/*
   Copyright 2020 Docker Compose CLI authors

   Licensed under the Apache License, Version 2.0 (the "License");
   you may not use this file except in compliance with the License.
   You may obtain a copy of the License at

       http://www.apache.org/licenses/LICENSE-2.0

   Unless required by applicable law or agreed to in writing, software
   distributed under the License is distributed on an "AS IS" BASIS,
   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   See the License for the specific language governing permissions and
   limitations under the License.
*/

package compose

import (
	"context"
	"fmt"
	"os"
	"os/signal"
	"path/filepath"
	"strconv"
	"strings"
	"syscall"

	"github.com/docker/compose-cli/api/client"
	"github.com/docker/compose-cli/api/compose"
	"github.com/docker/compose-cli/api/context/store"
	"github.com/docker/compose-cli/api/progress"
	"github.com/docker/compose-cli/cli/cmd"
	"github.com/docker/compose-cli/cli/formatter"

	"github.com/compose-spec/compose-go/types"
	"github.com/sirupsen/logrus"
	"github.com/spf13/cobra"
)

// composeOptions hold options common to `up` and `run` to run compose project
type composeOptions struct {
	*projectOptions
	Build bool
	// ACI only
	DomainName string
}

type upOptions struct {
	*composeOptions
	Detach        bool
	Environment   []string
	removeOrphans bool
	forceRecreate bool
	noRecreate    bool
	noStart       bool
	cascadeStop   bool
	exitCodeFrom  string
	scale         []string
}

func (o upOptions) recreateStrategy() string {
	if o.noRecreate {
		return compose.RecreateNever
	}
	if o.forceRecreate {
		return compose.RecreateForce
	}
	return compose.RecreateDiverged
}

func upCommand(p *projectOptions, contextType string) *cobra.Command {
	opts := upOptions{
		composeOptions: &composeOptions{
			projectOptions: p,
		},
	}
	upCmd := &cobra.Command{
		Use:   "up [SERVICE...]",
		Short: "Create and start containers",
		RunE: func(cmd *cobra.Command, args []string) error {
			switch contextType {
			case store.LocalContextType, store.DefaultContextType, store.EcsLocalSimulationContextType:
				if opts.exitCodeFrom != "" {
					opts.cascadeStop = true
				}
				if opts.cascadeStop && opts.Detach {
					return fmt.Errorf("--abort-on-container-exit and --detach are incompatible")
				}
				if opts.forceRecreate && opts.noRecreate {
					return fmt.Errorf("--force-recreate and --no-recreate are incompatible")
				}
				return runCreateStart(cmd.Context(), opts, args)
			default:
				return runUp(cmd.Context(), opts, args)
			}
		},
	}
	flags := upCmd.Flags()
	flags.StringArrayVarP(&opts.Environment, "environment", "e", []string{}, "Environment variables")
	flags.BoolVarP(&opts.Detach, "detach", "d", false, "Detached mode: Run containers in the background")
	flags.BoolVar(&opts.Build, "build", false, "Build images before starting containers.")
	flags.BoolVar(&opts.removeOrphans, "remove-orphans", false, "Remove containers for services not defined in the Compose file.")
	flags.StringArrayVar(&opts.scale, "scale", []string{}, "Scale SERVICE to NUM instances. Overrides the `scale` setting in the Compose file if present.")

	switch contextType {
	case store.AciContextType:
		flags.StringVar(&opts.DomainName, "domainname", "", "Container NIS domain name")
	case store.LocalContextType, store.DefaultContextType, store.EcsLocalSimulationContextType:
		flags.BoolVar(&opts.forceRecreate, "force-recreate", false, "Recreate containers even if their configuration and image haven't changed.")
		flags.BoolVar(&opts.noRecreate, "no-recreate", false, "If containers already exist, don't recreate them. Incompatible with --force-recreate.")
		flags.BoolVar(&opts.noStart, "no-start", false, "Don't start the services after creating them.")
		flags.BoolVar(&opts.cascadeStop, "abort-on-container-exit", false, "Stops all containers if any container was stopped. Incompatible with -d")
		flags.StringVar(&opts.exitCodeFrom, "exit-code-from", "", "Return the exit code of the selected service container. Implies --abort-on-container-exit")
	}

	return upCmd
}

func runUp(ctx context.Context, opts upOptions, services []string) error {
	c, project, err := setup(ctx, *opts.composeOptions, services)
	if err != nil {
		return err
	}

	err = applyScaleOpt(opts.scale, project)
	if err != nil {
		return err
	}

	_, err = progress.Run(ctx, func(ctx context.Context) (string, error) {
		return "", c.ComposeService().Up(ctx, project, compose.UpOptions{
			Detach: opts.Detach,
		})
	})
	return err
}

func runCreateStart(ctx context.Context, opts upOptions, services []string) error {
	c, project, err := setup(ctx, *opts.composeOptions, services)
	if err != nil {
		return err
	}

	err = applyScaleOpt(opts.scale, project)
	if err != nil {
		return err
	}

	if opts.exitCodeFrom != "" {
		_, err := project.GetService(opts.exitCodeFrom)
		if err != nil {
			return err
		}
	}

	_, err = progress.Run(ctx, func(ctx context.Context) (string, error) {
		err := c.ComposeService().Create(ctx, project, compose.CreateOptions{
			RemoveOrphans: opts.removeOrphans,
			Recreate:      opts.recreateStrategy(),
		})
		if err != nil {
			return "", err
		}
		if opts.Detach {
			err = c.ComposeService().Start(ctx, project, compose.StartOptions{})
		}
		return "", err
	})
	if err != nil {
		return err
	}

	if opts.noStart {
		return nil
	}

	if opts.Detach {
		return nil
	}

	queue := make(chan compose.ContainerEvent)
	printer := printer{
		queue: queue,
	}

	stopFunc := func() error {
		ctx := context.Background()
		_, err := progress.Run(ctx, func(ctx context.Context) (string, error) {
			return "", c.ComposeService().Stop(ctx, project)
		})
		return err
	}
	signalChan := make(chan os.Signal, 1)
	signal.Notify(signalChan, syscall.SIGINT, syscall.SIGTERM)
	go func() {
		<-signalChan
		fmt.Println("Gracefully stopping...")
		stopFunc() // nolint:errcheck
	}()

	err = c.ComposeService().Start(ctx, project, compose.StartOptions{
		Attach: func(event compose.ContainerEvent) {
			queue <- event
		},
	})
	if err != nil {
		return err
	}

	exitCode, err := printer.run(ctx, opts.cascadeStop, opts.exitCodeFrom, stopFunc)
	if exitCode != 0 {
		return cmd.ExitCodeError{ExitCode: exitCode}
	}
	return err
}

func applyScaleOpt(opts []string, project *types.Project) error {
	for _, scale := range opts {
		split := strings.Split(scale, "=")
		if len(split) != 2 {
			return fmt.Errorf("invalid --scale option %q. Should be SERVICE=NUM", scale)
		}
		name := split[0]
		replicas, err := strconv.Atoi(split[1])
		if err != nil {
			return err
		}
		err = setServiceScale(project, name, replicas)
		if err != nil {
			return err
		}
	}
	return nil
}

func setServiceScale(project *types.Project, name string, replicas int) error {
	for i, s := range project.Services {
		if s.Name == name {
			service, err := project.GetService(name)
			if err != nil {
				return err
			}
			if service.Deploy == nil {
				service.Deploy = &types.DeployConfig{}
			}
			count := uint64(replicas)
			service.Deploy.Replicas = &count
			project.Services[i] = service
			return nil
		}
	}
	return fmt.Errorf("unknown service %q", name)
}

func setup(ctx context.Context, opts composeOptions, services []string) (*client.Client, *types.Project, error) {
	c, err := client.NewWithDefaultLocalBackend(ctx)
	if err != nil {
		return nil, nil, err
	}

	project, err := opts.toProject(services)
	if err != nil {
		return nil, nil, err
	}

	if opts.DomainName != "" {
		// arbitrarily set the domain name on the first service ; ACI backend will expose the entire project
		project.Services[0].DomainName = opts.DomainName
	}
	if opts.Build {
		for _, service := range project.Services {
			service.PullPolicy = types.PullPolicyBuild
		}
	}
	if opts.EnvFile != "" {
		var services types.Services
		for _, s := range project.Services {
			ef := opts.EnvFile
			if ef != "" {
				if !filepath.IsAbs(ef) {
					ef = filepath.Join(project.WorkingDir, opts.EnvFile)
				}
				if s.Labels == nil {
					s.Labels = make(map[string]string)
				}
				s.Labels[compose.EnvironmentFileLabel] = ef
				services = append(services, s)
			}
		}
		project.Services = services
	}

	return c, project, nil
}

type printer struct {
	queue chan compose.ContainerEvent
}

func (p printer) run(ctx context.Context, cascadeStop bool, exitCodeFrom string, stopFn func() error) (int, error) { //nolint:unparam
	consumer := formatter.NewLogConsumer(ctx, os.Stdout)
	var aborting bool
	for {
		event := <-p.queue
		switch event.Type {
		case compose.ContainerEventExit:
			if !aborting {
				consumer.Status(event.Service, event.Source, fmt.Sprintf("exited with code %d", event.ExitCode))
			}
			if cascadeStop && !aborting {
				aborting = true
				fmt.Println("Aborting on container exit...")
				err := stopFn()
				if err != nil {
					return 0, err
				}
			}
			if exitCodeFrom == "" || exitCodeFrom == event.Service {
				logrus.Error(event.ExitCode)
				return event.ExitCode, nil
			}
		case compose.ContainerEventLog:
			if !aborting {
				consumer.Log(event.Service, event.Source, event.Line)
			}
		}
	}
}