#!/usr/bin/env julia

const patterns = split("""
    *.1
    *.c
    *.cpp
    *.h
    *.inc
    *.jl
    *.lsp
    *.make
    *.md
    *.mk
    *.rst
    *.scm
    *.sh
    *.yml
    *Makefile
""")

const errors = Set{Tuple{String,Int,String}}()

for path in eachline(`git ls-files -- $patterns`)
    lineno = 0
    non_blank = 0

    file_err(msg) = push!(errors, (path, 0, msg))
    line_err(msg) = push!(errors, (path, lineno, msg))

    for line in eachline(path, keep=true)
        lineno += 1
        contains(line, '\r')   && file_err("non-UNIX line endings")
        contains(line, '\ua0') && line_err("non-breaking space")
        endswith(line, '\n')   || line_err("no trailing newline")
        line = chomp(line)
        endswith(line, r"\s")  && line_err("trailing whitespace")
        contains(line, r"\S")  && (non_blank = lineno)
    end
    non_blank < lineno         && line_err("trailing blank lines")
end

if isempty(errors)
    println(stderr, "Whitespace check found no issues.")
    exit(0)
else
    println(stderr, "Whitespace check found $(length(errors)) issues:")
    for (path, lineno, msg) in sort!(collect(errors))
        if lineno == 0
            println(stderr, "$path -- $msg")
        else
            println(stderr, "$path:$lineno -- $msg")
        end
    end
    exit(1)
end