package resource

import (
	"fmt"
	"log"

	"github.com/hashicorp/hcl2/hcl"
	"github.com/hashicorp/hcl2/hcl/hclsyntax"

	"github.com/hashicorp/terraform/addrs"
	"github.com/hashicorp/terraform/states"
	"github.com/hashicorp/terraform/terraform"
)

// testStepImportState runs an imort state test step
func testStepImportState(
	opts terraform.ContextOpts,
	state *terraform.State,
	step TestStep) (*terraform.State, error) {
	// Determine the ID to import
	var importId string
	switch {
	case step.ImportStateIdFunc != nil:
		var err error
		importId, err = step.ImportStateIdFunc(state)
		if err != nil {
			return state, err
		}
	case step.ImportStateId != "":
		importId = step.ImportStateId
	default:
		resource, err := testResource(step, state)
		if err != nil {
			return state, err
		}
		importId = resource.Primary.ID
	}

	importPrefix := step.ImportStateIdPrefix
	if importPrefix != "" {
		importId = fmt.Sprintf("%s%s", importPrefix, importId)
	}

	// Setup the context. We initialize with an empty state. We use the
	// full config for provider configurations.
	cfg, err := testConfig(opts, step)
	if err != nil {
		return state, err
	}

	opts.Config = cfg
	opts.State = states.NewState()
	ctx, stepDiags := terraform.NewContext(&opts)
	if stepDiags.HasErrors() {
		return state, stepDiags.Err()
	}

	// The test step provides the resource address as a string, so we need
	// to parse it to get an addrs.AbsResourceAddress to pass in to the
	// import method.
	traversal, hclDiags := hclsyntax.ParseTraversalAbs([]byte(step.ResourceName), "", hcl.Pos{})
	if hclDiags.HasErrors() {
		return nil, hclDiags
	}
	importAddr, stepDiags := addrs.ParseAbsResourceInstance(traversal)
	if stepDiags.HasErrors() {
		return nil, stepDiags.Err()
	}

	// Do the import
	newState, stepDiags := ctx.Import(&terraform.ImportOpts{
		// Set the module so that any provider config is loaded
		Config: cfg,

		Targets: []*terraform.ImportTarget{
			&terraform.ImportTarget{
				Addr: importAddr,
				ID:   importId,
			},
		},
	})
	if stepDiags.HasErrors() {
		log.Printf("[ERROR] Test: ImportState failure: %s", stepDiags.Err())
		return state, stepDiags.Err()
	}

	// Go through the new state and verify
	if step.ImportStateCheck != nil {
		var states []*states.ResourceInstanceObjectSrc
		for _, r := range newState.RootModule().Resources {
			for _, i := range r.Instances {
				if i.Current != nil {
					states = append(states, i.Current)
				}
			}
		}
		// TODO: update for new state types
		return nil, fmt.Errorf("ImportStateCheck call in testStepImportState not yet updated for new state types")
		/*if err := step.ImportStateCheck(states); err != nil {
			return state, err
		}*/
	}

	// Verify that all the states match
	if step.ImportStateVerify {
		return nil, fmt.Errorf("testStepImportStep ImportStateVerify not yet updated for new state types")
		/*
			new := newState.RootModule().Resources
			old := state.RootModule().Resources
			for _, r := range new {
				// Find the existing resource
				var oldR *terraform.ResourceState
				for _, r2 := range old {
					if r2.Primary != nil && r2.Primary.ID == r.Primary.ID && r2.Type == r.Type {
						oldR = r2
						break
					}
				}
				if oldR == nil {
					return state, fmt.Errorf(
						"Failed state verification, resource with ID %s not found",
						r.Primary.ID)
				}

				// Compare their attributes
				actual := make(map[string]string)
				for k, v := range r.Primary.Attributes {
					actual[k] = v
				}
				expected := make(map[string]string)
				for k, v := range oldR.Primary.Attributes {
					expected[k] = v
				}

				// Remove fields we're ignoring
				for _, v := range step.ImportStateVerifyIgnore {
					for k, _ := range actual {
						if strings.HasPrefix(k, v) {
							delete(actual, k)
						}
					}
					for k, _ := range expected {
						if strings.HasPrefix(k, v) {
							delete(expected, k)
						}
					}
				}

				if !reflect.DeepEqual(actual, expected) {
					// Determine only the different attributes
					for k, v := range expected {
						if av, ok := actual[k]; ok && v == av {
							delete(expected, k)
							delete(actual, k)
						}
					}

					spewConf := spew.NewDefaultConfig()
					spewConf.SortKeys = true
					return state, fmt.Errorf(
						"ImportStateVerify attributes not equivalent. Difference is shown below. Top is actual, bottom is expected."+
							"\n\n%s\n\n%s",
						spewConf.Sdump(actual), spewConf.Sdump(expected))
				}
			}
		*/
	}

	// Return the old state (non-imported) so we don't change anything.
	return state, nil
}