package main

import (
	"bufio"
	"os"
	"path/filepath"
	"strings"

	"github.com/logrusorgru/aurora"
)

func blacklisted() bool {
	bl, err := blacklistedAux()
	switch {
	case err != nil:
		Warn("failed to check blacklist: ", aurora.Red(err))
		return true
	case bl:
		Warn("skipping git-commit hooks in blacklisted repo")
		return true
	default:
		return false
	}
}

func blacklistedAux() (bool, error) {
	// open the user's blacklist file (and skip if ENOENT)
	home, err := os.UserHomeDir()
	if err != nil {
		return true, err
	}

	f, err := os.Open(filepath.Join(home,
		"git/hooks/pre-commit-blacklist"))
	switch {
	case os.IsNotExist(err):
		return false, nil
	case err != nil:
		return true, err
	}

	// we're called from the root of the git repo
	cwd, err := os.Getwd()
	if err != nil {
		return true, err
	}

	// see if it matches
	scanner := bufio.NewScanner(f)
	for scanner.Scan() {
		// get a line, stripping comments / spaces / blank lines
		bl := scanner.Text()
		if pos := strings.IndexRune(bl, '#'); pos != -1 {
			bl = bl[:pos]
		}
		bl = strings.TrimSpace(bl)
		if bl == "" {
			continue
		}

		// we know bl[0] can be dereferenced
		switch bl[0] {
		case '*':
			return strings.HasSuffix(cwd, bl[1:]), nil

		case '~':
			return cwd == home+bl[1:], nil

		default:
			return cwd == bl, nil
		}
	}
	if scanner.Err() != nil {
		return false, scanner.Err()
	}

	return false, nil
}