package events

import (
	"fmt"
	"os"
	"path/filepath"
	"sort"
	"strings"

	"github.com/uber-go/tally"

	"github.com/runatlantis/atlantis/server/core/config/valid"
	"github.com/runatlantis/atlantis/server/core/terraform"
	"github.com/runatlantis/atlantis/server/logging"
	"github.com/runatlantis/atlantis/server/metrics"

	"github.com/pkg/errors"

	"github.com/runatlantis/atlantis/server/core/config"
	"github.com/runatlantis/atlantis/server/events/command"
	"github.com/runatlantis/atlantis/server/events/vcs"
)

const (
	// DefaultRepoRelDir is the default directory we run commands in, relative
	// to the root of the repo.
	DefaultRepoRelDir = "."
	// DefaultWorkspace is the default Terraform workspace we run commands in.
	// This is also Terraform's default workspace.
	DefaultWorkspace = "default"
	// DefaultAutomergeEnabled is the default for the automerge setting.
	DefaultAutomergeEnabled = false
	// DefaultParallelApplyEnabled is the default for the parallel apply setting.
	DefaultParallelApplyEnabled = false
	// DefaultParallelPlanEnabled is the default for the parallel plan setting.
	DefaultParallelPlanEnabled = false
	// DefaultDeleteSourceBranchOnMerge being false is the default setting whether or not to remove a source branch on merge
	DefaultDeleteSourceBranchOnMerge = false
)

func NewInstrumentedProjectCommandBuilder(
	policyChecksSupported bool,
	parserValidator *config.ParserValidator,
	projectFinder ProjectFinder,
	vcsClient vcs.Client,
	workingDir WorkingDir,
	workingDirLocker WorkingDirLocker,
	globalCfg valid.GlobalCfg,
	pendingPlanFinder *DefaultPendingPlanFinder,
	commentBuilder CommentBuilder,
	skipCloneNoChanges bool,
	EnableRegExpCmd bool,
	AutoDetectModuleFiles string,
	AutoplanFileList string,
	RestrictFileList bool,
	scope tally.Scope,
	logger logging.SimpleLogging,
	terraformClient terraform.Client,
) *InstrumentedProjectCommandBuilder {
	scope = scope.SubScope("builder")

	for _, m := range []string{metrics.ExecutionSuccessMetric, metrics.ExecutionErrorMetric} {
		metrics.InitCounter(scope, m)
	}

	return &InstrumentedProjectCommandBuilder{
		ProjectCommandBuilder: NewProjectCommandBuilder(
			policyChecksSupported,
			parserValidator,
			projectFinder,
			vcsClient,
			workingDir,
			workingDirLocker,
			globalCfg,
			pendingPlanFinder,
			commentBuilder,
			skipCloneNoChanges,
			EnableRegExpCmd,
			AutoDetectModuleFiles,
			AutoplanFileList,
			RestrictFileList,
			scope,
			logger,
			terraformClient,
		),
		Logger: logger,
		scope:  scope,
	}
}

func NewProjectCommandBuilder(
	policyChecksSupported bool,
	parserValidator *config.ParserValidator,
	projectFinder ProjectFinder,
	vcsClient vcs.Client,
	workingDir WorkingDir,
	workingDirLocker WorkingDirLocker,
	globalCfg valid.GlobalCfg,
	pendingPlanFinder *DefaultPendingPlanFinder,
	commentBuilder CommentBuilder,
	skipCloneNoChanges bool,
	EnableRegExpCmd bool,
	AutoDetectModuleFiles string,
	AutoplanFileList string,
	RestrictFileList bool,
	scope tally.Scope,
	logger logging.SimpleLogging,
	terraformClient terraform.Client,
) *DefaultProjectCommandBuilder {
	return &DefaultProjectCommandBuilder{
		ParserValidator:       parserValidator,
		ProjectFinder:         projectFinder,
		VCSClient:             vcsClient,
		WorkingDir:            workingDir,
		WorkingDirLocker:      workingDirLocker,
		GlobalCfg:             globalCfg,
		PendingPlanFinder:     pendingPlanFinder,
		SkipCloneNoChanges:    skipCloneNoChanges,
		EnableRegExpCmd:       EnableRegExpCmd,
		AutoDetectModuleFiles: AutoDetectModuleFiles,
		AutoplanFileList:      AutoplanFileList,
		RestrictFileList:      RestrictFileList,
		ProjectCommandContextBuilder: NewProjectCommandContextBuilder(
			policyChecksSupported,
			commentBuilder,
			scope,
		),
		TerraformExecutor: terraformClient,
	}
}

type ProjectPlanCommandBuilder interface {
	// BuildAutoplanCommands builds project commands that will run plan on
	// the projects determined to be modified.
	BuildAutoplanCommands(ctx *command.Context) ([]command.ProjectContext, error)
	// BuildPlanCommands builds project plan commands for this ctx and comment. If
	// comment doesn't specify one project then there may be multiple commands
	// to be run.
	BuildPlanCommands(ctx *command.Context, comment *CommentCommand) ([]command.ProjectContext, error)
}

type ProjectApplyCommandBuilder interface {
	// BuildApplyCommands builds project Apply commands for this ctx and comment. If
	// comment doesn't specify one project then there may be multiple commands
	// to be run.
	BuildApplyCommands(ctx *command.Context, comment *CommentCommand) ([]command.ProjectContext, error)
}

type ProjectApprovePoliciesCommandBuilder interface {
	// BuildApprovePoliciesCommands builds project PolicyCheck commands for this ctx and comment.
	BuildApprovePoliciesCommands(ctx *command.Context, comment *CommentCommand) ([]command.ProjectContext, error)
}

type ProjectVersionCommandBuilder interface {
	// BuildVersionCommands builds project Version commands for this ctx and comment. If
	// comment doesn't specify one project then there may be multiple commands
	// to be run.
	BuildVersionCommands(ctx *command.Context, comment *CommentCommand) ([]command.ProjectContext, error)
}

type ProjectImportCommandBuilder interface {
	// BuildImportCommands builds project Import commands for this ctx and comment. If
	// comment doesn't specify one project then there may be multiple commands
	// to be run.
	BuildImportCommands(ctx *command.Context, comment *CommentCommand) ([]command.ProjectContext, error)
}

//go:generate pegomock generate -m --package mocks -o mocks/mock_project_command_builder.go ProjectCommandBuilder

// ProjectCommandBuilder builds commands that run on individual projects.
type ProjectCommandBuilder interface {
	ProjectPlanCommandBuilder
	ProjectApplyCommandBuilder
	ProjectApprovePoliciesCommandBuilder
	ProjectVersionCommandBuilder
	ProjectImportCommandBuilder
}

// DefaultProjectCommandBuilder implements ProjectCommandBuilder.
// This class combines the data from the comment and any atlantis.yaml file or
// Atlantis server config and then generates a set of contexts.
type DefaultProjectCommandBuilder struct {
	ParserValidator              *config.ParserValidator
	ProjectFinder                ProjectFinder
	VCSClient                    vcs.Client
	WorkingDir                   WorkingDir
	WorkingDirLocker             WorkingDirLocker
	GlobalCfg                    valid.GlobalCfg
	PendingPlanFinder            *DefaultPendingPlanFinder
	ProjectCommandContextBuilder ProjectCommandContextBuilder
	SkipCloneNoChanges           bool
	EnableRegExpCmd              bool
	AutoDetectModuleFiles        string
	AutoplanFileList             string
	EnableDiffMarkdownFormat     bool
	RestrictFileList             bool
	TerraformExecutor            terraform.Client
}

// See ProjectCommandBuilder.BuildAutoplanCommands.
func (p *DefaultProjectCommandBuilder) BuildAutoplanCommands(ctx *command.Context) ([]command.ProjectContext, error) {
	projCtxs, err := p.buildAllCommandsByCfg(ctx, command.Plan, nil, false)
	if err != nil {
		return nil, err
	}
	var autoplanEnabled []command.ProjectContext
	for _, projCtx := range projCtxs {
		if !projCtx.AutoplanEnabled {
			ctx.Log.Debug("ignoring project at dir %q, workspace: %q because autoplan is disabled", projCtx.RepoRelDir, projCtx.Workspace)
			continue
		}
		autoplanEnabled = append(autoplanEnabled, projCtx)
	}
	return autoplanEnabled, nil
}

// See ProjectCommandBuilder.BuildPlanCommands.
func (p *DefaultProjectCommandBuilder) BuildPlanCommands(ctx *command.Context, cmd *CommentCommand) ([]command.ProjectContext, error) {
	if !cmd.IsForSpecificProject() {
		return p.buildAllCommandsByCfg(ctx, cmd.CommandName(), cmd.Flags, cmd.Verbose)
	}
	pcc, err := p.buildProjectPlanCommand(ctx, cmd)
	return pcc, err
}

// See ProjectCommandBuilder.BuildApplyCommands.
func (p *DefaultProjectCommandBuilder) BuildApplyCommands(ctx *command.Context, cmd *CommentCommand) ([]command.ProjectContext, error) {
	if !cmd.IsForSpecificProject() {
		return p.buildAllProjectCommandsByPlan(ctx, cmd)
	}
	pac, err := p.buildProjectApplyCommand(ctx, cmd)
	return pac, err
}

func (p *DefaultProjectCommandBuilder) BuildApprovePoliciesCommands(ctx *command.Context, cmd *CommentCommand) ([]command.ProjectContext, error) {
	return p.buildAllProjectCommandsByPlan(ctx, cmd)
}

func (p *DefaultProjectCommandBuilder) BuildVersionCommands(ctx *command.Context, cmd *CommentCommand) ([]command.ProjectContext, error) {
	if !cmd.IsForSpecificProject() {
		return p.buildAllProjectCommandsByPlan(ctx, cmd)
	}
	pac, err := p.buildProjectVersionCommand(ctx, cmd)
	return pac, err
}

func (p *DefaultProjectCommandBuilder) BuildImportCommands(ctx *command.Context, cmd *CommentCommand) ([]command.ProjectContext, error) {
	if !cmd.IsForSpecificProject() {
		// import discard a plan file, so use buildAllCommandsByCfg instead buildAllProjectCommandsByPlan.
		return p.buildAllCommandsByCfg(ctx, cmd.CommandName(), cmd.Flags, cmd.Verbose)
	}
	return p.buildProjectImportCommand(ctx, cmd)
}

// buildAllCommandsByCfg builds init contexts for all projects we determine were
// modified in this ctx.
func (p *DefaultProjectCommandBuilder) buildAllCommandsByCfg(ctx *command.Context, cmdName command.Name, commentFlags []string, verbose bool) ([]command.ProjectContext, error) {
	// We'll need the list of modified files.
	modifiedFiles, err := p.VCSClient.GetModifiedFiles(ctx.Pull.BaseRepo, ctx.Pull)
	if err != nil {
		return nil, err
	}
	ctx.Log.Debug("%d files were modified in this pull request", len(modifiedFiles))

	if p.SkipCloneNoChanges && p.VCSClient.SupportsSingleFileDownload(ctx.Pull.BaseRepo) {
		repoCfgFile := p.GlobalCfg.RepoConfigFile(ctx.Pull.BaseRepo.ID())
		hasRepoCfg, repoCfgData, err := p.VCSClient.GetFileContent(ctx.Pull, repoCfgFile)
		if err != nil {
			return nil, errors.Wrapf(err, "downloading %s", repoCfgFile)
		}

		if hasRepoCfg {
			repoCfg, err := p.ParserValidator.ParseRepoCfgData(repoCfgData, p.GlobalCfg, ctx.Pull.BaseRepo.ID(), ctx.Pull.BaseBranch)
			if err != nil {
				return nil, errors.Wrapf(err, "parsing %s", repoCfgFile)
			}
			ctx.Log.Info("successfully parsed remote %s file", repoCfgFile)
			if len(repoCfg.Projects) > 0 {
				matchingProjects, err := p.ProjectFinder.DetermineProjectsViaConfig(ctx.Log, modifiedFiles, repoCfg, "")
				if err != nil {
					return nil, err
				}
				ctx.Log.Info("%d projects are changed on MR %q based on their when_modified config", len(matchingProjects), ctx.Pull.Num)
				if len(matchingProjects) == 0 {
					ctx.Log.Info("skipping repo clone since no project was modified")
					return []command.ProjectContext{}, nil
				}
			} else {
				ctx.Log.Info("No projects are defined in %s. Will resume automatic detection", repoCfgFile)
			}
			// NOTE: We discard this work here and end up doing it again after
			// cloning to ensure all the return values are set properly with
			// the actual clone directory.
		}
	}

	// Need to lock the workspace we're about to clone to.
	workspace := DefaultWorkspace

	unlockFn, err := p.WorkingDirLocker.TryLock(ctx.Pull.BaseRepo.FullName, ctx.Pull.Num, workspace, DefaultRepoRelDir)
	if err != nil {
		ctx.Log.Warn("workspace was locked")
		return nil, err
	}
	ctx.Log.Debug("got workspace lock")
	defer unlockFn()

	repoDir, _, err := p.WorkingDir.Clone(ctx.Log, ctx.HeadRepo, ctx.Pull, workspace)
	if err != nil {
		return nil, err
	}

	// Parse config file if it exists.
	repoCfgFile := p.GlobalCfg.RepoConfigFile(ctx.Pull.BaseRepo.ID())
	hasRepoCfg, err := p.ParserValidator.HasRepoCfg(repoDir, repoCfgFile)
	if err != nil {
		return nil, errors.Wrapf(err, "looking for %s file in %q", repoCfgFile, repoDir)
	}

	var projCtxs []command.ProjectContext
	var repoCfg valid.RepoCfg

	if hasRepoCfg {
		// If there's a repo cfg with projects then we'll use it to figure out which projects
		// should be planed.
		repoCfg, err = p.ParserValidator.ParseRepoCfg(repoDir, p.GlobalCfg, ctx.Pull.BaseRepo.ID(), ctx.Pull.BaseBranch)
		if err != nil {
			return nil, errors.Wrapf(err, "parsing %s", repoCfgFile)
		}
		ctx.Log.Info("successfully parsed %s file", repoCfgFile)
	}

	if len(repoCfg.Projects) > 0 {
		matchingProjects, err := p.ProjectFinder.DetermineProjectsViaConfig(ctx.Log, modifiedFiles, repoCfg, repoDir)
		if err != nil {
			return nil, err
		}
		ctx.Log.Info("%d projects are to be planned based on their when_modified config", len(matchingProjects))

		for _, mp := range matchingProjects {
			ctx.Log.Debug("determining config for project at dir: %q workspace: %q", mp.Dir, mp.Workspace)
			mergedCfg := p.GlobalCfg.MergeProjectCfg(ctx.Log, ctx.Pull.BaseRepo.ID(), mp, repoCfg)

			projCtxs = append(projCtxs,
				p.ProjectCommandContextBuilder.BuildProjectContext(
					ctx,
					cmdName,
					mergedCfg,
					commentFlags,
					repoDir,
					repoCfg.Automerge,
					repoCfg.ParallelApply,
					repoCfg.ParallelPlan,
					verbose,
					p.TerraformExecutor,
				)...)
		}
	} else {
		// If there is no config file or it specified no projects, then we'll plan each project that
		// our algorithm determines was modified.
		if hasRepoCfg {
			ctx.Log.Info("No projects are defined in %s. Will resume automatic detection", repoCfgFile)
		} else {
			ctx.Log.Info("found no %s file", repoCfgFile)
		}
		// build a module index for projects that are explicitly included
		moduleInfo, err := FindModuleProjects(repoDir, p.AutoDetectModuleFiles)
		if err != nil {
			ctx.Log.Warn("error(s) loading project module dependencies: %s", err)
		}
		ctx.Log.Debug("moduleInfo for %s (matching %q) = %v", repoDir, p.AutoDetectModuleFiles, moduleInfo)
		modifiedProjects := p.ProjectFinder.DetermineProjects(ctx.Log, modifiedFiles, ctx.Pull.BaseRepo.FullName, repoDir, p.AutoplanFileList, moduleInfo)
		ctx.Log.Info("automatically determined that there were %d projects modified in this pull request: %s", len(modifiedProjects), modifiedProjects)
		for _, mp := range modifiedProjects {
			ctx.Log.Debug("determining config for project at dir: %q", mp.Path)
			pWorkspace, err := p.ProjectFinder.DetermineWorkspaceFromHCL(ctx.Log, repoDir)
			if err != nil {
				return nil, errors.Wrapf(err, "looking for Terraform Cloud workspace from configuration %s", repoDir)
			}
			automerge := DefaultAutomergeEnabled
			parallelApply := DefaultParallelApplyEnabled
			parallelPlan := DefaultParallelPlanEnabled
			if hasRepoCfg {
				automerge = repoCfg.Automerge
				parallelApply = repoCfg.ParallelApply
				parallelPlan = repoCfg.ParallelPlan
			}
			pCfg := p.GlobalCfg.DefaultProjCfg(ctx.Log, ctx.Pull.BaseRepo.ID(), mp.Path, pWorkspace)

			projCtxs = append(projCtxs,
				p.ProjectCommandContextBuilder.BuildProjectContext(
					ctx,
					cmdName,
					pCfg,
					commentFlags,
					repoDir,
					automerge,
					parallelApply,
					parallelPlan,
					verbose,
					p.TerraformExecutor,
				)...)
		}
	}

	sort.Slice(projCtxs, func(i, j int) bool {
		return projCtxs[i].ExecutionOrderGroup < projCtxs[j].ExecutionOrderGroup
	})

	return projCtxs, nil
}

// buildProjectPlanCommand builds a plan context for a single project.
// cmd must be for only one project.
func (p *DefaultProjectCommandBuilder) buildProjectPlanCommand(ctx *command.Context, cmd *CommentCommand) ([]command.ProjectContext, error) {
	workspace := DefaultWorkspace
	if cmd.Workspace != "" {
		workspace = cmd.Workspace
	}

	var pcc []command.ProjectContext

	// use the default repository workspace because it is the only one guaranteed to have an atlantis.yaml,
	// other workspaces will not have the file if they are using pre_workflow_hooks to generate it dynamically
	defaultRepoDir, err := p.WorkingDir.GetWorkingDir(ctx.Pull.BaseRepo, ctx.Pull, DefaultWorkspace)
	if err != nil {
		return pcc, err
	}

	if p.RestrictFileList {
		modifiedFiles, err := p.VCSClient.GetModifiedFiles(ctx.Pull.BaseRepo, ctx.Pull)
		if err != nil {
			return nil, err
		}

		if cmd.RepoRelDir != "" {
			foundDir := false

			for _, f := range modifiedFiles {
				if filepath.Dir(f) == cmd.RepoRelDir {
					foundDir = true
				}
			}

			if !foundDir {
				return pcc, fmt.Errorf("the dir \"%s\" is not in the plan list of this pull request", cmd.RepoRelDir)
			}
		}

		if cmd.ProjectName != "" {
			var notFoundFiles = []string{}
			var repoConfig valid.RepoCfg

			repoConfig, err = p.ParserValidator.ParseRepoCfg(defaultRepoDir, p.GlobalCfg, ctx.Pull.BaseRepo.ID(), ctx.Pull.BaseBranch)
			if err != nil {
				return pcc, err
			}
			repoCfgProjects := repoConfig.FindProjectsByName(cmd.ProjectName)

			for _, f := range modifiedFiles {
				foundDir := false

				for _, p := range repoCfgProjects {
					if filepath.Dir(f) == p.Dir {
						foundDir = true
					}
				}

				if !foundDir {
					notFoundFiles = append(notFoundFiles, filepath.Dir(f))
				}
			}

			if len(notFoundFiles) > 0 {
				return pcc, fmt.Errorf("the following directories are present in the pull request but not in the requested project:\n%s", strings.Join(notFoundFiles, "\n"))
			}
		}
	}

	ctx.Log.Debug("building plan command")
	unlockFn, err := p.WorkingDirLocker.TryLock(ctx.Pull.BaseRepo.FullName, ctx.Pull.Num, workspace, DefaultRepoRelDir)
	if err != nil {
		return pcc, err
	}
	defer unlockFn()

	ctx.Log.Debug("cloning repository")
	_, _, err = p.WorkingDir.Clone(ctx.Log, ctx.HeadRepo, ctx.Pull, workspace)
	if err != nil {
		return pcc, err
	}

	repoRelDir := DefaultRepoRelDir
	if cmd.RepoRelDir != "" {
		repoRelDir = cmd.RepoRelDir
	}

	return p.buildProjectCommandCtx(
		ctx,
		command.Plan,
		cmd.ProjectName,
		cmd.Flags,
		defaultRepoDir,
		repoRelDir,
		workspace,
		cmd.Verbose,
	)
}

// getCfg returns the atlantis.yaml config (if it exists) for this project. If
// there is no config, then projectCfg and repoCfg will be nil.
func (p *DefaultProjectCommandBuilder) getCfg(ctx *command.Context, projectName string, dir string, workspace string, repoDir string) (projectsCfg []valid.Project, repoCfg *valid.RepoCfg, err error) {
	repoCfgFile := p.GlobalCfg.RepoConfigFile(ctx.Pull.BaseRepo.ID())
	hasRepoCfg, err := p.ParserValidator.HasRepoCfg(repoDir, repoCfgFile)
	if err != nil {
		err = errors.Wrapf(err, "looking for %s file in %q", repoCfgFile, repoDir)
		return
	}
	if !hasRepoCfg {
		if projectName != "" {
			err = fmt.Errorf("cannot specify a project name unless an %s file exists to configure projects", repoCfgFile)
			return
		}
		return
	}

	var repoConfig valid.RepoCfg
	repoConfig, err = p.ParserValidator.ParseRepoCfg(repoDir, p.GlobalCfg, ctx.Pull.BaseRepo.ID(), ctx.Pull.BaseBranch)
	if err != nil {
		return
	}
	repoCfg = &repoConfig

	// If they've specified a project by name we look it up. Otherwise we
	// use the dir and workspace.
	if projectName != "" {
		if p.EnableRegExpCmd {
			projectsCfg = repoCfg.FindProjectsByName(projectName)
		} else {
			if p := repoCfg.FindProjectByName(projectName); p != nil {
				projectsCfg = append(projectsCfg, *p)
			}
		}
		if len(projectsCfg) == 0 {
			err = fmt.Errorf("no project with name %q is defined in %s", projectName, repoCfgFile)
			return
		}
		return
	}

	projCfgs := repoCfg.FindProjectsByDirWorkspace(dir, workspace)
	if len(projCfgs) == 0 {
		return
	}
	if len(projCfgs) > 1 {
		err = fmt.Errorf("must specify project name: more than one project defined in %s matched dir: %q workspace: %q", repoCfgFile, dir, workspace)
		return
	}
	projectsCfg = projCfgs
	return
}

// buildAllProjectCommandsByPlan builds contexts for a command for every project that has
// pending plans in this ctx.
func (p *DefaultProjectCommandBuilder) buildAllProjectCommandsByPlan(ctx *command.Context, commentCmd *CommentCommand) ([]command.ProjectContext, error) {
	// Lock all dirs in this pull request (instead of a single dir) because we
	// don't know how many dirs we'll need to run the command in.
	unlockFn, err := p.WorkingDirLocker.TryLockPull(ctx.Pull.BaseRepo.FullName, ctx.Pull.Num)
	if err != nil {
		return nil, err
	}
	defer unlockFn()

	pullDir, err := p.WorkingDir.GetPullDir(ctx.Pull.BaseRepo, ctx.Pull)
	if err != nil {
		return nil, err
	}

	plans, err := p.PendingPlanFinder.Find(pullDir)
	if err != nil {
		return nil, err
	}

	// use the default repository workspace because it is the only one guaranteed to have an atlantis.yaml,
	// other workspaces will not have the file if they are using pre_workflow_hooks to generate it dynamically
	defaultRepoDir, err := p.WorkingDir.GetWorkingDir(ctx.Pull.BaseRepo, ctx.Pull, DefaultWorkspace)
	if err != nil {
		return nil, err
	}

	var cmds []command.ProjectContext
	for _, plan := range plans {
		commentCmds, err := p.buildProjectCommandCtx(ctx, commentCmd.CommandName(), plan.ProjectName, commentCmd.Flags, defaultRepoDir, plan.RepoRelDir, plan.Workspace, commentCmd.Verbose)
		if err != nil {
			return nil, errors.Wrapf(err, "building command for dir %q", plan.RepoRelDir)
		}
		cmds = append(cmds, commentCmds...)
	}

	sort.Slice(cmds, func(i, j int) bool {
		return cmds[i].ExecutionOrderGroup < cmds[j].ExecutionOrderGroup
	})

	return cmds, nil
}

// buildProjectApplyCommand builds an apply command for the single project
// identified by cmd.
func (p *DefaultProjectCommandBuilder) buildProjectApplyCommand(ctx *command.Context, cmd *CommentCommand) ([]command.ProjectContext, error) {
	workspace := DefaultWorkspace
	if cmd.Workspace != "" {
		workspace = cmd.Workspace
	}

	var projCtx []command.ProjectContext
	unlockFn, err := p.WorkingDirLocker.TryLock(ctx.Pull.BaseRepo.FullName, ctx.Pull.Num, workspace, DefaultRepoRelDir)
	if err != nil {
		return projCtx, err
	}
	defer unlockFn()

	// use the default repository workspace because it is the only one guaranteed to have an atlantis.yaml,
	// other workspaces will not have the file if they are using pre_workflow_hooks to generate it dynamically
	repoDir, err := p.WorkingDir.GetWorkingDir(ctx.Pull.BaseRepo, ctx.Pull, DefaultWorkspace)
	if os.IsNotExist(errors.Cause(err)) {
		return projCtx, errors.New("no working directory found–did you run plan?")
	} else if err != nil {
		return projCtx, err
	}

	repoRelDir := DefaultRepoRelDir
	if cmd.RepoRelDir != "" {
		repoRelDir = cmd.RepoRelDir
	}

	return p.buildProjectCommandCtx(
		ctx,
		command.Apply,
		cmd.ProjectName,
		cmd.Flags,
		repoDir,
		repoRelDir,
		workspace,
		cmd.Verbose,
	)
}

// buildProjectVersionCommand builds a version command for the single project
// identified by cmd.
func (p *DefaultProjectCommandBuilder) buildProjectVersionCommand(ctx *command.Context, cmd *CommentCommand) ([]command.ProjectContext, error) {
	workspace := DefaultWorkspace
	if cmd.Workspace != "" {
		workspace = cmd.Workspace
	}

	var projCtx []command.ProjectContext
	unlockFn, err := p.WorkingDirLocker.TryLock(ctx.Pull.BaseRepo.FullName, ctx.Pull.Num, workspace, DefaultRepoRelDir)
	if err != nil {
		return projCtx, err
	}
	defer unlockFn()

	// use the default repository workspace because it is the only one guaranteed to have an atlantis.yaml,
	// other workspaces will not have the file if they are using pre_workflow_hooks to generate it dynamically
	repoDir, err := p.WorkingDir.GetWorkingDir(ctx.Pull.BaseRepo, ctx.Pull, DefaultWorkspace)
	if os.IsNotExist(errors.Cause(err)) {
		return projCtx, errors.New("no working directory found–did you run plan?")
	} else if err != nil {
		return projCtx, err
	}

	repoRelDir := DefaultRepoRelDir
	if cmd.RepoRelDir != "" {
		repoRelDir = cmd.RepoRelDir
	}

	return p.buildProjectCommandCtx(
		ctx,
		command.Version,
		cmd.ProjectName,
		cmd.Flags,
		repoDir,
		repoRelDir,
		workspace,
		cmd.Verbose,
	)
}

// buildProjectImportCommand builds a import command for the single project
// identified by cmd.
func (p *DefaultProjectCommandBuilder) buildProjectImportCommand(ctx *command.Context, cmd *CommentCommand) ([]command.ProjectContext, error) {
	workspace := DefaultWorkspace
	if cmd.Workspace != "" {
		workspace = cmd.Workspace
	}

	var projCtx []command.ProjectContext
	unlockFn, err := p.WorkingDirLocker.TryLock(ctx.Pull.BaseRepo.FullName, ctx.Pull.Num, workspace, DefaultRepoRelDir)
	if err != nil {
		return projCtx, err
	}
	defer unlockFn()

	// use the default repository workspace because it is the only one guaranteed to have an atlantis.yaml,
	// other workspaces will not have the file if they are using pre_workflow_hooks to generate it dynamically
	repoDir, err := p.WorkingDir.GetWorkingDir(ctx.Pull.BaseRepo, ctx.Pull, DefaultWorkspace)
	if os.IsNotExist(errors.Cause(err)) {
		return projCtx, errors.New("no working directory found–did you run plan?")
	} else if err != nil {
		return projCtx, err
	}

	repoRelDir := DefaultRepoRelDir
	if cmd.RepoRelDir != "" {
		repoRelDir = cmd.RepoRelDir
	}

	return p.buildProjectCommandCtx(
		ctx,
		command.Import,
		cmd.ProjectName,
		cmd.Flags,
		repoDir,
		repoRelDir,
		workspace,
		cmd.Verbose,
	)
}

// buildProjectCommandCtx builds a context for a single or several projects identified
// by the parameters.
func (p *DefaultProjectCommandBuilder) buildProjectCommandCtx(ctx *command.Context,
	cmd command.Name,
	projectName string,
	commentFlags []string,
	repoDir string,
	repoRelDir string,
	workspace string,
	verbose bool) ([]command.ProjectContext, error) {

	matchingProjects, repoCfgPtr, err := p.getCfg(ctx, projectName, repoRelDir, workspace, repoDir)
	if err != nil {
		return []command.ProjectContext{}, err
	}
	var projCtxs []command.ProjectContext
	var projCfg valid.MergedProjectCfg
	automerge := DefaultAutomergeEnabled
	parallelApply := DefaultParallelApplyEnabled
	parallelPlan := DefaultParallelPlanEnabled
	if repoCfgPtr != nil {
		automerge = repoCfgPtr.Automerge
		parallelApply = repoCfgPtr.ParallelApply
		parallelPlan = repoCfgPtr.ParallelPlan
	}

	if len(matchingProjects) > 0 {
		// Override any dir/workspace defined on the comment with what was
		// defined in config. This shouldn't matter since we don't allow comments
		// with both project name and dir/workspace.
		repoRelDir = projCfg.RepoRelDir
		workspace = projCfg.Workspace
		for _, mp := range matchingProjects {
			ctx.Log.Debug("Merging config for project at dir: %q workspace: %q", mp.Dir, mp.Workspace)
			projCfg = p.GlobalCfg.MergeProjectCfg(ctx.Log, ctx.Pull.BaseRepo.ID(), mp, *repoCfgPtr)

			projCtxs = append(projCtxs,
				p.ProjectCommandContextBuilder.BuildProjectContext(
					ctx,
					cmd,
					projCfg,
					commentFlags,
					repoDir,
					automerge,
					parallelApply,
					parallelPlan,
					verbose,
					p.TerraformExecutor,
				)...)
		}
	} else {
		projCfg = p.GlobalCfg.DefaultProjCfg(ctx.Log, ctx.Pull.BaseRepo.ID(), repoRelDir, workspace)
		projCtxs = append(projCtxs,
			p.ProjectCommandContextBuilder.BuildProjectContext(
				ctx,
				cmd,
				projCfg,
				commentFlags,
				repoDir,
				automerge,
				parallelApply,
				parallelPlan,
				verbose,
				p.TerraformExecutor,
			)...)
	}

	if err := p.validateWorkspaceAllowed(repoCfgPtr, repoRelDir, workspace); err != nil {
		return []command.ProjectContext{}, err
	}

	return projCtxs, nil
}

// validateWorkspaceAllowed returns an error if repoCfg defines projects in
// repoRelDir but none of them use workspace. We want this to be an error
// because if users have gone to the trouble of defining projects in repoRelDir
// then it's likely that if we're running a command for a workspace that isn't
// defined then they probably just typed the workspace name wrong.
func (p *DefaultProjectCommandBuilder) validateWorkspaceAllowed(repoCfg *valid.RepoCfg, repoRelDir string, workspace string) error {
	if repoCfg == nil {
		return nil
	}

	return repoCfg.ValidateWorkspaceAllowed(repoRelDir, workspace)
}