package modules

import (
	"bytes"
	_ "embed"
	"encoding/csv"
	"encoding/json"
	"fmt"
	"os"

	"github.com/spf13/cobra"
	"github.com/spf13/viper"
)

//go:embed resources/tests-struct.json
var testStructData []byte

var compatibilityCmd = &cobra.Command{
	Use:   "compatibility",
	Short: "Shows compatibility results",
	Long:  "Form compatibility table based on passed s3 tests",
	Example: `s3-tests-parser compatibility suite.csv
s3-tests-parser compatibility suite.json --format json`,
	RunE: runCompatibilityCmd,
}

type (
	TestsStructure struct {
		Groups []Group `json:"groups"`
	}

	Group struct {
		Name       string   `json:"name"`
		Tag        string   `json:"tag"`
		Skip       bool     `json:"skip"`
		SkipReason string   `json:"skip_reason"`
		Tests      []string `json:"tests"`
	}
)

var (
	Reset  = "\033[0m"
	Red    = "\033[31m"
	Green  = "\033[32m"
	Yellow = "\033[33m"
)

const (
	formatFlag = "format"
)

func initCompatibilityCmd() {
	compatibilityCmd.Flags().String(formatFlag, "csv", "format of input test suite file")
}

func runCompatibilityCmd(cmd *cobra.Command, args []string) error {
	if len(args) != 1 {
		return fmt.Errorf("expected exactly one arg, got: %v", args)
	}

	var testStruct TestsStructure
	if err := json.Unmarshal(testStructData, &testStruct); err != nil {
		return fmt.Errorf("failed to parse tests struct: %w", err)
	}

	testsMap, err := parseSuite(args[0], viper.GetString(formatFlag))
	if err != nil {
		return fmt.Errorf("parse tests: %w", err)
	}

	for _, group := range testStruct.Groups {
		if group.Skip {
			cmd.Println(fmt.Sprintf("%s; skip: %s", group.Name, group.SkipReason))
			continue
		}

		printResult(cmd, group, testsMap)
	}

	return nil
}

func printResult(cmd *cobra.Command, group Group, testsMap map[string]bool) {
	ln := float64(len(group.Tests))
	pass := 0.0

	for _, test := range group.Tests {
		if testsMap[test] {
			pass++
		}
	}

	color := Red
	rate := pass / ln
	if rate > 0.9 {
		color = Green
	} else if rate > 0.5 {
		color = Yellow
	}

	cmd.Println(fmt.Sprintf("%s%s: %d/%d \u001B[0m", color, group.Name, int(pass), int(ln)))
}

func parseSuite(filePath string, format string) (map[string]bool, error) {
	switch format {
	case "csv":
		return parseSuiteCSV(filePath)
	case "json":
		return parseSuiteJSON(filePath)
	default:
		return nil, fmt.Errorf("unknown format: %s", format)
	}
}

func parseSuiteCSV(filePath string) (map[string]bool, error) {
	data, err := os.ReadFile(filePath)
	if err != nil {
		return nil, fmt.Errorf("failed to read suite file: %w", err)
	}

	rr := csv.NewReader(bytes.NewReader(data))
	records, err := rr.ReadAll()
	if err != nil {
		return nil, fmt.Errorf("failed to parse suite file: %w", err)
	}

	indexName := -1
	indexStatus := -1
	tests := make(map[string]bool)

	for i, recs := range records {
		if i == 0 {
			for j, rec := range recs {
				if rec == "Name" {
					indexName = j
				} else if rec == "Status" {
					indexStatus = j
				}
			}

			if indexName == -1 || indexStatus == -1 {
				return nil, fmt.Errorf("invalid csv format, couldn't find 'Name' and 'Status' fields")
			}
		}

		tests[recs[indexName]] = recs[indexStatus] == "passed"
	}

	return tests, nil
}

type SuiteNode struct {
	Name     string      `json:"name"`
	Status   string      `json:"status"`
	Children []SuiteNode `json:"children"`
}

func parseSuiteJSON(filePath string) (map[string]bool, error) {
	data, err := os.ReadFile(filePath)
	if err != nil {
		return nil, fmt.Errorf("failed to read suite file: %w", err)
	}

	var suiteNode SuiteNode
	if err = json.Unmarshal(data, &suiteNode); err != nil {
		return nil, fmt.Errorf("failed to parse suite file: %w", err)
	}

	tests := make(map[string]bool)
	parseSuiteNode(suiteNode, tests)

	return tests, nil
}

func parseSuiteNode(node SuiteNode, res map[string]bool) {
	if node.Status != "" {
		res[node.Name] = node.Status == "passed"
		return
	}

	for _, child := range node.Children {
		parseSuiteNode(child, res)
	}
}