package graph

import (
	"context"
	"errors"

	"github.com/gruntwork-io/terragrunt/internal/runner"
	"github.com/gruntwork-io/terragrunt/internal/runner/common"

	"github.com/gruntwork-io/terragrunt/cli/commands/common/runall"
	"github.com/gruntwork-io/terragrunt/config"
	"github.com/gruntwork-io/terragrunt/internal/os/stdout"
	"github.com/gruntwork-io/terragrunt/internal/report"
	"github.com/gruntwork-io/terragrunt/pkg/log"

	"github.com/gruntwork-io/terragrunt/options"
	"github.com/gruntwork-io/terragrunt/shell"
)

func Run(ctx context.Context, l log.Logger, opts *options.TerragruntOptions) error {
	cfg, err := config.ReadTerragruntConfig(ctx, l, opts, config.DefaultParserOptions(l, opts))
	if err != nil {
		return err
	}

	if cfg == nil {
		return errors.New("terragrunt was not able to render the config as json because it received no config. This is almost certainly a bug in Terragrunt. Please open an issue on github.com/gruntwork-io/terragrunt with this message and the contents of your terragrunt.hcl")
	}
	// consider root for graph identification passed destroy-graph-root argument
	rootDir := opts.GraphRoot

	// if destroy-graph-root is empty, use git to find top level dir.
	// may cause issues if in the same repo exist unrelated modules which will generate errors when scanning.
	if rootDir == "" {
		gitRoot, err := shell.GitTopLevelDir(ctx, l, opts, opts.WorkingDir)
		if err != nil {
			return err
		}

		rootDir = gitRoot
	}

	// Clone options and set RootWorkingDir to rootDir so discovery starts from the graph root
	// This allows discovering all modules including dependents (modules that depend on the working dir)
	graphOpts := opts.Clone()
	graphOpts.RootWorkingDir = rootDir

	stackOpts := []common.Option{}

	r := report.NewReport().WithWorkingDir(opts.WorkingDir)

	if l.Formatter().DisabledColors() || stdout.IsRedirected() {
		r.WithDisableColor()
	}

	if opts.ReportFormat != "" {
		r.WithFormat(opts.ReportFormat)
	}

	if opts.SummaryPerUnit {
		r.WithShowUnitLevelSummary()
	}

	// Create graph dependency filter to show only the working directory and its dependents
	graphFilter := &common.UnitFilterGraph{
		TargetDir: opts.WorkingDir,
	}

	// Add unit filter for graph command to filter units based on dependencies
	// This will be applied after units are resolved but before the queue is built
	stackOpts = append(stackOpts, common.WithReport(r), common.WithUnitFilters(graphFilter))

	if opts.ReportSchemaFile != "" {
		defer r.WriteSchemaToFile(opts.ReportSchemaFile) //nolint:errcheck
	}

	if opts.ReportFile != "" {
		defer r.WriteToFile(opts.ReportFile) //nolint:errcheck
	}

	if !opts.SummaryDisable {
		defer r.WriteSummary(opts.Writer) //nolint:errcheck
	}

	stack, err := runner.FindStackInSubfolders(ctx, l, graphOpts, stackOpts...)
	if err != nil {
		return err
	}

	return runall.RunAllOnStack(ctx, l, graphOpts, stack)
}
