From 41dd937d41dd06a74965efdf1ef1423cefbb4617 Mon Sep 17 00:00:00 2001
From: teknomunk <teknomunk@protonmail.com>
Date: Sat, 24 Dec 2022 08:51:47 -0600
Subject: [PATCH] Add hash index

---
 hash_index.c | 149 +++++++++++++++++++++++++++++++++++++++++++++++++++
 hash_index.h |   7 +++
 2 files changed, 156 insertions(+)
 create mode 100644 hash_index.c
 create mode 100644 hash_index.h

diff --git a/hash_index.c b/hash_index.c
new file mode 100644
index 0000000..54211c8
--- /dev/null
+++ b/hash_index.c
@@ -0,0 +1,149 @@
+#include "hash_index.h"
+
+// Submodules
+#include "collections/array.h"
+#include "json/json.h"
+#include "json/layout.h"
+#include "sha256/sha256.h"
+
+// Stdlib
+#include <stdlib.h>
+
+struct hash_index_entry
+{
+	char* key;
+	int value;
+};
+
+extern struct json_field_type hash_index_entry_type;
+static struct json_object_field hash_index_entry_layout[] = {
+	{ "key",	offsetof( struct hash_index_entry, key ),	true,  &json_field_string },
+	{ "val",	offsetof( struct hash_index_entry, value ),	true,  &json_field_integer },
+	{ NULL,	0,									true,  NULL,  &hash_index_entry_type },
+};
+
+static void* alloc_hash_index_entry()
+{
+	void* ptr = malloc(sizeof(struct hash_index_entry));
+	memset( ptr, 0, sizeof(struct hash_index_entry));
+	return ptr;
+}
+static void free_hash_index_entry( void* ptr )
+{
+	struct hash_index_entry* rie = ptr;
+	free(rie->key);
+	free(rie);
+}
+
+static bool hie_reader( struct json_pull_parser* jpp, void* field_data, struct json_object_field* layout_field_data )
+{
+	void* data = *(void**)field_data = malloc(sizeof(struct hash_index_entry));
+	bool res = json_read_object_layout( jpp, hash_index_entry_layout, data );
+	if( !res ) {
+		free( data );
+	}
+	return res;
+}
+static bool hie_writer( struct json_writer* jw, const char* field_name, void* field_data, struct json_object_field* layout_field_data )
+{
+	json_write_field_name(jw,field_name);
+	json_write_pretty_object_layout( jw, hash_index_entry_layout, *(void**)field_data );
+	return true;
+}
+
+struct json_field_type hash_index_entry_type = {
+	.reader = hie_reader,
+	.writer = hie_writer,
+	.size = sizeof(void*),
+	.layout = hash_index_entry_layout,
+	.alloc = alloc_hash_index_entry,
+	.free = free_hash_index_entry,
+};
+
+struct hash_index
+{
+	struct {
+		struct hash_index_entry** items;
+		int count;
+	} entries;
+};
+
+	static struct json_object_field hash_index_layout[] = {
+		{ "entries",		offsetof( struct hash_index, entries ),	true,  &json_field_array_of, &hash_index_entry_type },
+		{ NULL },
+	};
+bool hash_index_set( const char* index, const char* key, int value )
+{
+	char hash[65] = "";
+	sha256_easy_hash_hex( key, strlen(key), hash );
+	hash[5] = '\0';
+
+	char filename[512];
+	snprintf( filename, 512, "%s/%s.json", index, hash );
+
+	struct hash_index hi;
+	memset( &hi, 0, sizeof(hi) );
+	json_read_object_layout_from_file( filename, hash_index_layout, &hi );
+
+	struct hash_index_entry new_entry = {
+		.key = (char*)key,
+		.value = value,
+	};
+	struct hash_index_entry* ptr = &new_entry;
+
+	/*
+	for( int i = 0; i < ari.entries.count; ++i ) {
+		struct reverse_index_entry* entry = ari.entries.items[i];
+		printf( "\tentry[%d] = { .uri = %s, .account_id = %d }\n", i, entry->uri, entry->account_id );
+	}
+	//*/
+
+	array_append( &hi.entries, sizeof(struct hash_index_entry), &ptr );
+
+	json_write_object_layout_to_file( filename, "\t", hash_index_layout, &hi );
+
+	for( int i = 0; i < hi.entries.count-1; ++i ) {
+		struct hash_index_entry* entry = hi.entries.items[i];
+		free(entry->key);
+		free(entry);
+	}
+}
+
+bool hash_index_get( const char* index, const char* key, int* value )
+{
+	char hash[65] = "";
+	sha256_easy_hash_hex( key, strlen(key), hash );
+	hash[5] = '\0';
+
+	char filename[512];
+	snprintf( filename, 512, "%s/%s.json", index, hash );
+
+	struct hash_index hi;
+	memset( &hi, 0, sizeof(hi) );
+	if( !json_read_object_layout_from_file( filename, hash_index_layout, &hi ) ) {
+		return -1;
+	}
+
+	/*
+	for( int i = 0; i < ari.entries.count; ++i ) {
+		struct reverse_index_entry* entry = ari.entries.items[i];
+		printf( "\tentry[%d] = %p{ .uri = %s, .account_id = %d }\n", i, entry, entry->uri, entry->account_id );
+	}
+	//*/
+
+	bool found = false;
+	*value = -1;
+	for( int i = 0; i < hi.entries.count; ++i ) {
+		struct hash_index_entry* entry = hi.entries.items[i];
+		if( 0 == strcmp(entry->key,key) ) {
+			*value = entry->value;
+			found = true;
+		}
+		free(entry->key);
+		free(entry);
+	}
+	free(hi.entries.items);
+
+	return found;
+}
+
diff --git a/hash_index.h b/hash_index.h
new file mode 100644
index 0000000..24f0ab0
--- /dev/null
+++ b/hash_index.h
@@ -0,0 +1,7 @@
+#pragma once
+
+#include <stdbool.h>
+
+bool hash_index_set( const char* index, const char* key, int value );
+bool hash_index_get( const char* index, const char* key, int* value );
+