/** \file highlight.h
  Prototypes for functions for syntax highlighting
*/

#ifndef FISH_HIGHLIGHT_H
#define FISH_HIGHLIGHT_H

#include <wchar.h>

#include "env.h"
#include "util.h"
#include "color.h"

/* Internally, we specify highlight colors using a set of bits. Each highlight_spec is a 32 bit uint. We divide this into low 16 (foreground) and high 16 (background). Each half we further subdivide into low 8 (primary) and high 8 (modifiers). The primary is not a bitmask; specify exactly one. The modifiers are a bitmask; specify any number */
enum
{
    /* The following values are mutually exclusive; specify at most one */
    highlight_spec_normal = 0, // normal text
    highlight_spec_error, // error
    highlight_spec_command, //command
    highlight_spec_statement_terminator, //process separator
    highlight_spec_param, //command parameter (argument)
    highlight_spec_comment, //comment
    highlight_spec_match, //matching parenthesis, etc.
    highlight_spec_search_match, //search match
    highlight_spec_operator, //operator
    highlight_spec_escape, //escape sequences
    highlight_spec_quote, //quoted string
    highlight_spec_redirection, //redirection
    highlight_spec_autosuggestion, //autosuggestion
    highlight_spec_selection,

    // Pager support
    highlight_spec_pager_prefix,
    highlight_spec_pager_completion,
    highlight_spec_pager_description,
    highlight_spec_pager_progress,
    highlight_spec_pager_secondary,

    HIGHLIGHT_SPEC_PRIMARY_MASK = 0xFF,

    /* The following values are modifiers */
    highlight_modifier_valid_path = 0x100,
    highlight_modifier_force_underline = 0x200,
    highlight_modifier_sloppy_background = 0x300, //hackish, indicates that we should treat a foreground color as background, per certain historical behavior

    /* Very special value */
    highlight_spec_invalid = 0xFFFF

};
typedef uint32_t highlight_spec_t;

inline highlight_spec_t highlight_get_primary(highlight_spec_t val)
{
    return val & HIGHLIGHT_SPEC_PRIMARY_MASK;
}

inline highlight_spec_t highlight_make_background(highlight_spec_t val)
{
    assert(val >> 16 == 0); //should have nothing in upper bits, otherwise this is already a background
    return val << 16;
}

class history_item_t;
struct file_detection_context_t;

/**
   Perform syntax highlighting for the shell commands in buff. The result is
   stored in the color array as a color_code from the HIGHLIGHT_ enum
   for each character in buff.

   \param buff The buffer on which to perform syntax highlighting
   \param color The array in wchich to store the color codes. The first 8 bits are used for fg color, the next 8 bits for bg color.
   \param pos the cursor position. Used for quote matching, etc.
   \param error a list in which a description of each error will be inserted. May be 0, in whcich case no error descriptions will be generated.
*/
void highlight_shell(const wcstring &buffstr, std::vector<highlight_spec_t> &color, size_t pos, wcstring_list_t *error, const env_vars_snapshot_t &vars);

/**
   Perform a non-blocking shell highlighting. The function will not do any I/O that may block. As a result, invalid commands may not be detected, etc.
*/
void highlight_shell_no_io(const wcstring &buffstr, std::vector<highlight_spec_t> &color, size_t pos, wcstring_list_t *error, const env_vars_snapshot_t &vars);

/**
   Perform syntax highlighting for the text in buff. Matching quotes and paranthesis are highlighted. The result is
   stored in the color array as a color_code from the HIGHLIGHT_ enum
   for each character in buff.

   \param buff The buffer on which to perform syntax highlighting
   \param color The array in wchich to store the color codes. The first 8 bits are used for fg color, the next 8 bits for bg color.
   \param pos the cursor position. Used for quote matching, etc.
   \param error a list in which a description of each error will be inserted. May be 0, in whcich case no error descriptions will be generated.
*/
void highlight_universal(const wcstring &buffstr, std::vector<highlight_spec_t> &color, size_t pos, wcstring_list_t *error, const env_vars_snapshot_t &vars);

/**
   Translate from HIGHLIGHT_* to FISH_COLOR_* according to environment
   variables. Defaults to FISH_COLOR_NORMAL.

   Example:

   If the environment variable FISH_FISH_COLOR_ERROR is set to 'red', a
   call to highlight_get_color( highlight_error) will return
   FISH_COLOR_RED.
*/
rgb_color_t highlight_get_color(highlight_spec_t highlight, bool is_background);

/** Given a command 'str' from the history, try to determine whether we ought to suggest it by specially recognizing the command.
    Returns true if we validated the command. If so, returns by reference whether the suggestion is valid or not.
*/
bool autosuggest_validate_from_history(const history_item_t &item, file_detection_context_t &detector, const wcstring &working_directory, const env_vars_snapshot_t &vars);

/** Given the command line contents 'str', return via reference a suggestion by specially recognizing the command. The suggestion is escaped. Returns true if we recognized the command (even if we couldn't think of a suggestion for it).
*/
bool autosuggest_suggest_special(const wcstring &str, const wcstring &working_directory, wcstring &outString);

/* Tests whether the specified string cpath is the prefix of anything we could cd to. directories is a list of possible parent directories (typically either the working directory, or the cdpath). This does I/O!

    This is used only internally to this file, and is exposed only for testing.
*/
enum
{
    /* The path must be to a directory */
    PATH_REQUIRE_DIR = 1 << 0,

    /* Expand any leading tilde in the path */
    PATH_EXPAND_TILDE = 1 << 1
};
typedef unsigned int path_flags_t;
bool is_potential_path(const wcstring &const_path, const wcstring_list_t &directories, path_flags_t flags, wcstring *out_path = NULL);

#endif