#!/usr/bin/env bash

set -x

# Log a timestamped message to the console
function log() {
    ts=$(date '+%Y-%m-%dT%H:%M:%SZ')
    printf '%s [bin/deploy] %s\n' "$ts" "$1"
}

# Log an error message to the console and exit
function error() {
    log "$1"
    exit 1
}

# Perform the deployment for a specific chain
function deploy_chain() {
    chain="$1"
    if [ -z "$chain" ]; then
        error "Expected a chain name as the first argument to 'deploy_chain', but did not get one!"
    fi
    chain_index="$2"
    if [ -z "$chain_index" ]; then
        error "Expected a chain index as the second argument to 'deploy_chain', but did not get one!"
    fi

    log "Creating deployment for chain '${chain}'.."

    ts="$(date --utc '+%Y-%m-%dT%H:%M:%SZ')"

    app="${PREFIX}-explorer"
    bucket="${PREFIX}-explorer-codedeploy-releases"
    release_name="${CIRCLE_SHA1}_${CIRCLE_BUILD_NUM}"

    log "Pushing new revision to CodeDeploy app '${app}' in S3 bucket '${bucket}', as '${release_name}.zip'.."

    aws deploy push \
        --description="${PREFIX} release at commit ${CIRCLE_SHA1} via build ${CIRCLE_BUILD_NUM} at ${ts}" \
        --application-name="${app}" \
        --s3-location="s3://${bucket}/${release_name}.zip" \
        --source=./

    log "Push successful!"

    deploy_config="CodeDeployDefault.OneAtATime"
    deploy_group="${PREFIX}-explorer-dg${chain_index}"

    log "Creating deployment for CodeDeploy app '${app}', using deployment config ${deploy_config}, and group ${deploy_group}"

    aws create-deployment \
        --description="${PREFIX} deployment of commit ${CIRCLE_SHA1} via build ${CIRCLE_BUILD_NUM} at ${ts}" \
        --application-name="${app}" \
        --deployment-config-name="${deploy_config}" \
        --deployment-group-name="${deploy_group}" \
        --s3-location="bucket=${bucket},key=${release_name}.zip,bundleType=zip"

    log 'Deployment successfully created!'
    log 'You may check deploy progress via the AWS Console or AWS CLI using the deployment ID shown above.'

    return 0
}

# Make sure we got an environment as an argument to this script
DEPLOY_ENV="${1:-$CIRCLE_BRANCH}"
if [ -z "$DEPLOY_ENV" ]; then
    error "Expected deployment environment as an argument or via \$CIRCLE_BRANCH, but neither was provided!"
fi
# Strip deploy- prefix if one was set and convert it
# to uppercase for environment variable lookups
DEPLOY_ENV="$(echo "$DEPLOY_ENV" | sed -e 's/^deploy-//' | tr '[:lower:]' '[:upper:]')"

log "Deploying to environment '${DEPLOY_ENV}'"

# Make sure we have credentials set
log "Verifying credentials.."
if [ -z "$AWS_ACCESS_KEY_ID" ] || [ -z "$AWS_SECRET_ACCESS_KEY" ]; then
    error "Unable to perform deploy: missing AWS credentials!"
fi

# Lookup the infrastructure prefix for the target system in the environment
log "Verifying infrastructure prefix.."
PREFIX_VAR="AWS_${DEPLOY_ENV}_PREFIX"
PREFIX="${!PREFIX_VAR}"
if [ -z "$PREFIX" ]; then
    error "Unknown deploy environment '$DEPLOY_ENV', or AWS_${DEPLOY_ENV}_PREFIX is unset!"
    exit 1
fi

# Lookup the list of chains for the target system in the environment
log "Verifying deployment groups.."
CHAINS_VAR="AWS_${DEPLOY_ENV}_CHAINS"
CHAINS="${!CHAINS_VAR}"
if [ -z "$CHAINS" ]; then
    error "AWS_${DEPLOY_ENV}_CHAINS is unset!"
fi

# Convert the comma-separated list of names into a newline-separated list of names
CHAINS="$(echo "$CHAINS" | tr ',' '\n')"

# Install AWS CLI
if ! which aws >/dev/null; then
    log "Installing AWS CLI.."
    mkdir -p ~/bin
    wget "https://s3.amazonaws.com/aws-cli/awscli-bundle.zip"
    unzip awscli-bundle.zip
    ./awscli-bundle/install -b ~/bin/aws
    export PATH=$HOME/bin:$PATH
    log "Install completed successfully!"
fi

# For each chain perform a deployment
i=0
for chain in $CHAINS; do
    deploy_chain "$chain" "$i"
    i=$((i+1))
done

log "Deployment task has succesfully completed!"
exit 0