/*
 * Copyright (c) 2011, Google Inc.
 */
#ifndef CONVERT_H
#define CONVERT_H

#include "hash.h"
#include "string-list.h"

struct index_state;
struct strbuf;

#define CONV_EOL_RNDTRP_DIE   (1<<0) /* Die if CRLF to LF to CRLF is different */
#define CONV_EOL_RNDTRP_WARN  (1<<1) /* Warn if CRLF to LF to CRLF is different */
#define CONV_EOL_RENORMALIZE  (1<<2) /* Convert CRLF to LF */
#define CONV_EOL_KEEP_CRLF    (1<<3) /* Keep CRLF line endings as is */
#define CONV_WRITE_OBJECT     (1<<4) /* Content is written to the index */

extern int global_conv_flags_eol;

enum auto_crlf {
	AUTO_CRLF_FALSE = 0,
	AUTO_CRLF_TRUE = 1,
	AUTO_CRLF_INPUT = -1
};

extern enum auto_crlf auto_crlf;

enum eol {
	EOL_UNSET,
	EOL_CRLF,
	EOL_LF,
#ifdef NATIVE_CRLF
	EOL_NATIVE = EOL_CRLF
#else
	EOL_NATIVE = EOL_LF
#endif
};

enum ce_delay_state {
	CE_NO_DELAY = 0,
	CE_CAN_DELAY = 1,
	CE_RETRY = 2
};

struct delayed_checkout {
	/*
	 * State of the currently processed cache entry. If the state is
	 * CE_CAN_DELAY, then the filter can delay the current cache entry.
	 * If the state is CE_RETRY, then this signals the filter that the
	 * cache entry was requested before.
	 */
	enum ce_delay_state state;
	/* List of filter drivers that signaled delayed blobs. */
	struct string_list filters;
	/*
	 * List of delayed blobs identified by their path. The `util` member
	 * holds a counter pointer which must be incremented when/if the
	 * associated blob gets checked out.
	 */
	struct string_list paths;
};

struct checkout_metadata {
	const char *refname;
	struct object_id treeish;
	struct object_id blob;
};

enum convert_crlf_action {
	CRLF_UNDEFINED,
	CRLF_BINARY,
	CRLF_TEXT,
	CRLF_TEXT_INPUT,
	CRLF_TEXT_CRLF,
	CRLF_AUTO,
	CRLF_AUTO_INPUT,
	CRLF_AUTO_CRLF
};

struct convert_driver;

struct conv_attrs {
	struct convert_driver *drv;
	enum convert_crlf_action attr_action; /* What attr says */
	enum convert_crlf_action crlf_action; /* When no attr is set, use core.autocrlf */
	int ident;
	const char *working_tree_encoding; /* Supported encoding or default encoding if NULL */
};

void convert_attrs(struct index_state *istate,
		   struct conv_attrs *ca, const char *path);

extern enum eol core_eol;
extern char *check_roundtrip_encoding;
const char *get_cached_convert_stats_ascii(struct index_state *istate,
					   const char *path);
const char *get_wt_convert_stats_ascii(const char *path);
const char *get_convert_attr_ascii(struct index_state *istate,
				   const char *path);

/* returns 1 if *dst was used */
int convert_to_git(struct index_state *istate,
		   const char *path, const char *src, size_t len,
		   struct strbuf *dst, int conv_flags);
int convert_to_working_tree_ca(const struct conv_attrs *ca,
			       const char *path, const char *src,
			       size_t len, struct strbuf *dst,
			       const struct checkout_metadata *meta);
int async_convert_to_working_tree_ca(const struct conv_attrs *ca,
				     const char *path, const char *src,
				     size_t len, struct strbuf *dst,
				     const struct checkout_metadata *meta,
				     void *dco);
static inline int convert_to_working_tree(struct index_state *istate,
					  const char *path, const char *src,
					  size_t len, struct strbuf *dst,
					  const struct checkout_metadata *meta)
{
	struct conv_attrs ca;
	convert_attrs(istate, &ca, path);
	return convert_to_working_tree_ca(&ca, path, src, len, dst, meta);
}
static inline int async_convert_to_working_tree(struct index_state *istate,
						const char *path, const char *src,
						size_t len, struct strbuf *dst,
						const struct checkout_metadata *meta,
						void *dco)
{
	struct conv_attrs ca;
	convert_attrs(istate, &ca, path);
	return async_convert_to_working_tree_ca(&ca, path, src, len, dst, meta, dco);
}
int async_query_available_blobs(const char *cmd,
				struct string_list *available_paths);
int renormalize_buffer(struct index_state *istate,
		       const char *path, const char *src, size_t len,
		       struct strbuf *dst);
static inline int would_convert_to_git(struct index_state *istate,
				       const char *path)
{
	return convert_to_git(istate, path, NULL, 0, NULL, 0);
}
/* Precondition: would_convert_to_git_filter_fd(path) == true */
void convert_to_git_filter_fd(struct index_state *istate,
			      const char *path, int fd,
			      struct strbuf *dst,
			      int conv_flags);
int would_convert_to_git_filter_fd(struct index_state *istate,
				   const char *path);

/*
 * Initialize the checkout metadata with the given values.  Any argument may be
 * NULL if it is not applicable.  The treeish should be a commit if that is
 * available, and a tree otherwise.
 *
 * The refname is not copied and must be valid for the lifetime of the struct.
 * THe object IDs are copied.
 */
void init_checkout_metadata(struct checkout_metadata *meta, const char *refname,
			    const struct object_id *treeish,
			    const struct object_id *blob);

/* Copy the metadata from src to dst, updating the blob. */
void clone_checkout_metadata(struct checkout_metadata *dst,
			     const struct checkout_metadata *src,
			     const struct object_id *blob);

/*
 * Reset the internal list of attributes used by convert_to_git and
 * convert_to_working_tree.
 */
void reset_parsed_attributes(void);

/*****************************************************************
 *
 * Streaming conversion support
 *
 *****************************************************************/

struct stream_filter; /* opaque */

struct stream_filter *get_stream_filter(struct index_state *istate,
					const char *path,
					const struct object_id *);
struct stream_filter *get_stream_filter_ca(const struct conv_attrs *ca,
					   const struct object_id *oid);
void free_stream_filter(struct stream_filter *);
int is_null_stream_filter(struct stream_filter *);

/*
 * Use as much input up to *isize_p and fill output up to *osize_p;
 * update isize_p and osize_p to indicate how much buffer space was
 * consumed and filled. Return 0 on success, non-zero on error.
 *
 * Some filters may need to buffer the input and look-ahead inside it
 * to decide what to output, and they may consume more than zero bytes
 * of input and still not produce any output. After feeding all the
 * input, pass NULL as input and keep calling this function, to let
 * such filters know there is no more input coming and it is time for
 * them to produce the remaining output based on the buffered input.
 */
int stream_filter(struct stream_filter *,
		  const char *input, size_t *isize_p,
		  char *output, size_t *osize_p);

enum conv_attrs_classification {
	/*
	 * The blob must be loaded into a buffer before it can be
	 * smudged. All smudging is done in-proc.
	 */
	CA_CLASS_INCORE,

	/*
	 * The blob must be loaded into a buffer, but uses a
	 * single-file driver filter, such as rot13.
	 */
	CA_CLASS_INCORE_FILTER,

	/*
	 * The blob must be loaded into a buffer, but uses a
	 * long-running driver process, such as LFS. This might or
	 * might not use delayed operations. (The important thing is
	 * that there is a single subordinate long-running process
	 * handling all associated blobs and in case of delayed
	 * operations, may hold per-blob state.)
	 */
	CA_CLASS_INCORE_PROCESS,

	/*
	 * The blob can be streamed and smudged without needing to
	 * completely read it into a buffer.
	 */
	CA_CLASS_STREAMABLE,
};

enum conv_attrs_classification classify_conv_attrs(
	const struct conv_attrs *ca);

#endif /* CONVERT_H */