From 3f1e3163bb86d0e700ff38a4500ae8b801cc002c Mon Sep 17 00:00:00 2001
From: madhead <siarhei.krukau@gmail.com>
Date: Mon, 18 Apr 2022 15:00:12 +0200
Subject: [PATCH] Parse today's posts

---
 gradle/libs.versions.toml                     |  2 +
 herald/build.gradle.kts                       | 11 +++++
 .../by/jprof/telegram/bot/herald/App.kt       | 11 ++++-
 .../by/jprof/telegram/bot/herald/impl/post.kt | 23 ++++++++++
 .../telegram/bot/herald/impl/postFile.kt      | 15 +++++++
 .../telegram/bot/herald/model/Frontmatter.kt  | 11 +++++
 .../jprof/telegram/bot/herald/model/Post.kt   |  6 +++
 .../telegram/bot/herald/impl/PostTest.kt      | 45 +++++++++++++++++++
 herald/src/test/resources/posts/001.md        |  7 +++
 herald/src/test/resources/posts/002.md        |  9 ++++
 10 files changed, 139 insertions(+), 1 deletion(-)
 create mode 100644 herald/src/main/kotlin/by/jprof/telegram/bot/herald/impl/post.kt
 create mode 100644 herald/src/main/kotlin/by/jprof/telegram/bot/herald/impl/postFile.kt
 create mode 100644 herald/src/main/kotlin/by/jprof/telegram/bot/herald/model/Frontmatter.kt
 create mode 100644 herald/src/main/kotlin/by/jprof/telegram/bot/herald/model/Post.kt
 create mode 100644 herald/src/test/kotlin/by/jprof/telegram/bot/herald/impl/PostTest.kt
 create mode 100644 herald/src/test/resources/posts/001.md
 create mode 100644 herald/src/test/resources/posts/002.md

diff --git a/gradle/libs.versions.toml b/gradle/libs.versions.toml
index 2ec6182a..3c181b1a 100644
--- a/gradle/libs.versions.toml
+++ b/gradle/libs.versions.toml
@@ -12,6 +12,7 @@ ktor = "1.6.8"
 
 kotlinx-serialization = "1.3.0"
 jackson = "2.13.0"
+kaml = "0.43.0"
 
 tgbotapi = "0.35.9"
 
@@ -45,6 +46,7 @@ ktor-client-serialization = { group = "io.ktor", name = "ktor-client-serializati
 kotlinx-serialization-core = { module = "org.jetbrains.kotlinx:kotlinx-serialization-core", version.ref = "kotlinx-serialization" }
 kotlinx-serialization-json = { module = "org.jetbrains.kotlinx:kotlinx-serialization-json", version.ref = "kotlinx-serialization" }
 jackson-databind = { group = "com.fasterxml.jackson.core", name = "jackson-databind", version.ref = "jackson" }
+kaml = { group = "com.charleskorn.kaml", name = "kaml", version.ref = "kaml" }
 
 tgbotapi-core = { group = "dev.inmo", name = "tgbotapi.core", version.ref = "tgbotapi" }
 tgbotapi-extensions-api = { group = "dev.inmo", name = "tgbotapi.extensions.api", version.ref = "tgbotapi" }
diff --git a/herald/build.gradle.kts b/herald/build.gradle.kts
index 9f40d1fe..ca71e9de 100644
--- a/herald/build.gradle.kts
+++ b/herald/build.gradle.kts
@@ -1,8 +1,19 @@
 plugins {
     kotlin("jvm")
+    kotlin("plugin.serialization")
     application
 }
 
 application {
     mainClass.set("by.jprof.telegram.bot.herald.AppKt")
 }
+
+dependencies {
+    implementation(libs.kotlinx.serialization.core)
+    implementation(libs.kaml)
+
+    testImplementation(libs.junit.jupiter.api)
+    testImplementation(libs.junit.jupiter.params)
+    testRuntimeOnly(libs.junit.jupiter.engine)
+    testRuntimeOnly(libs.log4j.core)
+}
diff --git a/herald/src/main/kotlin/by/jprof/telegram/bot/herald/App.kt b/herald/src/main/kotlin/by/jprof/telegram/bot/herald/App.kt
index f9ab0277..d9efed6c 100644
--- a/herald/src/main/kotlin/by/jprof/telegram/bot/herald/App.kt
+++ b/herald/src/main/kotlin/by/jprof/telegram/bot/herald/App.kt
@@ -1,5 +1,14 @@
 package by.jprof.telegram.bot.herald
 
+import by.jprof.telegram.bot.herald.impl.post
+import by.jprof.telegram.bot.herald.impl.postFile
+
 suspend fun main(args: Array<String>) {
-    println("Hello, world!")
+    val postFile = postFile() ?: run { println("No post for today"); return }
+
+    println("Today's post: $postFile")
+
+    val post = post(postFile) ?: run { println("Cannot parse the file"); return }
+
+    println("Parsed the post: $post")
 }
diff --git a/herald/src/main/kotlin/by/jprof/telegram/bot/herald/impl/post.kt b/herald/src/main/kotlin/by/jprof/telegram/bot/herald/impl/post.kt
new file mode 100644
index 00000000..ad495cbf
--- /dev/null
+++ b/herald/src/main/kotlin/by/jprof/telegram/bot/herald/impl/post.kt
@@ -0,0 +1,23 @@
+package by.jprof.telegram.bot.herald.impl
+
+import by.jprof.telegram.bot.herald.model.Post
+import com.charleskorn.kaml.Yaml
+import kotlinx.serialization.decodeFromString
+import java.nio.file.Path
+import kotlin.io.path.readText
+import kotlin.text.RegexOption.DOT_MATCHES_ALL
+import kotlin.text.RegexOption.MULTILINE
+
+fun post(path: Path): Post? {
+    val text = path.readText()
+    val regex = Regex("-{3,}\\R(?<frontmatter>.*)\\R-{3,}\\s+(?<content>.*)", setOf(MULTILINE, DOT_MATCHES_ALL))
+
+    return regex.find(text)?.let {
+        val groups = it.groups as MatchNamedGroupCollection
+
+        val frontmatter = groups["frontmatter"]?.value ?: return null
+        val content = groups["content"]?.value ?: return null
+
+        Post(Yaml.default.decodeFromString(frontmatter), content)
+    }
+}
diff --git a/herald/src/main/kotlin/by/jprof/telegram/bot/herald/impl/postFile.kt b/herald/src/main/kotlin/by/jprof/telegram/bot/herald/impl/postFile.kt
new file mode 100644
index 00000000..35a9e0e2
--- /dev/null
+++ b/herald/src/main/kotlin/by/jprof/telegram/bot/herald/impl/postFile.kt
@@ -0,0 +1,15 @@
+package by.jprof.telegram.bot.herald.impl
+
+import java.nio.file.Path
+import java.time.LocalDate
+import java.time.format.DateTimeFormatter
+import kotlin.io.path.Path
+import kotlin.io.path.exists
+
+fun postFile(): Path? {
+    val cwd = Path("")
+    val today = LocalDate.now()
+    val formatter = DateTimeFormatter.ofPattern("yyyy/MM/dd")
+
+    return cwd.resolve(today.format(formatter) + ".md").takeIf { it.exists() }
+}
diff --git a/herald/src/main/kotlin/by/jprof/telegram/bot/herald/model/Frontmatter.kt b/herald/src/main/kotlin/by/jprof/telegram/bot/herald/model/Frontmatter.kt
new file mode 100644
index 00000000..d3ae91a5
--- /dev/null
+++ b/herald/src/main/kotlin/by/jprof/telegram/bot/herald/model/Frontmatter.kt
@@ -0,0 +1,11 @@
+package by.jprof.telegram.bot.herald.model
+
+import kotlinx.serialization.Serializable
+
+@Serializable
+data class Frontmatter(
+    val chats: List<Long>,
+    val image: String? = null,
+    val disableWebPagePreview: Boolean = false,
+    val votes: List<String>? = null,
+)
diff --git a/herald/src/main/kotlin/by/jprof/telegram/bot/herald/model/Post.kt b/herald/src/main/kotlin/by/jprof/telegram/bot/herald/model/Post.kt
new file mode 100644
index 00000000..1ae1ee69
--- /dev/null
+++ b/herald/src/main/kotlin/by/jprof/telegram/bot/herald/model/Post.kt
@@ -0,0 +1,6 @@
+package by.jprof.telegram.bot.herald.model
+
+data class Post(
+    val frontmatter: Frontmatter,
+    val content: String,
+)
diff --git a/herald/src/test/kotlin/by/jprof/telegram/bot/herald/impl/PostTest.kt b/herald/src/test/kotlin/by/jprof/telegram/bot/herald/impl/PostTest.kt
new file mode 100644
index 00000000..1a342645
--- /dev/null
+++ b/herald/src/test/kotlin/by/jprof/telegram/bot/herald/impl/PostTest.kt
@@ -0,0 +1,45 @@
+package by.jprof.telegram.bot.herald.impl
+
+import by.jprof.telegram.bot.herald.model.Frontmatter
+import by.jprof.telegram.bot.herald.model.Post
+import org.junit.jupiter.api.Assertions.assertEquals
+import org.junit.jupiter.api.Named
+import org.junit.jupiter.params.ParameterizedTest
+import org.junit.jupiter.params.provider.Arguments
+import org.junit.jupiter.params.provider.MethodSource
+import java.nio.file.Path
+import java.util.stream.Stream
+
+internal class PostTest {
+    @ParameterizedTest(name = "{0}")
+    @MethodSource
+    fun post(path: Path, post: Post) {
+        assertEquals(
+            post,
+            post(path)
+        )
+    }
+
+    companion object {
+        @JvmStatic
+        fun post() = Stream.of(
+            Arguments.of(
+                Named.of("001", "001".testResourcePath),
+                Post(
+                    Frontmatter(chats = listOf(-1001146107319, -1001585354456)),
+                    "This is content.\n"
+                )
+            ),
+            Arguments.of(
+                Named.of("002", "002".testResourcePath),
+                Post(
+                    Frontmatter(chats = listOf(-1001146107319, -1001585354456), image = "002.png"),
+                    "This is a\nmultiline content!\n"
+                )
+            ),
+        )
+
+        private val String.testResourcePath: Path
+            get() = Path.of(this@Companion::class.java.classLoader.getResource("posts/$this.md").toURI())
+    }
+}
diff --git a/herald/src/test/resources/posts/001.md b/herald/src/test/resources/posts/001.md
new file mode 100644
index 00000000..db1381a2
--- /dev/null
+++ b/herald/src/test/resources/posts/001.md
@@ -0,0 +1,7 @@
+---
+chats:
+  - -1001146107319 # JPROF.BY
+  - -1001585354456 # JPROF.PL
+---
+
+This is content.
diff --git a/herald/src/test/resources/posts/002.md b/herald/src/test/resources/posts/002.md
new file mode 100644
index 00000000..b1e4daa6
--- /dev/null
+++ b/herald/src/test/resources/posts/002.md
@@ -0,0 +1,9 @@
+---
+chats:
+  - -1001146107319 # JPROF.BY
+  - -1001585354456 # JPROF.PL
+image: 002.png
+---
+
+This is a
+multiline content!