###################################
#                                 #
#          CONFIGURATION          #
#                                 #
###################################

########## Shell/Terminal Settings ##########
SHELL := /bin/bash

# determine if make is being executed from interactive terminal
INTERACTIVE:=$(shell [ -t 0 ] && echo 1)

# Use Go Modules for everything
export GO111MODULE=on

########## Tags ##########

# get git tag
GIT_TAG   ?= $(shell git describe --tags)
ifeq ($(GIT_TAG),)
GIT_TAG   := $(shell git describe --always)
endif

# Docker image tag derived from Git tag
K3D_IMAGE_TAG := $(GIT_TAG)

# get latest k3s version: grep the tag and replace + with - (difference between git and dockerhub tags)
K3S_TAG		:= $(shell curl --silent "https://update.k3s.io/v1-release/channels/stable" | egrep -o '/v[^ ]+"' | sed -E 's/\/|\"//g' | sed -E 's/\+/\-/')

ifeq ($(K3S_TAG),)
$(warning K3S_TAG undefined: couldn't get latest k3s image tag!)
$(warning Output of curl: $(shell curl --silent "https://update.k3s.io/v1-release/channels/stable"))
$(error exiting)
endif

########## Source Options ##########
# DIRS defines a single level directly, we only look at *.go in this directory.
# REC_DIRS defines a source code tree. All go files are analyzed recursively.
DIRS :=  .
REC_DIRS := cmd

########## Test Settings ##########
E2E_LOG_LEVEL ?= WARN
E2E_SKIP ?=
E2E_RUNNER_START_TIMEOUT ?= 10

########## Go Build Options ##########
# Build targets
TARGETS ?= darwin/amd64 linux/amd64 linux/386 linux/arm linux/arm64 windows/amd64
TARGET_OBJS ?= darwin-amd64.tar.gz darwin-amd64.tar.gz.sha256 linux-amd64.tar.gz linux-amd64.tar.gz.sha256 linux-386.tar.gz linux-386.tar.gz.sha256 linux-arm.tar.gz linux-arm.tar.gz.sha256 linux-arm64.tar.gz linux-arm64.tar.gz.sha256 windows-amd64.zip windows-amd64.zip.sha256

# Go options
GO        ?= go
PKG       := $(shell go mod vendor)
TAGS      :=
TESTS     := .
TESTFLAGS :=
LDFLAGS   := -w -s -X github.com/rancher/k3d/v3/version.Version=${GIT_TAG} -X github.com/rancher/k3d/v3/version.K3sVersion=${K3S_TAG}
GCFLAGS   := 
GOFLAGS   :=
BINDIR    := $(CURDIR)/bin
BINARIES  := k3d

# Rules for finding all go source files using 'DIRS' and 'REC_DIRS'
GO_SRC := $(foreach dir,$(DIRS),$(wildcard $(dir)/*.go))
GO_SRC += $(foreach dir,$(REC_DIRS),$(shell find $(dir) -name "*.go"))

########## Required Tools ##########
# Go Package required
PKG_GOX := github.com/mitchellh/gox@v1.0.1
PKG_GOLANGCI_LINT_VERSION := 1.28.3
PKG_GOLANGCI_LINT_SCRIPT := https://raw.githubusercontent.com/golangci/golangci-lint/master/install.sh
PKG_GOLANGCI_LINT := github.com/golangci/golangci-lint/cmd/golangci-lint@v${PKG_GOLANGCI_LINT_VERSION}

########## Linting Options ##########
# configuration adjustments for golangci-lint
GOLANGCI_LINT_DISABLED_LINTERS := "" # disabling typecheck, because it currently (06.09.2019) fails with Go 1.13

# Rules for directory list as input for the golangci-lint program
LINT_DIRS := $(DIRS) $(foreach dir,$(REC_DIRS),$(dir)/...)

#############################
#                           #
#          TARGETS          #
#                           #
#############################

.PHONY: all build build-cross clean fmt check-fmt lint check extra-clean install-tools

all: clean fmt check build

############################
########## Builds ##########
############################

# debug builds
build-debug: GCFLAGS+="all=-N -l"
build-debug: build

# default build target for the local platform
build:
	CGO_ENABLED=0 $(GO) build $(GOFLAGS) -tags '$(TAGS)' -ldflags '$(LDFLAGS)' -gcflags '$(GCFLAGS)' -o '$(BINDIR)/$(BINARIES)'

# cross-compilation for all targets
build-cross: LDFLAGS += -extldflags "-static"
build-cross:
	CGO_ENABLED=0 gox -parallel=3 -output="_dist/$(BINARIES)-{{.OS}}-{{.Arch}}" -osarch='$(TARGETS)' $(GOFLAGS) $(if $(TAGS),-tags '$(TAGS)',) -ldflags '$(LDFLAGS)'

# build a specific docker target ( '%' matches the target as specified in the Dockerfile)
build-docker-%:
	@echo "Building Docker image k3d:$(K3D_IMAGE_TAG)-$*"
	docker build . -t k3d:$(K3D_IMAGE_TAG)-$* --target $*

# build helper images
build-helper-images:
	@echo "Building docker image rancher/k3d-proxy:$(GIT_TAG)"
	docker build proxy/ -f proxy/Dockerfile -t rancher/k3d-proxy:$(GIT_TAG)
	@echo "Building docker image rancher/k3d-tools:$(GIT_TAG)"
	docker build --no-cache tools/ -f tools/Dockerfile -t rancher/k3d-tools:$(GIT_TAG) --build-arg GIT_TAG=$(GIT_TAG)

##############################
########## Cleaning ##########
##############################

clean:
	@rm -rf $(BINDIR) _dist/

extra-clean: clean
	$(GO) clean -i $(PKG_GOX)
	$(GO) clean -i $(PKG_GOLANGCI_LINT)

##########################################
########## Formatting & Linting ##########
##########################################

# fmt will fix the golang source style in place.
fmt:
	@gofmt -s -l -w $(GO_SRC)

# check-fmt returns an error code if any source code contains format error.
check-fmt:
	@test -z $(shell gofmt -s -l $(GO_SRC) | tee /dev/stderr) || echo "[WARN] Fix formatting issues with 'make fmt'"

lint:
	@golangci-lint run -D $(GOLANGCI_LINT_DISABLED_LINTERS) $(LINT_DIRS)

check: check-fmt lint

###########################
########## Tests ##########
###########################

e2e: build-docker-dind
	@echo "Running e2e tests in k3d:$(K3D_IMAGE_TAG)"
	LOG_LEVEL="$(E2E_LOG_LEVEL)" E2E_SKIP="$(E2E_SKIP)" E2E_RUNNER_START_TIMEOUT=$(E2E_RUNNER_START_TIMEOUT) tests/dind.sh "${K3D_IMAGE_TAG}-dind"

ci-tests: fmt check e2e

##########################
########## Misc ##########
##########################

drone:
	@echo "Running drone pipeline locally with branch=master and event=push"
	drone exec --trusted --branch master --event push

#########################################
########## Setup & Preparation ##########
#########################################

# Check for required executables
HAS_GOX := $(shell command -v gox 2> /dev/null)
HAS_GOLANGCI  := $(shell command -v golangci-lint)
HAS_GOLANGCI_VERSION := $(shell golangci-lint --version | grep "version $(PKG_GOLANGCI_LINT_VERSION) " 2>&1)

install-tools:
ifndef HAS_GOX
	($(GO) get $(PKG_GOX))
endif
ifndef HAS_GOLANGCI
	(curl -sfL $(PKG_GOLANGCI_LINT_SCRIPT) | sh -s -- -b ${GOPATH}/bin v${PKG_GOLANGCI_LINT_VERSION})
endif
ifdef HAS_GOLANGCI
ifeq ($(HAS_GOLANGCI_VERSION),)
ifdef INTERACTIVE
	@echo "Warning: Your installed version of golangci-lint (interactive: ${INTERACTIVE}) differs from what we'd like to use. Switch to v${PKG_GOLANGCI_LINT_VERSION}? [Y/n]"
	@read line; if [ $$line == "y" ]; then (curl -sfL $(PKG_GOLANGCI_LINT_SCRIPT) | sh -s -- -b ${GOPATH}/bin v${PKG_GOLANGCI_LINT_VERSION}); fi
else
	@echo "Warning: you're not using the same version of golangci-lint as us (v${PKG_GOLANGCI_LINT_VERSION})"
endif
endif
endif

# In the CI system, we need...
# - golangci-lint for linting (lint)
# - gox for cross-compilation (build-cross)
# - kubectl for E2E-tests (e2e)
ci-setup:
	@echo "Installing Go tools..."
	curl -sfL $(PKG_GOLANGCI_LINT_SCRIPT) | sh -s -- -b ${GOPATH}/bin v$(PKG_GOLANGCI_LINT_VERSION)
	go get $(PKG_GOX)

	@echo "Installing kubectl..."
	curl -LO https://storage.googleapis.com/kubernetes-release/release/`curl -s https://storage.googleapis.com/kubernetes-release/release/stable.txt`/bin/linux/amd64/kubectl
	chmod +x ./kubectl
	mv ./kubectl /usr/local/bin/kubectl