// Copyright (c) 2017 fd developers
// Licensed under the Apache License, Version 2.0
// <LICENSE-APACHE or http://www.apache.org/licenses/LICENSE-2.0>
// or the MIT license <LICENSE-MIT or http://opensource.org/licenses/MIT>,
// at your option. All files in the project carrying such
// notice may not be copied, modified, or distributed except
// according to those terms.

use std::collections::HashSet;
use std::process;
use std::time;
use std::io::Write;

use exec::CommandTemplate;
use lscolors::LsColors;
use walk::FileType;
use regex_syntax::{Expr, ExprBuilder};

/// Configuration options for *fd*.
pub struct FdOptions {
    /// Whether the search is case-sensitive or case-insensitive.
    pub case_sensitive: bool,

    /// Whether to search within the full file path or just the base name (filename or directory
    /// name).
    pub search_full_path: bool,

    /// Whether to ignore hidden files and directories (or not).
    pub ignore_hidden: bool,

    /// Whether to respect ignore files (`.gitignore`, `.ignore`, ..) or not.
    pub read_ignore: bool,

    /// Whether to respect VCS ignore files (`.gitignore`, ..) or not.
    pub read_gitignore: bool,

    /// Whether to follow symlinks or not.
    pub follow_links: bool,

    /// Whether elements of output should be separated by a null character
    pub null_separator: bool,

    /// The maximum search depth, or `None` if no maximum search depth should be set.
    ///
    /// A depth of `1` includes all files under the current directory, a depth of `2` also includes
    /// all files under subdirectories of the current directory, etc.
    pub max_depth: Option<usize>,

    /// The number of threads to use.
    pub threads: usize,

    /// Time to buffer results internally before streaming to the console. This is useful to
    /// provide a sorted output, in case the total execution time is shorter than
    /// `max_buffer_time`.
    pub max_buffer_time: Option<time::Duration>,

    /// `None` if the output should not be colorized. Otherwise, a `LsColors` instance that defines
    /// how to style different filetypes.
    pub ls_colors: Option<LsColors>,

    /// The type of file to search for. All files other than the specified type will be ignored.
    pub file_types: HashSet<FileType>,

    /// The extension to search for. Only entries matching the extension will be included.
    ///
    /// The value (if present) will be a lowercase string without leading dots.
    pub extensions: Option<HashSet<String>>,

    /// If a value is supplied, each item found will be used to generate and execute commands.
    pub command: Option<CommandTemplate>,

    /// A list of glob patterns that should be excluded from the search.
    pub exclude_patterns: Vec<String>,
}

/// Print error message to stderr and exit with status `1`.
pub fn error(message: &str) -> ! {
    writeln!(&mut ::std::io::stderr(), "{}", message).expect("Failed writing to stderr");
    process::exit(1);
}

/// Determine if a regex pattern contains a literal uppercase character.
pub fn pattern_has_uppercase_char(pattern: &str) -> bool {
    ExprBuilder::new()
        .parse(pattern)
        .map(|expr| expr_has_uppercase_char(&expr))
        .unwrap_or(false)
}

/// Determine if a regex expression contains a literal uppercase character.
fn expr_has_uppercase_char(expr: &Expr) -> bool {
    match *expr {
        Expr::Literal { ref chars, .. } => chars.iter().any(|c| c.is_uppercase()),
        Expr::Class(ref ranges) => ranges
            .iter()
            .any(|r| r.start.is_uppercase() || r.end.is_uppercase()),
        Expr::Group { ref e, .. } | Expr::Repeat { ref e, .. } => expr_has_uppercase_char(e),
        Expr::Concat(ref es) => es.iter().any(expr_has_uppercase_char),
        Expr::Alternate(ref es) => es.iter().any(expr_has_uppercase_char),
        _ => false,
    }
}

/// Exit code representing a general error
pub const EXITCODE_ERROR: i32 = 1;

/// Exit code representing that the process was killed by SIGINT
pub const EXITCODE_SIGINT: i32 = 130;