#include <stdio.h>

#include <spdk/event.h>
#include <spdk/blob.h>
#include <spdk/bdev.h>
#include <spdk/blob_bdev.h>
#include <spdk/env.h>



#define BUFFER_SIZE		512


#define FILENAME_LENGTH  128

typedef struct zvfs_s {

	struct spdk_blob_store *blobstore;
	uint64_t unit_size;
	uint64_t free_cluster_count;
	uint64_t num_cluster;

	struct spdk_io_channel *channel;

	bool finished;
} zvfs_t;

typedef struct zvfs_operation_s {
	int (*mount)(struct zvfs_s *fs);
	int (*umount)(struct zvfs_s *fs);
} zvfs_operation_t;

typedef struct zvfs_file_s {

	uint8_t filename[FILENAME_LENGTH];

	spdk_blob_id blob_id;
	struct spdk_blob *blob;
	zvfs_t *fs;

	uint8_t *write_buffer;
	uint8_t *read_buffer;

	bool finished;
	
} zvfs_file_t;

typedef struct zvfs_file_operation_s {

	int (*open)(struct zvfs_file_s *file);
	int (*read)(struct zvfs_file_s *file);
	int (*write)(struct zvfs_file_s *file);
	int (*close)(struct zvfs_file_s *file);
	
} zvfs_file_operation_t;



struct spdk_thread *global_thread = NULL;
static const int WAITER_MAX_TIME = 100000;

// mount
void zvfs_do_mount(void *arg);
void zvfs_spdk_bdev_event_cb(enum spdk_bdev_event_type type, struct spdk_bdev *bdev, void *event_ctx);
void zvfs_spdk_bs_init_cb(void *arg, struct spdk_blob_store *bs, int bserrno);

// open
void zvfs_do_create(void *arg);
void zvfs_spdk_bs_create_blob_cb(void *arg, spdk_blob_id blobid, int bserrno);
void zvfs_spdk_bs_open_blob_create_cb(void *arg, struct spdk_blob *blb, int bserrno);
void zvfs_spdk_blob_resize_cb(void *arg, int bserrno);
void zvfs_spdk_blob_sync_cb(void *arg, int bserrno);

// read
void zvfs_do_read(void *arg);
void zvfs_spdk_blob_read_cb(void *arg, int bserrno);

// write
void zvfs_do_write(void *arg);
void zvfs_spdk_blob_write_cb(void *arg, int bserrno);


// close
void zvfs_do_close(void *arg);
void zvfs_spdk_blob_close_cb(void *arg, int bserrno);
void zvfs_spdk_blob_delete_cb(void *arg, int bserrno);

// waiter 
bool waiter(struct spdk_thread *thread, spdk_msg_fn start_fn, void *ctx, bool *finished);

// setup
int zvfs_env_setup(void);
void zvfs_json_load_fn(void *arg);
void json_app_load_done(int rc, void *ctx);

// unmount
void zvfs_do_umount(void *arg);
void zvfs_spdk_bs_unload_cb(void *arg, int bserrno);

// mount
void zvfs_do_mount(void *arg) {

	zvfs_t *fs = (zvfs_t*)arg;
	
	struct spdk_bs_dev *bs_dev = NULL;

	int rc = spdk_bdev_create_bs_dev_ext("Malloc0", zvfs_spdk_bdev_event_cb, NULL, &bs_dev);
	if (rc != 0) {
		spdk_app_stop(0);
	}

	spdk_bs_init(bs_dev, NULL, zvfs_spdk_bs_init_cb, fs);

	SPDK_NOTICELOG("zvfs_entry\n");

}

void zvfs_spdk_bdev_event_cb(enum spdk_bdev_event_type type, struct spdk_bdev *bdev,
				     void *event_ctx) {
	SPDK_NOTICELOG("zvfs_spdk_bdev_event_cb\n");
}

void zvfs_spdk_bs_init_cb(void *arg, struct spdk_blob_store *bs, int bserrno) {
	zvfs_t *fs = (zvfs_t*)arg;

	uint64_t io_unit_size = spdk_bs_get_io_unit_size(bs);
	SPDK_NOTICELOG("io_unit_size : %"PRIu64"\n", io_unit_size);

	fs->unit_size = io_unit_size;
	fs->blobstore = bs;

	fs->channel = spdk_bs_alloc_io_channel(fs->blobstore);
	if (fs->channel == NULL) {
		return ;
	}

	fs->finished = true;

	SPDK_NOTICELOG("mount finished\n");
}


// open
void zvfs_do_create(void *arg) {
	zvfs_file_t *file = (zvfs_file_t *)arg;
	
	spdk_bs_create_blob(file->fs->blobstore, zvfs_spdk_bs_create_blob_cb, file);

}

void zvfs_spdk_bs_create_blob_cb(void *arg, spdk_blob_id blobid, int bserrno) {
	zvfs_file_t *file = (zvfs_file_t *)arg;

	file->blob_id = blobid;
	SPDK_NOTICELOG("blobid : %"PRIu64"\n", blobid);

	spdk_bs_open_blob(file->fs->blobstore, blobid, zvfs_spdk_bs_open_blob_create_cb, file);
}

void zvfs_spdk_bs_open_blob_create_cb(void *arg, struct spdk_blob *blb, int bserrno) {
	zvfs_file_t *file = (zvfs_file_t *)arg;

	file->blob = blb;

	uint64_t free_cluster = spdk_bs_free_cluster_count(file->fs->blobstore);  //
	SPDK_NOTICELOG("free_cluster : %"PRIu64"\n", free_cluster);
	file->fs->free_cluster_count = free_cluster;

	spdk_blob_resize(blb, free_cluster, zvfs_spdk_blob_resize_cb, file);

}

void zvfs_spdk_blob_resize_cb(void *arg, int bserrno) {
	zvfs_file_t *file = (zvfs_file_t *)arg;
	
	uint64_t total = spdk_blob_get_num_clusters(file->blob);
	file->fs->num_cluster = total;

	SPDK_NOTICELOG("resize blob :%"PRIu64"\n", total);

	spdk_blob_sync_md(file->blob, zvfs_spdk_blob_sync_cb, file);

}

void zvfs_spdk_blob_sync_cb(void *arg, int bserrno) {
	zvfs_file_t *file = (zvfs_file_t *)arg;
	file->write_buffer = spdk_malloc(BUFFER_SIZE, 0x1000, NULL, SPDK_ENV_LCORE_ID_ANY, SPDK_MALLOC_DMA);
	if (file->write_buffer == NULL) {
		return ;
	}

	file->read_buffer = spdk_malloc(BUFFER_SIZE, 0x1000, NULL, SPDK_ENV_LCORE_ID_ANY, SPDK_MALLOC_DMA);
	if (file->read_buffer == NULL) {
		return ;
	}
	

	SPDK_NOTICELOG("open complete\n");

	file->finished = true;
}

// read
void zvfs_do_read(void *arg) {
	zvfs_file_t *file = (zvfs_file_t *)arg;
	memset(file->read_buffer, 0x0, BUFFER_SIZE);
	spdk_blob_io_read(file->blob, file->fs->channel, file->read_buffer, 
		0, 1, zvfs_spdk_blob_read_cb, file);
}

void zvfs_spdk_blob_read_cb(void *arg, int bserrno) {

	zvfs_file_t *file = (zvfs_file_t *)arg;

	SPDK_NOTICELOG("READ BUFFER : %s\n", file->read_buffer);

	file->finished = true;
}


// write
void zvfs_do_write(void *arg) {
	zvfs_file_t *file = (zvfs_file_t *)arg;
	spdk_blob_io_write(file->blob, file->fs->channel, file->write_buffer, 
		0, 1, zvfs_spdk_blob_write_cb, file);
}

void zvfs_spdk_blob_write_cb(void *arg, int bserrno) {
	zvfs_file_t *file = (zvfs_file_t *)arg;
	SPDK_NOTICELOG("write complete\n");

	file->finished = true;
}

// close 
void zvfs_do_close(void *arg) {
	zvfs_file_t *file = (zvfs_file_t *)arg;
	spdk_blob_close(file->blob, zvfs_spdk_blob_close_cb, file);
}

void zvfs_spdk_blob_close_cb(void *arg, int bserrno) {
	zvfs_file_t *file = (zvfs_file_t *)arg;
	spdk_bs_delete_blob(file->fs->blobstore, file->blob_id, zvfs_spdk_blob_delete_cb, file);
}

void zvfs_spdk_blob_delete_cb(void *arg, int bserrno) {
	zvfs_file_t *file = (zvfs_file_t *)arg;
	
	spdk_free(file->write_buffer);
	spdk_free(file->read_buffer);

	SPDK_NOTICELOG("close complete\n");
	file->finished = true;
}

// unmount
void zvfs_do_umount(void *arg) {

	zvfs_t *fs = (zvfs_t *)arg;

	if (fs->blobstore) {
		if (fs->channel) {
			spdk_bs_free_io_channel(fs->channel);
		}
		spdk_bs_unload(fs->blobstore, zvfs_spdk_bs_unload_cb, fs);
	}
	
}

void zvfs_spdk_bs_unload_cb(void *arg, int bserrno) {

	zvfs_t *fs = (zvfs_t *)arg;
	fs->finished = true;
}

// waiter 
bool waiter(struct spdk_thread *thread, spdk_msg_fn start_fn, void *ctx, bool *finished) {

	spdk_thread_send_msg(thread, start_fn, ctx);

	int waiter_count = 0;

	do {
		spdk_thread_poll(thread, 0, 0);
		waiter_count ++; 
	} while(!(*finished) && waiter_count < WAITER_MAX_TIME);

	if (!(*finished) && waiter_count >= WAITER_MAX_TIME) {
		return false; // timeout
	}

	return true;
}

// setup
// zvfs.json
static const char *json_file = "/home/lian/share/10.1-spdk/zvfs/zvfs.json";

int zvfs_env_setup(void) {
	struct spdk_env_opts opts;
	spdk_env_opts_init(&opts);

	if (0 != spdk_env_init(&opts)) {
		return -1;
	}

	spdk_log_set_print_level(SPDK_LOG_NOTICE);
	spdk_log_set_level(SPDK_LOG_NOTICE);
	spdk_log_open(NULL);

	spdk_thread_lib_init(NULL, 0);
	global_thread = spdk_thread_create("global", NULL);
	spdk_set_thread(global_thread);

	bool done = false;

	waiter(global_thread, zvfs_json_load_fn, &done, &done);
	SPDK_NOTICELOG("json_app_load_done complete\n");


	return 0;
	
}

void zvfs_json_load_fn(void *arg) {
	spdk_subsystem_init_from_json_config(json_file, SPDK_DEFAULT_RPC_ADDR, json_app_load_done,
		arg, true);
	
}

void json_app_load_done(int rc, void *ctx) {
	bool *done = ctx;
	*done = true;

	SPDK_NOTICELOG("json_app_load_done\n");
}


// filesystem
// load
static int zvfs_mount(struct zvfs_s *fs) {

	fs->finished = false;

	return waiter(global_thread, zvfs_do_mount, fs, &fs->finished);
} 


// unload
static int zvfs_umount(struct zvfs_s *fs) {

	fs->finished = false;
	
	return waiter(global_thread, zvfs_do_umount, fs, &fs->finished);
}


// file
// open
static int zvfs_create(struct zvfs_file_s *file) {

	file->finished = false;
	
	return waiter(global_thread, zvfs_do_create, file, &file->finished);
	
}


// read
static int zvfs_read(struct zvfs_file_s *file, uint8_t *buffer, size_t count) {

	file->finished = false;
	waiter(global_thread, zvfs_do_read, file, &file->finished);

	int len = strlen(file->read_buffer);
	memcpy(buffer, file->read_buffer, len);  //

	return len;
}


// write
static int zvfs_write(struct zvfs_file_s *file, const uint8_t *buffer, size_t count) {

	file->finished = false;

	memcpy(file->write_buffer, buffer, count);  // count / 512
	
	return waiter(global_thread, zvfs_do_write, file, &file->finished);
}

// close
static int zvfs_close(struct zvfs_file_s *file) {

	file->finished = false;

	return waiter(global_thread, zvfs_do_close, file, &file->finished);
}


int main(int argc, char *argv[]) {

	if (zvfs_env_setup()) {
		return -1;
	}

	SPDK_NOTICELOG("zvfs_env_setup success\n");

	SPDK_NOTICELOG("\n\n zvfs mount start \n\n");
	zvfs_t *fs = calloc(1, sizeof(zvfs_t));
	zvfs_mount(fs);

	SPDK_NOTICELOG("\n\n zvfs open start \n\n");
	zvfs_file_t *file = calloc(1, sizeof(zvfs_file_t));
	file->fs = fs;
	zvfs_create(file);


	SPDK_NOTICELOG("\n\n zvfs write start \n\n");
	char *buffer = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
	zvfs_write(file, buffer, strlen(buffer));


	SPDK_NOTICELOG("\n\n zvfs read start \n\n");
	char rbuffer[BUFFER_SIZE] = {0};
	zvfs_read(file, rbuffer, BUFFER_SIZE);
	SPDK_NOTICELOG("READ BUFFER: %s\n", rbuffer);

	SPDK_NOTICELOG("\n\n zvfs close start \n\n");
	zvfs_close(file);

	free(file);

	SPDK_NOTICELOG("\n\n zvfs umount start \n\n");
	zvfs_umount(fs);
	free(fs);
	
}