#!/usr/bin/env bash

remote=${1:-""}
branch=""
filename=${2:-""}
line1=${3:-""}
line2=${4:-""}

# get remote name
if [[ $remote == "" ]]; then
    branch="$(git rev-parse --abbrev-ref HEAD 2>/dev/null)"
    remote=$(git config branch."${branch}".remote || echo "origin")
fi

if [[ $remote == "" ]]; then
    echo "Remote not found"
    exit 1
fi

remote_url=$(git remote get-url "$remote") || exit $?

if [[ $remote_url = git@* ]]; then
    url=$(echo "$remote_url" | sed -E -e 's/:/\//' -e 's/\.git$//' -e 's/.*@(.*)/http:\/\/\1/')
elif [[ $remote_url = http* ]]; then
    url=${remote_url%.git}
fi

# construct urls
commit_hash=$(git rev-parse HEAD 2>/dev/null)
commit_or_branch=${commit_hash:-${branch}}

if [[ $remote_url =~ gitlab ]]; then
    # construct gitlab urls
    # https://gitlab.com/<user_or_group>/<repo>/-/blob/<commit_or_branch>/<filename>#L<line1>-<line2>
    if [[ -n ${filename} ]]; then
        url="${url}/-/blob/${commit_or_branch}/${filename}"
        if [[ -n "${line1}" ]]; then
            url="${url}#L${line1}"
            if [[ -n "${line2}" ]]; then
                url="${url}-${line2}"
            fi
        fi
    fi
elif [[ $remote_url =~ github ]]; then
    # construct github urls
    # https://github.com/<user_or_org>/<repo>/blob/<commit_or_branch>/<filename>#L<line1>-L<line2>
    if [[ -n "${filename}" ]]; then
        url="${url}/blob/${commit_or_branch}/${filename}"
        if [[ -n "${line1}" ]]; then
            url="${url}#L${line1}"
            if [[ -n "${line2}" ]]; then
                url="${url}-L${line2}"
            fi
        fi
    fi
elif [[ $remote_url =~ bitbucket ]]; then
    # construct bitbucket urls
    # https://bitbucket.org/<user_or_org>/<repo>/src/<commit_or_branch>/<filename>#lines-<line1>:<line2>
    if [[ -n ${filename} ]]; then
        url=${url}/src/${commit_or_branch}/${filename}
        if [[ -n "${line1}" ]]; then
            url="${url}#lines-${line1}"
            if [[ -n "${line2}" ]]; then
                url="${url}:${line2}"
            fi
        fi
    fi
fi

# open url
case "$OSTYPE" in
darwin*)
    # MacOS
    open "$url"
    ;;
msys)
    # Git-Bash on Windows
    start "$url"
    ;;
linux*)
    # Handle WSL on Windows
    if uname -a | grep -i -q Microsoft && command -v powershell.exe; then
        powershell.exe -NoProfile start "$url"
    else
        xdg-open "$url"
    fi
    ;;
*)
    # fall back to xdg-open for BSDs, etc.
    xdg-open "$url"
    ;;
esac