package command

import (
	"fmt"
	"os"
	"strconv"

	"github.com/hashicorp/errwrap"
	"github.com/hashicorp/terraform/config"
	"github.com/hashicorp/terraform/config/module"
	"github.com/hashicorp/terraform/terraform"
)

// NOTE: Temporary file until this branch is cleaned up.

// Input returns whether or not input asking is enabled.
func (m *Meta) Input() bool {
	if test || !m.input {
		return false
	}

	if envVar := os.Getenv(InputModeEnvVar); envVar != "" {
		if v, err := strconv.ParseBool(envVar); err == nil && !v {
			return false
		}
	}

	return true
}

// Module loads the module tree for the given root path.
//
// It expects the modules to already be downloaded. This will never
// download any modules.
func (m *Meta) Module(path string) (*module.Tree, error) {
	mod, err := module.NewTreeModule("", path)
	if err != nil {
		// Check for the error where we have no config files
		if errwrap.ContainsType(err, new(config.ErrNoConfigsFound)) {
			return nil, nil
		}

		return nil, err
	}

	err = mod.Load(m.moduleStorage(m.DataDir()), module.GetModeNone)
	if err != nil {
		return nil, fmt.Errorf("Error loading modules: %s", err)
	}

	return mod, nil
}

// Plan returns the plan for the given path.
//
// This only has an effect if the path itself looks like a plan.
// If error is nil and the plan is nil, then the path didn't look like
// a plan.
//
// Error will be non-nil if path looks like a plan and loading the plan
// failed.
func (m *Meta) Plan(path string) (*terraform.Plan, error) {
	// Open the path no matter if its a directory or file
	f, err := os.Open(path)
	defer f.Close()
	if err != nil {
		return nil, fmt.Errorf(
			"Failed to load Terraform configuration or plan: %s", err)
	}

	// Stat it so we can check if its a directory
	fi, err := f.Stat()
	if err != nil {
		return nil, fmt.Errorf(
			"Failed to load Terraform configuration or plan: %s", err)
	}

	// If this path is a directory, then it can't be a plan. Not an error.
	if fi.IsDir() {
		return nil, nil
	}

	// Read the plan
	p, err := terraform.ReadPlan(f)
	if err != nil {
		return nil, err
	}

	// We do a validation here that seems odd but if any plan is given,
	// we must not have set any extra variables. The plan itself contains
	// the variables and those aren't overwritten.
	if len(m.variables) > 0 {
		return nil, fmt.Errorf(
			"You can't set variables with the '-var' or '-var-file' flag\n" +
				"when you're applying a plan file. The variables used when\n" +
				"the plan was created will be used. If you wish to use different\n" +
				"variable values, create a new plan file.")
	}

	return p, nil
}