#include "database.js.h"

#include "log.h"
#include "mem.h"
#include "ssb.h"
#include "task.h"
#include "util.js.h"

#include "sqlite3.h"

#include <stdbool.h>
#include <string.h>

static JSClassID _database_class_id;
static int _database_count;

typedef struct _database_t
{
	JSContext* context;
	JSValue object;
	void* task;
	const char* id;
} database_t;

static JSValue _database_create(JSContext* context, JSValueConst this_val, int argc, JSValueConst* argv, int magic, JSValue* data);
static void _database_finalizer(JSRuntime* runtime, JSValue value);

static JSValue _database_get(JSContext* context, JSValueConst this_val, int argc, JSValueConst* argv);
static JSValue _database_set(JSContext* context, JSValueConst this_val, int argc, JSValueConst* argv);
static JSValue _database_exchange(JSContext* context, JSValueConst this_val, int argc, JSValueConst* argv);
static JSValue _database_remove(JSContext* context, JSValueConst this_val, int argc, JSValueConst* argv);
static JSValue _database_get_all(JSContext* context, JSValueConst this_val, int argc, JSValueConst* argv);
static JSValue _database_get_like(JSContext* context, JSValueConst this_val, int argc, JSValueConst* argv);
static JSValue _databases_list(JSContext* context, JSValueConst this_val, int argc, JSValueConst* argv, int magic, JSValue* data);

void tf_database_register(JSContext* context)
{
	JS_NewClassID(&_database_class_id);
	JSClassDef def = {
		.class_name = "Database",
		.finalizer = &_database_finalizer,
	};
	if (JS_NewClass(JS_GetRuntime(context), _database_class_id, &def) != 0)
	{
		tf_printf("Failed to register database.\n");
	}

	JSValue global = JS_GetGlobalObject(context);
	JSValue constructor = JS_NewCFunctionData(context, _database_create, 0, 0, 0, NULL);
	JS_SetConstructorBit(context, constructor, true);
	JS_SetPropertyStr(context, global, "Database", constructor);
	JSValue databases = JS_NewObject(context);
	JS_SetPropertyStr(context, global, "databases", databases);
	JS_SetPropertyStr(context, databases, "list", JS_NewCFunctionData(context, _databases_list, 0, 0, 0, NULL));
	JS_FreeValue(context, global);
}

static JSValue _database_create(JSContext* context, JSValueConst this_val, int argc, JSValueConst* argv, int magic, JSValue* data)
{
	++_database_count;
	JSValue object = JS_NewObjectClass(context, _database_class_id);

	database_t* database = tf_malloc(sizeof(database_t));
	*database = (database_t) {
		.task = JS_GetContextOpaque(context),
		.context = context,
		.object = object,
	};
	const char* id = JS_ToCString(context, argv[0]);
	database->id = tf_strdup(id);
	JS_FreeCString(context, id);
	JS_SetOpaque(object, database);

	JS_SetPropertyStr(context, object, "get", JS_NewCFunction(context, _database_get, "get", 1));
	JS_SetPropertyStr(context, object, "set", JS_NewCFunction(context, _database_set, "set", 2));
	JS_SetPropertyStr(context, object, "exchange", JS_NewCFunction(context, _database_exchange, "exchange", 2));
	JS_SetPropertyStr(context, object, "remove", JS_NewCFunction(context, _database_remove, "remove", 1));
	JS_SetPropertyStr(context, object, "getAll", JS_NewCFunction(context, _database_get_all, "getAll", 0));
	JS_SetPropertyStr(context, object, "getLike", JS_NewCFunction(context, _database_get_like, "getLike", 1));

	return object;
}

static void _database_finalizer(JSRuntime* runtime, JSValue value)
{
	database_t* database = JS_GetOpaque(value, _database_class_id);
	if (database)
	{
		tf_free((void*)database->id);
		tf_free(database);
	}
	--_database_count;
}

typedef struct _database_get_t
{
	const char* id;
	const char* key;
	size_t key_length;
	char* out_value;
	size_t out_length;
	JSValue promise[2];
} database_get_t;

static void _database_get_work(tf_ssb_t* ssb, void* user_data)
{
	database_get_t* work = user_data;
	sqlite3_stmt* statement;
	sqlite3* db = tf_ssb_acquire_db_reader(ssb);
	if (sqlite3_prepare(db, "SELECT value FROM properties WHERE id = ? AND key = ?", -1, &statement, NULL) == SQLITE_OK)
	{
		if (sqlite3_bind_text(statement, 1, work->id, -1, NULL) == SQLITE_OK && sqlite3_bind_text(statement, 2, work->key, work->key_length, NULL) == SQLITE_OK &&
			sqlite3_step(statement) == SQLITE_ROW)
		{
			size_t length = sqlite3_column_bytes(statement, 0);
			char* data = tf_malloc(length + 1);
			memcpy(data, sqlite3_column_text(statement, 0), length);
			data[length] = '\0';
			work->out_value = data;
			work->out_length = length;
		}
		sqlite3_finalize(statement);
	}
	tf_ssb_release_db_reader(ssb, db);
}

static void _database_get_after_work(tf_ssb_t* ssb, int status, void* user_data)
{
	database_get_t* work = user_data;
	JSContext* context = tf_ssb_get_context(ssb);
	JSValue result = JS_UNDEFINED;
	if (work->out_value)
	{
		result = JS_NewStringLen(context, work->out_value, work->out_length);
	}
	JSValue error = JS_Call(context, work->promise[0], JS_UNDEFINED, 1, &result);
	tf_util_report_error(context, error);
	JS_FreeValue(context, error);
	JS_FreeValue(context, result);
	JS_FreeValue(context, work->promise[0]);
	JS_FreeValue(context, work->promise[1]);
	tf_free(work->out_value);
	tf_free(work);
}

static JSValue _database_get(JSContext* context, JSValueConst this_val, int argc, JSValueConst* argv)
{
	JSValue result = JS_UNDEFINED;
	database_t* database = JS_GetOpaque(this_val, _database_class_id);
	if (database)
	{
		tf_ssb_t* ssb = tf_task_get_ssb(database->task);

		size_t length;
		const char* key = JS_ToCStringLen(context, &length, argv[0]);
		database_get_t* work = tf_malloc(sizeof(database_get_t) + strlen(database->id) + 1 + length + 1);
		*work = (database_get_t) {
			.id = (const char*)(work + 1),
			.key = (const char*)(work + 1) + strlen(database->id) + 1,
			.key_length = length,
		};
		memcpy((char*)work->id, database->id, strlen(database->id) + 1);
		memcpy((char*)work->key, key, length + 1);
		JS_FreeCString(context, key);

		tf_ssb_run_work(ssb, _database_get_work, _database_get_after_work, work);
		result = JS_NewPromiseCapability(context, work->promise);
	}
	return result;
}

typedef struct _database_set_t
{
	const char* id;
	const char* key;
	size_t key_length;
	const char* value;
	size_t value_length;
	bool result;
	JSValue promise[2];
} database_set_t;

static void _database_set_work(tf_ssb_t* ssb, void* user_data)
{
	database_set_t* work = user_data;
	sqlite3* db = tf_ssb_acquire_db_writer(ssb);
	sqlite3_stmt* statement;
	if (sqlite3_prepare(db, "INSERT OR REPLACE INTO properties (id, key, value) VALUES (?1, ?2, ?3)", -1, &statement, NULL) == SQLITE_OK)
	{
		if (sqlite3_bind_text(statement, 1, work->id, -1, NULL) == SQLITE_OK && sqlite3_bind_text(statement, 2, work->key, work->key_length, NULL) == SQLITE_OK &&
			sqlite3_bind_text(statement, 3, work->value, work->value_length, NULL) == SQLITE_OK && sqlite3_step(statement) == SQLITE_OK)
		{
			work->result = true;
		}
		sqlite3_finalize(statement);
	}
	tf_ssb_release_db_writer(ssb, db);
}

static void _database_set_after_work(tf_ssb_t* ssb, int status, void* user_data)
{
	database_set_t* work = user_data;
	JSContext* context = tf_ssb_get_context(ssb);
	JSValue result = work->result ? JS_TRUE : JS_UNDEFINED;
	JSValue error = JS_Call(context, work->promise[0], JS_UNDEFINED, 1, &result);
	tf_util_report_error(context, error);
	JS_FreeValue(context, error);
	JS_FreeValue(context, result);
	JS_FreeValue(context, work->promise[0]);
	JS_FreeValue(context, work->promise[1]);
	tf_free(work);
}

static JSValue _database_set(JSContext* context, JSValueConst this_val, int argc, JSValueConst* argv)
{
	JSValue result = JS_UNDEFINED;
	database_t* database = JS_GetOpaque(this_val, _database_class_id);
	if (database)
	{
		tf_ssb_t* ssb = tf_task_get_ssb(database->task);

		size_t key_length = 0;
		const char* key = JS_ToCStringLen(context, &key_length, argv[0]);
		size_t value_length = 0;
		const char* value = JS_ToCStringLen(context, &value_length, argv[1]);

		database_set_t* work = tf_malloc(sizeof(database_set_t) + strlen(database->id) + 1 + key_length + 1 + value_length + 1);
		*work = (database_set_t) {
			.id = (const char*)(work + 1),
			.key = (const char*)(work + 1) + strlen(database->id) + 1,
			.value = (const char*)(work + 1) + strlen(database->id) + 1 + key_length + 1,
			.key_length = key_length,
			.value_length = value_length,
		};

		memcpy((char*)work->id, database->id, strlen(database->id) + 1);
		memcpy((char*)work->key, key, key_length + 1);
		memcpy((char*)work->value, value, value_length + 1);

		result = JS_NewPromiseCapability(context, work->promise);
		tf_ssb_run_work(ssb, _database_set_work, _database_set_after_work, work);
		JS_FreeCString(context, key);
		JS_FreeCString(context, value);
	}
	return result;
}

static JSValue _database_exchange(JSContext* context, JSValueConst this_val, int argc, JSValueConst* argv)
{
	JSValue exchanged = JS_UNDEFINED;
	database_t* database = JS_GetOpaque(this_val, _database_class_id);
	if (database)
	{
		sqlite3_stmt* statement;
		tf_ssb_t* ssb = tf_task_get_ssb(database->task);
		sqlite3* db = tf_ssb_acquire_db_writer(ssb);
		if (JS_IsNull(argv[1]) || JS_IsUndefined(argv[1]))
		{
			if (sqlite3_prepare(db, "INSERT INTO properties (id, key, value) VALUES (?1, ?2, ?3) ON CONFLICT DO NOTHING", -1, &statement, NULL) == SQLITE_OK)
			{
				size_t key_length;
				size_t set_length;
				const char* key = JS_ToCStringLen(context, &key_length, argv[0]);
				const char* set = JS_ToCStringLen(context, &set_length, argv[2]);
				if (sqlite3_bind_text(statement, 1, database->id, -1, NULL) == SQLITE_OK && sqlite3_bind_text(statement, 2, key, key_length, NULL) == SQLITE_OK &&
					sqlite3_bind_text(statement, 3, set, set_length, NULL) == SQLITE_OK && sqlite3_step(statement) == SQLITE_DONE)
				{
					exchanged = sqlite3_changes(db) != 0 ? JS_TRUE : JS_FALSE;
				}
				JS_FreeCString(context, key);
				JS_FreeCString(context, set);
				sqlite3_finalize(statement);
			}
		}
		else if (sqlite3_prepare(db, "UPDATE properties SET value = ?1 WHERE id = ?2 AND key = ?3 AND value = ?4", -1, &statement, NULL) == SQLITE_OK)
		{
			size_t key_length;
			size_t expected_length;
			size_t set_length;
			const char* key = JS_ToCStringLen(context, &key_length, argv[0]);
			const char* expected = JS_ToCStringLen(context, &expected_length, argv[1]);
			const char* set = JS_ToCStringLen(context, &set_length, argv[2]);
			if (sqlite3_bind_text(statement, 1, set, set_length, NULL) == SQLITE_OK && sqlite3_bind_text(statement, 2, database->id, -1, NULL) == SQLITE_OK &&
				sqlite3_bind_text(statement, 3, key, key_length, NULL) == SQLITE_OK && sqlite3_bind_text(statement, 4, expected, expected_length, NULL) == SQLITE_OK &&
				sqlite3_step(statement) == SQLITE_DONE)
			{
				exchanged = sqlite3_changes(db) != 0 ? JS_TRUE : JS_FALSE;
			}
			JS_FreeCString(context, key);
			JS_FreeCString(context, expected);
			JS_FreeCString(context, set);
			sqlite3_finalize(statement);
		}
		tf_ssb_release_db_writer(ssb, db);
	}
	return exchanged;
}

static JSValue _database_remove(JSContext* context, JSValueConst this_val, int argc, JSValueConst* argv)
{
	database_t* database = JS_GetOpaque(this_val, _database_class_id);
	if (database)
	{
		sqlite3_stmt* statement;
		tf_ssb_t* ssb = tf_task_get_ssb(database->task);
		sqlite3* db = tf_ssb_acquire_db_writer(ssb);
		if (sqlite3_prepare(db, "DELETE FROM properties WHERE id = ?1 AND key = ?2", -1, &statement, NULL) == SQLITE_OK)
		{
			size_t keyLength;
			const char* keyString = JS_ToCStringLen(context, &keyLength, argv[0]);
			if (sqlite3_bind_text(statement, 1, database->id, -1, NULL) == SQLITE_OK && sqlite3_bind_text(statement, 2, keyString, keyLength, NULL) == SQLITE_OK &&
				sqlite3_step(statement) == SQLITE_OK)
			{
			}
			JS_FreeCString(context, keyString);
			sqlite3_finalize(statement);
		}
		tf_ssb_release_db_writer(ssb, db);
	}
	return JS_UNDEFINED;
}

static JSValue _database_get_all(JSContext* context, JSValueConst this_val, int argc, JSValueConst* argv)
{
	JSValue array = JS_UNDEFINED;
	database_t* database = JS_GetOpaque(this_val, _database_class_id);
	if (database)
	{
		sqlite3_stmt* statement;
		tf_ssb_t* ssb = tf_task_get_ssb(database->task);
		sqlite3* db = tf_ssb_acquire_db_reader(ssb);
		if (sqlite3_prepare(db, "SELECT key, value FROM properties WHERE id = ?1", -1, &statement, NULL) == SQLITE_OK)
		{
			if (sqlite3_bind_text(statement, 1, database->id, -1, NULL) == SQLITE_OK)
			{
				array = JS_NewArray(context);
				uint32_t index = 0;
				while (sqlite3_step(statement) == SQLITE_ROW)
				{
					JS_SetPropertyUint32(context, array, index++, JS_NewStringLen(context, (const char*)sqlite3_column_text(statement, 0), sqlite3_column_bytes(statement, 0)));
				}
			}
			sqlite3_finalize(statement);
		}
		tf_ssb_release_db_reader(ssb, db);
	}
	return array;
}

static JSValue _database_get_like(JSContext* context, JSValueConst this_val, int argc, JSValueConst* argv)
{
	JSValue result = JS_UNDEFINED;
	database_t* database = JS_GetOpaque(this_val, _database_class_id);
	if (database)
	{
		sqlite3_stmt* statement;
		tf_ssb_t* ssb = tf_task_get_ssb(database->task);
		sqlite3* db = tf_ssb_acquire_db_reader(ssb);
		if (sqlite3_prepare(db, "SELECT key, value FROM properties WHERE id = ? AND KEY LIKE ?", -1, &statement, NULL) == SQLITE_OK)
		{
			const char* pattern = JS_ToCString(context, argv[0]);
			if (sqlite3_bind_text(statement, 1, database->id, -1, NULL) == SQLITE_OK && sqlite3_bind_text(statement, 2, pattern, -1, NULL) == SQLITE_OK)
			{
				result = JS_NewObject(context);
				while (sqlite3_step(statement) == SQLITE_ROW)
				{
					JS_SetPropertyStr(context, result, (const char*)sqlite3_column_text(statement, 0),
						JS_NewStringLen(context, (const char*)sqlite3_column_text(statement, 1), sqlite3_column_bytes(statement, 1)));
				}
			}
			JS_FreeCString(context, pattern);
			sqlite3_finalize(statement);
		}
		tf_ssb_release_db_reader(ssb, db);
	}
	return result;
}

static JSValue _databases_list(JSContext* context, JSValueConst this_val, int argc, JSValueConst* argv, int magic, JSValue* data)
{
	tf_task_t* task = tf_task_get(context);
	tf_ssb_t* ssb = tf_task_get_ssb(task);
	sqlite3* db = tf_ssb_acquire_db_reader(ssb);
	JSValue array = JS_UNDEFINED;
	sqlite3_stmt* statement;
	if (sqlite3_prepare(db, "SELECT DISTINCT id FROM properties WHERE id LIKE ?", -1, &statement, NULL) == SQLITE_OK)
	{
		const char* pattern = JS_ToCString(context, argv[0]);
		if (sqlite3_bind_text(statement, 1, pattern, -1, NULL) == SQLITE_OK)
		{
			array = JS_NewArray(context);
			uint32_t index = 0;
			while (sqlite3_step(statement) == SQLITE_ROW)
			{
				JS_SetPropertyUint32(context, array, index++, JS_NewStringLen(context, (const char*)sqlite3_column_text(statement, 0), sqlite3_column_bytes(statement, 0)));
			}
		}
		JS_FreeCString(context, pattern);
		sqlite3_finalize(statement);
	}
	tf_ssb_release_db_reader(ssb, db);
	return array;
}