Support custom problem list

app/src/main/assets/list/blind_75.json

@@ -0,0 +1,85 @@
+[
+  "Two Sum",
+  "Longest Substring Without Repeating Characters",
+  "Longest Palindromic Substring",
+  "Container With Most Water",
+  "3Sum",
+  "Remove Nth Node From End of List",
+  "Valid Parentheses",
+  "Merge Two Sorted Lists",
+  "Merge k Sorted Lists",
+  "Search in Rotated Sorted Array",
+  "Combination Sum",
+  "Group Anagrams",
+  "Maximum Subarray",
+  "Jump Game",
+  "Merge Intervals",
+  "Insert Interval",
+  "Unique Paths",
+  "Climbing Stairs",
+  "Set Matrix Zeroes",
+  "Search a 2D Matrix",
+  "Minimum Window Substring",
+  "Subsets",
+  "Word Search",
+  "Decode Ways",
+  "Validate Binary Search Tree",
+  "Same Tree",
+  "Binary Tree Level Order Traversal",
+  "Maximum Depth of Binary Tree",
+  "Construct Binary Tree from Preorder and Inorder Traversal",
+  "Best Time to Buy and Sell Stock",
+  "Binary Tree Maximum Path Sum",
+  "Valid Palindrome",
+  "Word Break",
+  "Linked List Cycle",
+  "Reorder List",
+  "Maximum Product Subarray",
+  "Find Minimum in Rotated Sorted Array",
+  "Reverse Bits",
+  "Number of 1 Bits",
+  "House Robber",
+  "Number of Islands",
+  "Reverse Linked List",
+  "Course Schedule",
+  "Implement Trie (Prefix Tree)",
+  "Design Add and Search Words Data Structure",
+  "Word Search II",
+  "House Robber II",
+  "Contains Duplicate",
+  "Invert Binary Tree",
+  "Kth Smallest Element in a BST",
+  "Lowest Common Ancestor of a Binary Search Tree",
+  "Lowest Common Ancestor of a Binary Tree",
+  "Product of Array Except Self",
+  "Valid Anagram",
+  "Meeting Rooms",
+  "Meeting Rooms II",
+  "Graph Valid Tree",
+  "Missing Number",
+  "Alien Dictionary",
+  "Encode and Decode Strings",
+  "Find Median from Data Stream",
+  "Longest Increasing Subsequence",
+  "Coin Change",
+  "Sum of Two Integers",
+  "Counting Bits",
+  "Longest Common Subsequence",
+  "Word Break Problem",
+  "Clone Graph",
+  "Pacific Atlantic Water Flow",
+  "Longest Consecutive Sequence",
+  "Number of Connected Components in an Undirected Graph",
+  "Non-overlapping Intervals",
+  "Reverse a Linked List",
+  "Detect Cycle in a Linked List",
+  "Spiral Matrix",
+  "Rotate Image",
+  "Longest Repeating Character Replacement",
+  "Palindromic Substrings",
+  "Invert/Flip Binary Tree",
+  "Serialize and Deserialize Binary Tree",
+  "Subtree of Another Tree",
+  "Lowest Common Ancestor of BST",
+  "Top K Frequent Elements"
+]

app/src/main/assets/predefined_problem_set_manifest.json

@@ -0,0 +1,7 @@
+[
+  {
+    "id": "blind_75",
+    "name": "Blind 75",
+    "file": "blind_75.json"
+  }
+]

app/src/main/kotlin/com/byteutility/dev/leetcode/plus/data/repository/di/FactoryModule.kt

@@ -0,0 +1,41 @@
+package com.byteutility.dev.leetcode.plus.data.repository.di
+
+import android.content.Context
+import android.content.res.AssetManager
+import com.byteutility.dev.leetcode.plus.data.sets.AssetProblemSetFactory
+import com.byteutility.dev.leetcode.plus.data.sets.ProblemSetFactory
+import com.google.gson.Gson
+import com.google.gson.GsonBuilder
+import dagger.Module
+import dagger.Provides
+import dagger.hilt.InstallIn
+import dagger.hilt.android.qualifiers.ApplicationContext
+import dagger.hilt.components.SingletonComponent
+import javax.inject.Singleton
+
+@Module
+@InstallIn(SingletonComponent::class)
+object FactoryModule {
+
+    @Provides
+    @Singleton
+    fun provideGson(): Gson {
+        return GsonBuilder()
+            .create()
+    }
+
+    @Provides
+    @Singleton
+    fun provideAssetManager(@ApplicationContext context: Context): AssetManager {
+        return context.assets
+    }
+
+    @Provides
+    @Singleton
+    fun provideProblemSetFactory(
+        assetManager: AssetManager,
+        gson: Gson
+    ): ProblemSetFactory {
+        return AssetProblemSetFactory(assetManager, gson)
+    }
+}

app/src/main/kotlin/com/byteutility/dev/leetcode/plus/data/repository/problems/ProblemsRepository.kt

@@ -1,9 +1,10 @@
 package com.byteutility.dev.leetcode.plus.data.repository.problems
 
 import com.byteutility.dev.leetcode.plus.data.model.LeetCodeProblem
+import com.byteutility.dev.leetcode.plus.domain.model.ProblemSetType
 import com.byteutility.dev.leetcode.plus.network.responseVo.LeetCodeQuestionResponse
 
 interface ProblemsRepository {
-    suspend fun getProblems(limit: Long): List<LeetCodeProblem>
+    suspend fun getProblems(type: ProblemSetType? = null): List<LeetCodeProblem>
     suspend fun getSelectedRawQuestion(titleSlug: String): LeetCodeQuestionResponse
 }

app/src/main/kotlin/com/byteutility/dev/leetcode/plus/data/repository/problems/ProblemsRepositoryImpl.kt

@@ -1,54 +1,35 @@
 package com.byteutility.dev.leetcode.plus.data.repository.problems
 
-import android.content.Context
 import com.byteutility.dev.leetcode.plus.data.model.LeetCodeProblem
+import com.byteutility.dev.leetcode.plus.data.sets.ProblemSet
+import com.byteutility.dev.leetcode.plus.data.sets.ProblemSetFactory
+import com.byteutility.dev.leetcode.plus.domain.model.ProblemSetType
 import com.byteutility.dev.leetcode.plus.network.RestApiService
 import com.byteutility.dev.leetcode.plus.network.responseVo.LeetCodeQuestionResponse
-import com.byteutility.dev.leetcode.plus.network.responseVo.ProblemSetResponseVo
-import com.google.gson.Gson
-import dagger.hilt.android.qualifiers.ApplicationContext
 import kotlinx.coroutines.Dispatchers
 import kotlinx.coroutines.withContext
 import javax.inject.Inject
 
 class ProblemsRepositoryImpl @Inject constructor(
-    @ApplicationContext private val context: Context,
+    private val factory: ProblemSetFactory,
     private val restApiService: RestApiService
 ) : ProblemsRepository {
 
+    private val masterList: List<LeetCodeProblem> by lazy {
+        factory.loadMasterList()
+    }
+    private val setCache = mutableMapOf<ProblemSetType, ProblemSet>()
+
     override suspend fun getProblems(
-        limit: Long
+        type: ProblemSetType?
     ): List<LeetCodeProblem> {
-        var leetCodeProblems: List<LeetCodeProblem> = mutableListOf()
-        withContext(Dispatchers.IO) {
-            val response: ProblemSetResponseVo = parseProblemsJson(context)
-            response.problemSetQuestionList.map {
-                LeetCodeProblem(
-                    title = it.title,
-                    difficulty = it.difficulty,
-                    tag = it.topicTags.firstOrNull()?.name ?: "NO_TAG",
-                    titleSlug = it.titleSlug,
-                )
-            }.run {
-                leetCodeProblems = this
+        return withContext(Dispatchers.IO) {
+            if (type == null) return@withContext masterList
+            val problemSet = setCache.getOrPut(type) {
+                factory.createSet(type)
             }
+            masterList.filter { problemSet.isIncluded(it) }
         }
-        return leetCodeProblems
-    }
-
-    private fun parseProblemsJson(
-        context: Context
-    ): ProblemSetResponseVo {
-        val jsonString = loadJsonFromAssets(context, "problems.json")
-        val gson = Gson()
-        return gson.fromJson(jsonString, ProblemSetResponseVo::class.java)
-    }
-
-    private fun loadJsonFromAssets(
-        context: Context,
-        fileName: String
-    ): String {
-        return context.assets.open(fileName).bufferedReader().use { it.readText() }
     }
 
     @Throws

app/src/main/kotlin/com/byteutility/dev/leetcode/plus/data/repository/problems/predefined/PredefinedProblemSetMetadataProvider.kt

@@ -0,0 +1,30 @@
+package com.byteutility.dev.leetcode.plus.data.repository.problems.predefined
+
+import android.content.res.AssetManager
+import android.util.Log
+import com.byteutility.dev.leetcode.plus.domain.model.SetMetadata
+import com.google.gson.Gson
+import com.google.gson.reflect.TypeToken
+import java.io.IOException
+import javax.inject.Inject
+
+class PredefinedProblemSetMetadataProvider @Inject constructor(
+    private val assetManager: AssetManager,
+    private val gson: Gson
+) {
+
+    fun getAvailableStaticSets(): List<SetMetadata> {
+        return try {
+            assetManager.open("predefined_problem_set_manifest.json").bufferedReader()
+                .use { reader ->
+                    val type = object : TypeToken<List<SetMetadata>>() {}.type
+                    gson.fromJson(reader, type)
+                }
+        } catch (e: IOException) {
+            Log.e(this.javaClass.name, "getAvailableStaticSets: exception ${e.message}")
+            emptyList()
+        } finally {
+            emptyList<SetMetadata>()
+        }
+    }
+}

app/src/main/kotlin/com/byteutility/dev/leetcode/plus/data/sets/AssetProblemSetFactory.kt

@@ -0,0 +1,56 @@
+package com.byteutility.dev.leetcode.plus.data.sets
+
+import android.content.res.AssetManager
+import com.byteutility.dev.leetcode.plus.data.model.LeetCodeProblem
+import com.byteutility.dev.leetcode.plus.domain.model.ProblemSetType
+import com.byteutility.dev.leetcode.plus.domain.model.ProblemSetType.PredefinedProblemSet
+import com.byteutility.dev.leetcode.plus.domain.model.ProblemSetType.UserDefinedProblemSet
+import com.byteutility.dev.leetcode.plus.network.responseVo.ProblemSetResponseVo
+import com.google.gson.Gson
+import com.google.gson.reflect.TypeToken
+import javax.inject.Inject
+
+class AssetProblemSetFactory @Inject constructor(
+    private val assetManager: AssetManager,
+    private val gson: Gson
+) : ProblemSetFactory {
+    override fun createSet(type: ProblemSetType): ProblemSet {
+        return when (type) {
+            is PredefinedProblemSet -> {
+                val titles = loadTitlesFromAssets(type.metadata.file)
+                PredefinedProblemSet(displayName = type.displayName, titles = titles)
+            }
+
+            is UserDefinedProblemSet -> {
+                UserDefinedProblemSet(
+                    displayName = type.displayName,
+                    titles = emptyList()
+                )
+            }
+        }
+    }
+
+    override fun loadMasterList(): List<LeetCodeProblem> {
+        return loadAllProblemFromAssets("problems.json").toList()
+    }
+
+    private fun loadTitlesFromAssets(fileName: String): List<String> {
+        val json = assetManager.open("list/$fileName").bufferedReader().use { it.readText() }
+        val listType = object : TypeToken<List<String>>() {}.type
+        return gson.fromJson<List<String>>(json, listType)
+    }
+
+    private fun loadAllProblemFromAssets(fileName: String): List<LeetCodeProblem> {
+        val json = assetManager.open(fileName).bufferedReader().use { it.readText() }
+        val response = gson.fromJson(json, ProblemSetResponseVo::class.java)
+        val allProblems = response.problemSetQuestionList.map {
+            LeetCodeProblem(
+                title = it.title,
+                difficulty = it.difficulty,
+                tag = it.topicTags.firstOrNull()?.name ?: "NO_TAG",
+                titleSlug = it.titleSlug,
+            )
+        }
+        return allProblems
+    }
+}

app/src/main/kotlin/com/byteutility/dev/leetcode/plus/data/sets/ProblemSet.kt

@@ -0,0 +1,31 @@
+package com.byteutility.dev.leetcode.plus.data.sets
+
+import com.byteutility.dev.leetcode.plus.data.model.LeetCodeProblem
+
+interface ProblemSet {
+    val displayName: String
+
+    /**
+     * Returns true if the given problem belongs to this specific set.
+     */
+    fun isIncluded(problem: LeetCodeProblem): Boolean
+}
+
+class PredefinedProblemSet(
+    override val displayName: String,
+    private val titles: List<String>
+) : ProblemSet {
+
+    override fun isIncluded(problem: LeetCodeProblem): Boolean {
+        return titles.contains(problem.title.trim())
+    }
+}
+
+class UserDefinedProblemSet(
+    override val displayName: String,
+    private val titles: List<String>
+) : ProblemSet {
+    override fun isIncluded(problem: LeetCodeProblem): Boolean {
+        return titles.contains(problem.title)
+    }
+}

app/src/main/kotlin/com/byteutility/dev/leetcode/plus/data/sets/ProblemSetFactory.kt

@@ -0,0 +1,9 @@
+package com.byteutility.dev.leetcode.plus.data.sets
+
+import com.byteutility.dev.leetcode.plus.data.model.LeetCodeProblem
+import com.byteutility.dev.leetcode.plus.domain.model.ProblemSetType
+
+interface ProblemSetFactory {
+    fun createSet(type: ProblemSetType): ProblemSet
+    fun loadMasterList(): List<LeetCodeProblem>
+}

app/src/main/kotlin/com/byteutility/dev/leetcode/plus/domain/model/ProblemSetType.kt

@@ -0,0 +1,14 @@
+package com.byteutility.dev.leetcode.plus.domain.model
+
+sealed interface ProblemSetType {
+    val displayName: String
+
+    data class PredefinedProblemSet(val metadata: SetMetadata) : ProblemSetType {
+        override val displayName: String = metadata.name
+    }
+
+    data class UserDefinedProblemSet(
+        override val displayName: String,
+        val fileName: String,
+    ) : ProblemSetType
+}

app/src/main/kotlin/com/byteutility/dev/leetcode/plus/domain/model/SetMetadata.kt

@@ -0,0 +1,3 @@
+package com.byteutility.dev.leetcode.plus.domain.model
+
+data class SetMetadata(val id: String, val name: String, val file: String)

app/src/main/kotlin/com/byteutility/dev/leetcode/plus/ui/navigation/LeetCodePlusNavGraph.kt

@@ -9,13 +9,13 @@ import androidx.navigation.compose.rememberNavController
 import androidx.navigation.toRoute
 import com.byteutility.dev.leetcode.plus.troubleshoot.TroubleShootScreen
 import com.byteutility.dev.leetcode.plus.ui.screens.MainScreen
+import com.byteutility.dev.leetcode.plus.ui.screens.contest.details.ContestDetailScreen
 import com.byteutility.dev.leetcode.plus.ui.screens.leetcodelogin.LeetCodeLoginWebView
 import com.byteutility.dev.leetcode.plus.ui.screens.login.UserLoginScreen
 import com.byteutility.dev.leetcode.plus.ui.screens.problem.details.ProblemDetailsScreen
 import com.byteutility.dev.leetcode.plus.ui.screens.solutions.VideoSolutionsScreen
 import com.byteutility.dev.leetcode.plus.ui.screens.targetset.SetWeeklyTargetScreen
 import com.byteutility.dev.leetcode.plus.ui.screens.targetstatus.GoalProgressScreen
-import com.byteutility.dev.leetcode.plus.ui.screens.contest.details.ContestDetailScreen
 import com.byteutility.dev.leetcode.plus.ui.screens.webview.CommonWebViewScreen
 
 @Composable