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#ifndef SQLITE3_CSV_VTAB_ZSV_H
#define SQLITE3_CSV_VTAB_ZSV_H
#include <zsv.h>
#include <zsv/utils/prop.h>
/**
* when sqlite3 opens a CSV file using ZSV, it needs a way to know
* what options to open with (such as user-specified delimiter, header offset
* or span, etc
*
* In particular, it needs access to:
* - zsv options (struct zsv_opts)
* - custom property handler (struct zsv_prop_handler *)
* - options used (const char *) [but this can be passed via connection string]
*
* Some ways to pass this info are:
* - Embed it in the text of the URI passed to the module's xConnect function.
* This is not practical because we need to pass pointers
* - Use a single global variable that can hold only one set of data at a time.
* This was the old approach, via `zsv_set_default_opts` etc, which has the
* usual drawbacks of using a single global variable structure
* - Use a shared memory structure that can support multiple sets of data
* That is the approach implemented here. Data is identified by the related
* filename and caller pid
*
* sqlite3_create_module_v2 is passed the shared memory root pointer,
* but it's not really needed because there is no way for it to be
* dynamic so it always has to point to the single global location
*
* Prior to calling xConnect, the caller should save data for the related
* file via `sqlite3_zsv_data_add()`; xConnect then does a lookup to
* locate and use the saved data
*/
struct sqlite3_zsv_data;
void sqlite3_zsv_list_delete(struct sqlite3_zsv_data **list);
int sqlite3_zsv_list_add(const char *filename, struct zsv_opts *opts, struct zsv_prop_handler *custom_prop_handler);
struct sqlite3_zsv_data *sqlite3_csv_vtab_zsv_find(const char *filename);
/**
* Remove from list. Return 0 on success, non-zero on error
*/
int sqlite3_zsv_list_remove(const char *filename);
#endif
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