Refactor KtorHttpClient for Gemini API interaction:

    - Introduce `GeminiApiService` for handling Gemini API requests.
    - Create `KtorClientProvider` to manage the Ktor `HttpClient` and `Json` instances.
    - Implement `GeminiPromptBuilder` to construct API request prompts and bodies.
    - Add `GeminiJsonParser` for extracting and cleaning JSON from API responses.
- Move data models `CodeExample`, `Section`, and `Syntax` to separate files.
- Remove unused OpenAI-related data classes from `KotlinTopicDetails.kt`.
- Update `DetailRepository` to use the new `GeminiApiService`.

Author: yesshreyes

composeApp/src/commonMain/kotlin/com/developersbreach/kotlindictionarymultiplatform/core/network/KtorHttpClient.kt

@@ -0,0 +1,38 @@
+package com.developersbreach.kotlindictionarymultiplatform.core.network.api
+
+import com.developersbreach.kotlindictionarymultiplatform.Log
+import com.developersbreach.kotlindictionarymultiplatform.core.network.client.KtorClientProvider
+import com.developersbreach.kotlindictionarymultiplatform.core.network.parser.GeminiJsonParser
+import com.developersbreach.kotlindictionarymultiplatform.core.network.request.GeminiPromptBuilder
+import com.developersbreach.kotlindictionarymultiplatform.data.detail.model.KotlinTopicDetails
+import io.ktor.client.request.post
+import io.ktor.client.request.setBody
+import io.ktor.client.statement.bodyAsText
+import io.ktor.http.ContentType
+import io.ktor.http.contentType
+
+object GeminiApiService {
+
+    suspend fun generateTopicDetails(
+        topicId: String,
+        apiKey: String,
+    ): KotlinTopicDetails {
+        val prompt = GeminiPromptBuilder.buildRequest(topicId)
+        val requestBody = GeminiPromptBuilder.buildRequestBody(prompt)
+
+        val response = KtorClientProvider.client.post(
+            "https://generativelanguage.googleapis.com/v1/models/gemini-2.0-flash:generateContent?key=$apiKey",
+        ) {
+            contentType(ContentType.Application.Json)
+            setBody(requestBody)
+        }
+
+        val responseBody = response.bodyAsText()
+        Log.i("GeminiRawResponse", responseBody)
+
+        val cleanJson = GeminiJsonParser.extractCleanJson(responseBody, KtorClientProvider.json)
+        Log.i("CleanJson", cleanJson)
+
+        return KtorClientProvider.json.decodeFromString(KotlinTopicDetails.serializer(), cleanJson)
+    }
+}

composeApp/src/commonMain/kotlin/com/developersbreach/kotlindictionarymultiplatform/core/network/api/GeminiApiService.kt

@@ -0,0 +1,20 @@
+package com.developersbreach.kotlindictionarymultiplatform.core.network.client
+
+import io.ktor.client.HttpClient
+import io.ktor.client.plugins.contentnegotiation.ContentNegotiation
+import io.ktor.serialization.kotlinx.json.json
+import kotlinx.serialization.json.Json
+
+object KtorClientProvider {
+
+    val json = Json {
+        ignoreUnknownKeys = true
+        prettyPrint = true
+    }
+
+    val client = HttpClient {
+        install(ContentNegotiation) {
+            json()
+        }
+    }
+}

composeApp/src/commonMain/kotlin/com/developersbreach/kotlindictionarymultiplatform/core/network/client/KtorClientProvider.kt

@@ -0,0 +1,32 @@
+package com.developersbreach.kotlindictionarymultiplatform.core.network.parser
+
+import kotlinx.serialization.json.Json
+import kotlinx.serialization.json.jsonObject
+import kotlinx.serialization.json.jsonArray
+import kotlinx.serialization.json.jsonPrimitive
+
+object GeminiJsonParser {
+
+    fun extractCleanJson(
+        rawResponse: String,
+        json: Json,
+    ): String {
+        val root = json.parseToJsonElement(rawResponse).jsonObject
+        val text = root["candidates"]
+            ?.jsonArray?.firstOrNull()
+            ?.jsonObject?.get("content")
+            ?.jsonObject?.get("parts")
+            ?.jsonArray?.firstOrNull()
+            ?.jsonObject?.get("text")
+            ?.jsonPrimitive?.content
+            ?: error("Malformed Gemini response")
+
+        return text
+            .removePrefix("```json\n")
+            .removePrefix("```json")
+            .removePrefix("json\n")
+            .removePrefix("json")
+            .removeSuffix("```")
+            .trim()
+    }
+}

composeApp/src/commonMain/kotlin/com/developersbreach/kotlindictionarymultiplatform/core/network/parser/GeminiJsonParser.kt

@@ -0,0 +1,95 @@
+package com.developersbreach.kotlindictionarymultiplatform.core.network.request
+
+import kotlinx.serialization.json.JsonObject
+import kotlinx.serialization.json.buildJsonObject
+import kotlinx.serialization.json.addJsonObject
+import kotlinx.serialization.json.put
+import kotlinx.serialization.json.putJsonArray
+
+object GeminiPromptBuilder {
+
+    private val jsonSchema = """
+        {
+          "type": "object",
+          "properties": {
+            "topicId": { "type": "string" },
+            "topicName": { "type": "string" },
+            "intro": { "type": "string" },
+            "syntax": {
+              "type": "object",
+              "properties": {
+                "signature": { "type": "string" },
+                "notes": { "type": "string" }
+              },
+              "required": ["signature"]
+            },
+            "sections": {
+              "type": "array",
+              "items": {
+                "type": "object",
+                "properties": {
+                  "heading": { "type": "string" },
+                  "content": { "type": "string" },
+                  "codeExamples": {
+                    "type": "array",
+                    "items": {
+                      "type": "object",
+                      "properties": {
+                        "description": { "type": "string" },
+                        "code": { "type": "string" },
+                        "language": { "type": "string" }
+                      },
+                      "required": ["code"]
+                    }
+                  }
+                },
+                "required": ["heading", "content"]
+              }
+            },
+            "pitfalls": { "type": "array", "items": { "type": "string" } },
+            "relatedTopics": { "type": "array", "items": { "type": "string" } },
+            "metadata": { "type": "object", "additionalProperties": true }
+          },
+          "required": ["topicId", "topicName", "intro", "syntax", "sections"]
+        }
+    """.trimIndent()
+
+    fun buildRequest(
+        topicId: String,
+    ): String {
+        return """
+        You are a Kotlin documentation generator.
+
+        Generate a detailed JSON object for the topic "$topicId". 
+        The output MUST strictly conform to the following JSON schema:
+
+        $jsonSchema
+
+        Requirements:
+        - Respond only with pure JSON.
+        - Do not include any Markdown formatting (no ```json).
+        - Ensure all required fields are present.
+        - Use valid Kotlin examples.
+        - Include at least 3 sections with headings, content, and code examples.
+        - Use the language "kotlin" in each code example.
+
+        Make sure the entire response is a **valid JSON** object matching the schema above.
+            """.trimIndent()
+    }
+
+    fun buildRequestBody(
+        prompt: String,
+    ): JsonObject {
+        return buildJsonObject {
+            putJsonArray("contents") {
+                addJsonObject {
+                    putJsonArray("parts") {
+                        addJsonObject {
+                            put("text", prompt)
+                        }
+                    }
+                }
+            }
+        }
+    }
+}

composeApp/src/commonMain/kotlin/com/developersbreach/kotlindictionarymultiplatform/core/network/request/GeminiPromptBuilder.kt

@@ -0,0 +1,10 @@
+package com.developersbreach.kotlindictionarymultiplatform.data.detail.model
+
+import kotlinx.serialization.Serializable
+
+@Serializable
+data class CodeExample(
+    val description: String? = null,
+    val code: String,
+    val language: String = "kotlin",
+)