#!/bin/bash
# post-receive hook to push-deploy into a git repo.
#
# Deploy by pushing $DEPLOY_BRANCH.
# Rollback by force-pushing into the branch.
#
# 1. Setup your git repo:
#
#       git init --bare
#
# 2. Put this hook script in hooks/post-receive
# 3. Make as many worktree target dirs as you want and configure
#    `which_worktree` and `deploy` below accordingly. Such as...
#
#       mkdir -p ../branches/{master,staging}/src
#
# 4. Push to the repo and the appropriate worktree will be deployed.
#
# Enjoy.

##
# Override these:

function which_worktree() {
    # Given a branch name, print the expected path of the worktree.
    # If the path does not exist, deployment will be skipped for the branch.
    branch="$1"
    if [ "$branch" == "master" ]; then
        echo "../app/src"
    fi
}

function deploy() {
    # Given a branch name and worktree path, perform desired deployment steps.
    branch="$1"
    worktree="$2"

    container_id="XXX"
    docker run -volumes-from "${container_id}" -i uwsgi bash -c "source /app/env/bin/activate && cd /app/src && make -e 'INI_FILE=production.ini' && touch .reload"

    if docker ps | grep -q "${container_id}"; then
        echo -e "${CGREEN}Server is happy. :)${CNONE}"
    else
        echo -e "${CRED}SERVER IS DOWN! Recent log:${CYELLOW}"
        docker logs "${container_id}" | tail -n 40
        echo -en "$CNONE"}
    fi
}

##
# The meaty logic that shouldn't need touching:

# Symbol and color shortcuts, borrowed from Gitolite-Hooks <3
BLANK=$(echo -e "\e[1G        ")
ARROW=$(echo -e "\e[1G------> ")
CNONE=$(echo -e "\e[00m")
CBLACK=$(echo -e "\e[1;30m")
CWHITE=$(echo -e "\e[0;37m")
CGREEN=$(echo -e "\e[1;32m")
CBLUE=$(echo -e "\e[1;34m")
CRED=$(echo -e "\e[1;31m")
CYELLOW=$(echo -e "\e[1;33m")

function prefix() {
    sed "s/^/$@/"
}

if [ "$1" ]; then
    branch="$1"
    worktree="$(which_worktree $branch)"

    echo -e "${ARROW}${CBLUE}Manual deploy on branch:${CNONE} ${branch}"
    if [ ! -d "$worktree" ]; then
        echo -e "${BLANK}Worktree does not exist, skipping: ${worktree}"
        exit 1;
    fi

    git --work-tree="$worktree" checkout -q -f "$branch"

    echo -en "${CWHITE}"
    deploy "$branch" "$worktree" | prefix "${BLANK}"
    echo -en "${CNONE}"

    exit 0;
fi

while read oldrev newrev ref; do
    branch="$(echo $ref | cut -d '/' -f3)"
    echo "${ARROW}Received branch: ${branch}"
    worktree="$(which_worktree $branch)"

    if [ "$worktree" ] && [ -d "$worktree" ]; then
        echo "${ARROW}${CBLUE}Deploying branch:${CNONE} ${branch}"
        cd "$GIT_DIR"
        git --work-tree="$worktree" checkout -q -f "$branch"

        echo -en "${CWHITE}"
        deploy "$branch" "$worktree" | prefix "${BLANK}"
        echo -en "${CNONE}"
    fi
done