipe.data.RecipesView
import java.io.BufferedReader
import java.io.InputStreamReader

private val previews = HashMap<String, Bitmap>()
private val recipeFiles = mutableListOf<DocumentFile>()

fun getRecipes(ctx: Context, view: RecipesView, uri: Uri?) {
	if (uri == null) {
		return
	}

	val dir = DocumentFile.fromTreeUri(ctx, uri)
	if (dir != null) {
		parseDir(ctx, dir)

		for (file in recipeFiles) {
			val recipe = parseRecipe(ctx, file)
			if (recipe != null) {
				view.addRecipe(recipe)
			}
		}
	}
}

fun parseDir(ctx: Context, dir: DocumentFile) {
	val fileList: Array<DocumentFile> = dir.listFiles()
	for (file in fileList) {
		if(file.isDirectory) {
			parseDir(ctx, file)
			continue;
		}

		if (file.isFile && file.name?.endsWith(".jpg") == true) {
			val inStream = ctx.contentResolver.openInputStream(file.uri)

			var bitmap: Bitmap? = null
			if (file.exists()) {
				try {
					bitmap = BitmapFactory.decodeStream(inStream)
				}
				finally {
				    inStream?.close()
				}
			}

			if (bitmap != null) {
				previews[file.name!!] = bitmap
			}
		}
		if (file.isFile && file.name?.endsWith(".md") == true) {
			recipeFiles.add(file)
		}
	}
}

private fun parseRecipe(ctx: Context, file: DocumentFile): Recipe? {
	val lastModified = file.lastModified()

	val inputStream = ctx.contentResolver.openInputStream(file.uri)
	val reader = BufferedReader(InputStreamReader(inputStream))
	val text = reader.readText()
	val lines = text.lines()

	val sb = StringBuilder()
	var hasToml = false
	var frontMatterSize = 0
	// TODO This could use some improvements as it always assumes frontmatter is the very first thing in the file
	for (i in 0..lines.size) {
		val line = lines[i]
		frontMatterSize += line.trimmedLength() + 1

		if (line == "+++") {
			if (hasToml) {
				break
			}
			hasToml = true
			continue
		}

		sb.appendLine(line)
	}

	val toml = JToml.jToml()
	val doc = toml.readFromString(sb.toString())

	val tags = arrayListOf<String>()
	for (tomlElem in doc["tags"]!!.asArray()) {
		tags.add(tomlElem!!.asPrimitive().asString())
	}

	val pics = arrayListOf<String>()
	for (tomlElem in doc["pics"]!!.asArray()) {
		pics.add(tomlElem!!.asPrimitive().asString())
	}

	val recipePreviews = mutableListOf<Bitmap>()
	for (pic in pics) {
		val bitmap = previews[pic]
		if (bitmap != null) {
			recipePreviews.add(bitmap)
		}
	}

	val content = text.substring(frontMatterSize..<text.length)

	val recipe = Recipe(
		title = doc["title"]!!.asPrimitive().asString(),
		tags = tags,
		previews = recipePreviews,
		lastModified = lastModified,
		content = content
	)

	reader.close()

	return recipe
}