1 files changed, 290 insertions, 0 deletions
diff --git a/src/github.c b/src/github.c
new file mode 100644
index 0000000..18bd992
--- /dev/null
+++ b/src/github.c
@@ -0,0 +1,290 @@
+//
+// Created by Anshul Gupta on 4/4/25.
+//
+
+#include "github.h"
+
+#include <stddef.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include <cJSON.h>
+#include <curl/curl.h>
+
+#include "queries/identity.h"
+#include "queries/list_repos.h"
+
+#include "buffer.h"
+#include "github_types.h"
+
+struct gh_impl {
+	struct github_ctx ctx;
+	CURL *curl;
+};
+
+static CURLcode gh_impl_send(const struct gh_impl *client, const char *query,
+			     cJSON *args, buffer_t *buf);
+
+static int gh_handle_error(const cJSON *root);
+
+github_client *github_client_new(const struct github_ctx ctx)
+{
+	struct gh_impl *c = malloc(sizeof(*c));
+	if (!c)
+		return NULL;
+
+	c->ctx.endpoint = strdup(ctx.endpoint);
+	c->ctx.token = strdup(ctx.token);
+	c->ctx.user_agent = strdup(ctx.user_agent);
+	c->curl = curl_easy_init();
+	return c;
+}
+
+github_client *github_client_dup(github_client *client)
+{
+	struct gh_impl *c = client;
+	if (!c)
+		return NULL;
+
+	struct gh_impl *dup = malloc(sizeof(*dup));
+	if (!dup)
+		return NULL;
+
+	dup->ctx.endpoint = strdup(c->ctx.endpoint);
+	dup->ctx.token = strdup(c->ctx.token);
+	dup->ctx.user_agent = strdup(c->ctx.user_agent);
+	dup->curl = curl_easy_duphandle(c->curl);
+
+	return dup;
+}
+
+void github_client_free(github_client *client)
+{
+	struct gh_impl *c = client;
+	if (!c)
+		return;
+	curl_easy_cleanup(c->curl);
+	free((char *) c->ctx.endpoint);
+	free((char *) c->ctx.token);
+	free((char *) c->ctx.user_agent);
+	free(c);
+}
+
+char *github_client_identity(const github_client *client)
+{
+	char *login = NULL;
+	const struct gh_impl *c = client;
+	buffer_t buf = buffer_new(4096);
+
+	const CURLcode ret = gh_impl_send(c, identity, NULL, &buf);
+	if (ret != CURLE_OK) {
+		fprintf(stderr, "Failed to send request: %s\n",
+			curl_easy_strerror(ret));
+		goto fail;
+	}
+
+	// Parse the response
+	cJSON *root = cJSON_Parse((const char *) buf.data);
+	if (!root) {
+		const char *err = cJSON_GetErrorPtr();
+		if (err)
+			fprintf(stderr, "Error parsing response: %s\n", err);
+		goto fail;
+	}
+
+	// Check for errors
+	if (gh_handle_error(root) < 0)
+		goto fail1;
+
+	// Get login from json
+	login = identity_from_json(root);
+
+fail1:
+	cJSON_Delete(root);
+fail:
+	buffer_free(buf);
+	return login;
+}
+
+int github_client_list_user_repos(const github_client *client,
+				  const char *username, const char *after,
+				  struct list_repos_res *res)
+{
+	int status = 0;
+	const struct gh_impl *c = client;
+	buffer_t buf = buffer_new(4096);
+
+	cJSON *args = cJSON_CreateObject();
+	if (!args) {
+		status = -1;
+		goto end;
+	}
+	cJSON_AddItemToObject(args, "username", cJSON_CreateString(username));
+	cJSON_AddItemToObject(args, "after", cJSON_CreateString(after));
+
+	const CURLcode ret = gh_impl_send(c, list_repos, args, &buf);
+	if (ret != CURLE_OK) {
+		fprintf(stderr, "Failed to send request: %s\n",
+			curl_easy_strerror(ret));
+		status = -1;
+		goto end;
+	}
+
+	// Parse the response
+	cJSON *root = cJSON_Parse((const char *) buf.data);
+	if (!root) {
+		const char *err = cJSON_GetErrorPtr();
+		if (err)
+			fprintf(stderr, "Error parsing response: %s\n", err);
+		status = -1;
+		goto end;
+	}
+
+	// Check for errors
+	if (gh_handle_error(root) < 0) {
+		status = -1;
+		goto end;
+	}
+
+	// Convert json to struct
+	if (list_repos_from_json(root, res) < 0) {
+		fprintf(stderr, "Failed to parse response\n");
+		status = -1;
+	}
+
+end:
+	buffer_free(buf);
+	return status;
+}
+
+/**
+ * Wraps the query in a JSON object with a "query" key and an optional
+ * "variables" key
+ * @param query GraphQL query
+ * @param args GraphQL arguments
+ * @return JSON string
+ */
+static char *wrap_query(const char *query, cJSON *args)
+{
+	cJSON *root = NULL, *query_str = NULL;
+	char *str = NULL;
+
+	root = cJSON_CreateObject();
+	if (!root)
+		return NULL;
+
+	query_str = cJSON_CreateString(query);
+	if (!query_str)
+		goto end;
+
+	// Transfer ownership of the string to root
+	cJSON_AddItemToObject(root, "query", query_str);
+
+	// Add the args object if it exists
+	if (args)
+		cJSON_AddItemToObject(root, "variables", args);
+
+	str = cJSON_Print(root);
+end:
+	cJSON_Delete(root);
+	return str;
+}
+
+static size_t write_data(const void *ptr, const size_t size, size_t nmemb,
+			 void *stream)
+{
+	(void) size; // unused
+
+	buffer_t *buf = stream;
+	buffer_append(buf, ptr, nmemb);
+	return nmemb;
+}
+
+/**
+ * Send a GraphQL query to the GitHub API
+ * @param client Github Client
+ * @param query GraphQL query
+ * @return CURLcode
+ */
+static CURLcode gh_impl_send(const struct gh_impl *client, const char *query,
+			     cJSON *args, buffer_t *buf)
+{
+	struct curl_slist *headers = NULL;
+	char auth[1024];
+
+	// Set the URL
+	curl_easy_setopt(client->curl, CURLOPT_URL, client->ctx.endpoint);
+
+	// Set the authorization header
+	snprintf(auth, sizeof(auth), "Authorization: bearer %s",
+		 client->ctx.token);
+	headers = curl_slist_append(headers, auth);
+	// Set the content type to JSON
+	headers = curl_slist_append(headers, "Content-Type: application/json");
+	curl_easy_setopt(client->curl, CURLOPT_HTTPHEADER, headers);
+
+	// Set user agent
+	curl_easy_setopt(client->curl, CURLOPT_USERAGENT,
+			 client->ctx.user_agent);
+
+	// Set the request type to POST
+	curl_easy_setopt(client->curl, CURLOPT_CUSTOMREQUEST, "POST");
+
+	// Prepare request body
+	char *wrapped_query = wrap_query(query, args);
+
+	// Set the request body
+	curl_easy_setopt(client->curl, CURLOPT_POSTFIELDS, wrapped_query);
+	curl_easy_setopt(client->curl, CURLOPT_POSTFIELDSIZE,
+			 strlen(wrapped_query));
+
+	// Set the write function to capture the response
+	curl_easy_setopt(client->curl, CURLOPT_WRITEFUNCTION, write_data);
+	curl_easy_setopt(client->curl, CURLOPT_WRITEDATA, (void *) buf);
+
+	// Perform the request
+	const CURLcode ret = curl_easy_perform(client->curl);
+
+	// Append null terminator to the buffer
+	if (ret == CURLE_OK)
+		buffer_append(buf, "\0", 1);
+
+	// Cleanup
+	free(wrapped_query);
+	curl_slist_free_all(headers);
+
+	return ret;
+}
+
+/**
+ * Handle errors in the response.
+ * Will check for the "errors" key in the response and print the error messages.
+ * Returns failure if any errors are found.
+ * @param root Parsed JSON response
+ * @return 0 on success (no errors), -1 on failure
+ */
+static int gh_handle_error(const cJSON *root)
+{
+	// Check for errors
+	cJSON *errors = cJSON_GetObjectItemCaseSensitive(root, "errors");
+	if (!errors || !cJSON_IsArray(errors)) {
+		// No errors
+		return 0;
+	}
+
+	cJSON *err;
+	cJSON_ArrayForEach(err, errors)
+	{
+		// Get the error message
+		cJSON *message = cJSON_GetObjectItemCaseSensitive(err,
+								  "message");
+		if (message && cJSON_IsString(message)) {
+			fprintf(stderr, "Github Error: %s\n",
+				message->valuestring);
+		} else {
+			fprintf(stderr, "Github Error: Unknown error\n");
+		}
+	}
+
+	return -1;
+}