// Prototypes for functions for syntax highlighting.
#ifndef FISH_HIGHLIGHT_H
#define FISH_HIGHLIGHT_H

#include <stddef.h>
#include <stdint.h>

#include <vector>

#include "color.h"
#include "common.h"
#include "env.h"

/// Describes the role of a span of text.
enum class highlight_role_t : uint8_t {
    normal = 0,            // normal text
    error,                 // error
    command,               // command
    statement_terminator,  // process separator
    param,                 // command parameter (argument)
    comment,               // comment
    match,                 // matching parenthesis, etc.
    search_match,          // search match
    operat,                // operator
    escape,                // escape sequences
    quote,                 // quoted string
    redirection,           // redirection
    autosuggestion,        // autosuggestion
    selection,

    // Pager support.
    // NOTE: pager.cpp relies on these being in this order.
    pager_progress,
    pager_background,
    pager_prefix,
    pager_completion,
    pager_description,
    pager_secondary_background,
    pager_secondary_prefix,
    pager_secondary_completion,
    pager_secondary_description,
    pager_selected_background,
    pager_selected_prefix,
    pager_selected_completion,
    pager_selected_description,
};

/// Simply value type describing how a character should be highlighted..
struct highlight_spec_t {
    highlight_role_t foreground{highlight_role_t::normal};
    highlight_role_t background{highlight_role_t::normal};
    bool valid_path{false};
    bool force_underline{false};

    highlight_spec_t() = default;

    /* implicit */ highlight_spec_t(highlight_role_t fg,
                                    highlight_role_t bg = highlight_role_t::normal)
        : foreground(fg), background(bg) {}

    bool operator==(const highlight_spec_t &rhs) const {
        return foreground == rhs.foreground && background == rhs.background &&
               valid_path == rhs.valid_path && force_underline == rhs.force_underline;
    }

    bool operator!=(const highlight_spec_t &rhs) const { return !(*this == rhs); }

    static highlight_spec_t make_background(highlight_role_t bg_role) {
        return highlight_spec_t{highlight_role_t::normal, bg_role};
    }
};

class history_item_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 buffstr 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 environment_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 environment_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 buffstr 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 environment_t &vars);

/// \return an RGB color for a given highlight spec.
rgb_color_t highlight_get_color(const 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,
                                       const wcstring &working_directory,
                                       const environment_t &vars);

// 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,
                       const environment_t &vars, path_flags_t flags);

#endif