package cmd

import (
	"gosh/types"
	"regexp"
	"strconv"
	"strings"

	"github.com/fatih/color"
)

func GoshGrep(sh *types.Shell, args map[string]string, input string, regex string) types.CmdOutput {
	re := regexp.MustCompile(regex)
	lines := strings.Split(input, "\n")

	red := color.New(color.FgRed).SprintFunc()

	value, ok := args["-C"]
	var err error
	context_lines := 0

	if ok {
		context_lines, err = strconv.Atoi(value)
		if err != nil {
			return types.CmdOutput{Id: 1, Output: red(err)}
		}
		context_lines++
	}

	var output strings.Builder
	for i, line := range lines {
		if re.MatchString(line) {
			// Print behind
			if context_lines != 0 {
				for bi := i - context_lines; bi < i; bi++ {
					if bi < 0 {
						continue
					} else {
						output.WriteString(lines[bi] + "\n")
					}
				}
			}

			output.WriteString(line + "\n")

			// Print after
			if context_lines != 0 {
				for ai := i + 1; ai < i+context_lines; ai++ {
					if ai > len(lines)-1 {
						continue
					} else {
						output.WriteString(lines[ai] + "\n")
					}
				}
			}
		}
	}

	return types.CmdOutput{Id: 0, Output: output.String()}
}