Feature: Show where file is being used on Commons & Other wikis (#6006)

* add url to build config

Signed-off-by: parneet-guraya <gurayaparneet@gmail.com>

* add network call functions

Signed-off-by: parneet-guraya <gurayaparneet@gmail.com>

* return response asynchronously

Signed-off-by: parneet-guraya <gurayaparneet@gmail.com>

* inject page size in the request

Signed-off-by: parneet-guraya <gurayaparneet@gmail.com>

* rename from Commons..Response.kt to ..Response.kt

Signed-off-by: parneet-guraya <gurayaparneet@gmail.com>

* convert to .kt

Signed-off-by: parneet-guraya <gurayaparneet@gmail.com>

* ui setup working

Signed-off-by: parneet-guraya <gurayaparneet@gmail.com>

* fix merge conflict

Signed-off-by: parneet-guraya <gurayaparneet@gmail.com>

* cleanup

Signed-off-by: parneet-guraya <gurayaparneet@gmail.com>

* fix CI

Signed-off-by: parneet-guraya <gurayaparneet@gmail.com>

* use suspend function for network calls

Signed-off-by: parneet-guraya <gurayaparneet@gmail.com>

* doc

* doc

* doc

* doc

* doc

---------

Signed-off-by: parneet-guraya <gurayaparneet@gmail.com>
Co-authored-by: Nicolas Raoul <nicolas.raoul@gmail.com>

app/src/main/java/fr/free/nrw/commons/media/MediaDetailViewModel.kt

@@ -0,0 +1,116 @@
+package fr.free.nrw.commons.media
+
+import android.content.Context
+import androidx.lifecycle.ViewModel
+import androidx.lifecycle.ViewModelProvider
+import androidx.lifecycle.viewModelScope
+import fr.free.nrw.commons.R
+import fr.free.nrw.commons.fileusages.FileUsagesUiModel
+import fr.free.nrw.commons.fileusages.toUiModel
+import fr.free.nrw.commons.mwapi.OkHttpJsonApiClient
+import kotlinx.coroutines.flow.MutableStateFlow
+import kotlinx.coroutines.flow.asStateFlow
+import kotlinx.coroutines.flow.update
+import kotlinx.coroutines.launch
+import timber.log.Timber
+import javax.inject.Inject
+
+/**
+ * Show where file is being used on Commons and oher wikis.
+ */
+class MediaDetailViewModel(
+    private val applicationContext: Context,
+    private val okHttpJsonApiClient: OkHttpJsonApiClient
+) :
+    ViewModel() {
+
+    private val _commonsContainerState =
+        MutableStateFlow<FileUsagesContainerState>(FileUsagesContainerState.Initial)
+    val commonsContainerState = _commonsContainerState.asStateFlow()
+
+    private val _globalContainerState =
+        MutableStateFlow<FileUsagesContainerState>(FileUsagesContainerState.Initial)
+    val globalContainerState = _globalContainerState.asStateFlow()
+
+    fun loadFileUsagesCommons(fileName: String) {
+
+        viewModelScope.launch {
+
+            _commonsContainerState.update { FileUsagesContainerState.Loading }
+
+            try {
+                val result =
+                    okHttpJsonApiClient.getFileUsagesOnCommons(fileName, 10)
+
+                val data = result?.query?.pages?.first()?.fileUsage?.map { it.toUiModel() }
+
+                _commonsContainerState.update { FileUsagesContainerState.Success(data = data) }
+
+            } catch (e: Exception) {
+
+                _commonsContainerState.update {
+                    FileUsagesContainerState.Error(
+                        errorMessage = applicationContext.getString(
+                            R.string.error_while_loading
+                        )
+                    )
+                }
+
+                Timber.e(e, javaClass.simpleName)
+
+            }
+        }
+
+    }
+
+    fun loadGlobalFileUsages(fileName: String) {
+
+        viewModelScope.launch {
+
+            _globalContainerState.update { FileUsagesContainerState.Loading }
+
+            try {
+                val result = okHttpJsonApiClient.getGlobalFileUsages(fileName, 10)
+
+                val data = result?.query?.pages?.first()?.fileUsage?.map { it.toUiModel() }
+
+                _globalContainerState.update { FileUsagesContainerState.Success(data = data) }
+
+            } catch (e: Exception) {
+                _globalContainerState.update {
+                    FileUsagesContainerState.Error(
+                        errorMessage = applicationContext.getString(
+                            R.string.error_while_loading
+                        )
+                    )
+                }
+
+                Timber.e(e, javaClass.simpleName)
+
+            }
+        }
+
+    }
+
+    sealed class FileUsagesContainerState {
+        object Initial : FileUsagesContainerState()
+        object Loading : FileUsagesContainerState()
+        data class Success(val data: List<FileUsagesUiModel>?) : FileUsagesContainerState()
+        data class Error(val errorMessage: String) : FileUsagesContainerState()
+    }
+
+    class MediaDetailViewModelProviderFactory
+    @Inject constructor(
+        private val okHttpJsonApiClient: OkHttpJsonApiClient,
+        private val applicationContext: Context
+    ) :
+        ViewModelProvider.Factory {
+        override fun <T : ViewModel> create(modelClass: Class<T>): T {
+            if (modelClass.isAssignableFrom(MediaDetailViewModel::class.java)) {
+                @Suppress("UNCHECKED_CAST")
+                return MediaDetailViewModel(applicationContext, okHttpJsonApiClient) as T
+            }
+            throw IllegalArgumentException("Unknown ViewModel class")
+        }
+    }
+}