package codeql

import (
	"archive/zip"
	"bytes"
	"encoding/json"
	"fmt"
	"io"
	"log"
	"log/slog"
	"mrvacommander/utils"
	"os"
	"os/exec"
	"path/filepath"

	"gopkg.in/yaml.v3"
)

func contains(slice []string, item string) bool {
	for _, s := range slice {
		if s == item {
			return true
		}
	}
	return false
}

func getCodeQLCLIPath() (string, error) {
	// get the CODEQL_CLI_PATH environment variable
	codeqlCliPath := os.Getenv("CODEQL_CLI_PATH")
	if codeqlCliPath == "" {
		return "", fmt.Errorf("CODEQL_CLI_PATH environment variable not set")
	}
	return codeqlCliPath, nil
}

func GenerateResultsZipArchive(runQueryResult *RunQueryResult) ([]byte, error) {
	buffer := new(bytes.Buffer)
	zipWriter := zip.NewWriter(buffer)

	if runQueryResult.SarifFilePath != "" {
		err := addFileToZip(zipWriter, runQueryResult.SarifFilePath, "results.sarif")
		if err != nil {
			return nil, fmt.Errorf("failed to add SARIF file to zip: %v", err)
		}
	}

	for _, relativePath := range runQueryResult.BqrsFilePaths.RelativeFilePaths {
		fullPath := filepath.Join(runQueryResult.BqrsFilePaths.BasePath, relativePath)
		err := addFileToZip(zipWriter, fullPath, relativePath)
		if err != nil {
			return nil, fmt.Errorf("failed to add BQRS file to zip: %v", err)
		}
	}

	err := zipWriter.Close()
	if err != nil {
		return nil, fmt.Errorf("failed to close zip writer: %v", err)
	}

	return buffer.Bytes(), nil
}

func addFileToZip(zipWriter *zip.Writer, filePath, zipPath string) error {
	file, err := os.Open(filePath)
	if err != nil {
		return fmt.Errorf("failed to open file %s: %v", filePath, err)
	}
	defer file.Close()

	w, err := zipWriter.Create(zipPath)
	if err != nil {
		return fmt.Errorf("failed to create zip entry for %s: %v", zipPath, err)
	}

	_, err = io.Copy(w, file)
	if err != nil {
		return fmt.Errorf("failed to copy file content to zip entry for %s: %v", zipPath, err)
	}

	return nil
}

func RunQuery(database string, nwo string, queryPackPath string, tempDir string) (*RunQueryResult, error) {
	path, err := getCodeQLCLIPath()

	if err != nil {
		return nil, fmt.Errorf("failed to get codeql cli path: %v", err)
	}

	codeql := CodeqlCli{path}

	resultsDir := filepath.Join(tempDir, "results")
	if err = os.Mkdir(resultsDir, 0755); err != nil {
		return nil, fmt.Errorf("failed to create results directory: %v", err)
	}

	databasePath := filepath.Join(tempDir, "db")
	if utils.UnzipFile(database, databasePath) != nil {
		return nil, fmt.Errorf("failed to unzip database: %v", err)
	}

	dbMetadata, err := getDatabaseMetadata(databasePath)
	if err != nil {
		return nil, fmt.Errorf("failed to get database metadata: %v", err)
	}

	// Check if the database has CreationMetadata / a SHA
	var databaseSHA string
	if dbMetadata.CreationMetadata == nil || dbMetadata.CreationMetadata.SHA == nil {
		// If the database does not have a SHA, we can proceed regardless
		slog.Warn("Database does not have a SHA")
		databaseSHA = ""
	} else {
		databaseSHA = *dbMetadata.CreationMetadata.SHA
	}

	cmd := exec.Command(codeql.Path, "database", "run-queries", "--ram=2048", "--additional-packs", queryPackPath, "--", databasePath, queryPackPath)
	if output, err := cmd.CombinedOutput(); err != nil {
		return nil, fmt.Errorf("failed to run queries: %v\nOutput: %s", err, output)
	}

	queryPackRunResults, err := getQueryPackRunResults(codeql, databasePath, queryPackPath)
	if err != nil {
		return nil, fmt.Errorf("failed to get query pack run results: %v", err)
	}

	sourceLocationPrefix, err := getSourceLocationPrefix(codeql, databasePath)
	if err != nil {
		return nil, fmt.Errorf("failed to get source location prefix: %v", err)
	}

	shouldGenerateSarif := queryPackSupportsSarif(queryPackRunResults)

	if shouldGenerateSarif {
		slog.Debug("Query pack supports SARIF")
	} else {
		slog.Debug("Query pack does not support SARIF")
	}

	var resultCount int
	var sarifFilePath string

	if shouldGenerateSarif {
		sarif, err := generateSarif(codeql, nwo, databasePath, queryPackPath, databaseSHA, resultsDir)
		if err != nil {
			return nil, fmt.Errorf("failed to generate SARIF: %v", err)
		}
		resultCount = getSarifResultCount(sarif)
		slog.Debug("Generated SARIF", "resultCount", resultCount)
		sarifFilePath = filepath.Join(resultsDir, "results.sarif")
		if err := os.WriteFile(sarifFilePath, sarif, 0644); err != nil {
			return nil, fmt.Errorf("failed to write SARIF file: %v", err)
		}
	} else {
		resultCount = queryPackRunResults.TotalResultsCount
		slog.Debug("Did not generate SARIF", "resultCount", resultCount)
	}

	slog.Debug("Adjusting BQRS files")
	bqrsFilePaths, err := adjustBqrsFiles(queryPackRunResults, resultsDir)
	if err != nil {
		return nil, fmt.Errorf("failed to adjust BQRS files: %v", err)
	}

	return &RunQueryResult{
		ResultCount:          resultCount,
		DatabaseSHA:          databaseSHA,
		SourceLocationPrefix: sourceLocationPrefix,
		BqrsFilePaths:        bqrsFilePaths,
		SarifFilePath:        sarifFilePath,
	}, nil
}

func getDatabaseMetadata(databasePath string) (*DatabaseMetadata, error) {
	data, err := os.ReadFile(filepath.Join(databasePath, "codeql-database.yml"))
	if err != nil {
		return nil, fmt.Errorf("failed to read database metadata: %v", err)
	}

	var metadata DatabaseMetadata
	if err := yaml.Unmarshal(data, &metadata); err != nil {
		return nil, fmt.Errorf("failed to unmarshal database metadata: %v", err)
	}

	return &metadata, nil
}

func runCommand(command []string) (CodeQLCommandOutput, error) {
	slog.Info("Running command", "command", command)
	cmd := exec.Command(command[0], command[1:]...)
	stdout, err := cmd.Output()
	if err != nil {
		return CodeQLCommandOutput{ExitCode: 1}, err
	}
	return CodeQLCommandOutput{ExitCode: 0, Stdout: string(stdout)}, nil
}

func validateQueryMetadataObject(data []byte) (QueryMetadata, error) {
	var queryMetadata QueryMetadata
	if err := json.Unmarshal(data, &queryMetadata); err != nil {
		return QueryMetadata{}, err
	}
	return queryMetadata, nil
}

func validateBQRSInfoObject(data []byte) (BQRSInfo, error) {
	var bqrsInfo BQRSInfo
	if err := json.Unmarshal(data, &bqrsInfo); err != nil {
		return BQRSInfo{}, err
	}
	return bqrsInfo, nil
}

func getBqrsInfo(codeql CodeqlCli, bqrs string) (BQRSInfo, error) {
	bqrsInfoOutput, err := runCommand([]string{codeql.Path, "bqrs", "info", "--format=json", bqrs})
	if err != nil {
		return BQRSInfo{}, fmt.Errorf("unable to run codeql bqrs info. Error: %v", err)
	}
	if bqrsInfoOutput.ExitCode != 0 {
		return BQRSInfo{}, fmt.Errorf("unable to run codeql bqrs info. Exit code: %d", bqrsInfoOutput.ExitCode)
	}
	return validateBQRSInfoObject([]byte(bqrsInfoOutput.Stdout))
}

func getQueryMetadata(codeql CodeqlCli, query string) (QueryMetadata, error) {
	queryMetadataOutput, err := runCommand([]string{codeql.Path, "resolve", "metadata", "--format=json", query})
	if err != nil {
		return QueryMetadata{}, fmt.Errorf("unable to run codeql resolve metadata. Error: %v", err)
	}
	if queryMetadataOutput.ExitCode != 0 {
		return QueryMetadata{}, fmt.Errorf("unable to run codeql resolve metadata. Exit code: %d", queryMetadataOutput.ExitCode)
	}
	return validateQueryMetadataObject([]byte(queryMetadataOutput.Stdout))
}

func getQueryPackRunResults(codeql CodeqlCli, databasePath, queryPackPath string) (*QueryPackRunResults, error) {
	resultsBasePath := filepath.Join(databasePath, "results")

	queryPaths := []string{} // Replace with actual query paths resolution logic

	var queries []Query
	for _, queryPath := range queryPaths {
		relativeBqrsFilePath := filepath.Join(queryPackPath, queryPath)
		bqrsFilePath := filepath.Join(resultsBasePath, relativeBqrsFilePath)

		if _, err := os.Stat(bqrsFilePath); os.IsNotExist(err) {
			return nil, fmt.Errorf("could not find BQRS file for query %s at %s", queryPath, bqrsFilePath)
		}

		bqrsInfo, err := getBqrsInfo(codeql, bqrsFilePath)
		if err != nil {
			return nil, fmt.Errorf("failed to get BQRS info: %v", err)
		}

		queryMetadata, err := getQueryMetadata(codeql, queryPath)
		if err != nil {
			return nil, fmt.Errorf("failed to get query metadata: %v", err)
		}

		queries = append(queries, Query{
			QueryPath:            queryPath,
			QueryMetadata:        queryMetadata,
			RelativeBqrsFilePath: relativeBqrsFilePath,
			BqrsInfo:             bqrsInfo,
		})
	}

	totalResultsCount := 0
	for _, query := range queries {
		count, err := getBqrsResultCount(query.BqrsInfo)
		if err != nil {
			return nil, fmt.Errorf("failed to get BQRS result count: %v", err)
		}
		totalResultsCount += count
	}

	return &QueryPackRunResults{
		Queries:           queries,
		TotalResultsCount: totalResultsCount,
		ResultsBasePath:   resultsBasePath,
	}, nil
}

func adjustBqrsFiles(queryPackRunResults *QueryPackRunResults, resultsDir string) (BqrsFilePaths, error) {
	if len(queryPackRunResults.Queries) == 1 {
		currentBqrsFilePath := filepath.Join(queryPackRunResults.ResultsBasePath, queryPackRunResults.Queries[0].RelativeBqrsFilePath)
		newBqrsFilePath := filepath.Join(resultsDir, "results.bqrs")

		if err := os.MkdirAll(resultsDir, os.ModePerm); err != nil {
			return BqrsFilePaths{}, err
		}

		if err := os.Rename(currentBqrsFilePath, newBqrsFilePath); err != nil {
			return BqrsFilePaths{}, err
		}

		return BqrsFilePaths{BasePath: resultsDir, RelativeFilePaths: []string{"results.bqrs"}}, nil
	}

	relativeFilePaths := make([]string, len(queryPackRunResults.Queries))
	for i, query := range queryPackRunResults.Queries {
		relativeFilePaths[i] = query.RelativeBqrsFilePath
	}

	return BqrsFilePaths{
		BasePath:          queryPackRunResults.ResultsBasePath,
		RelativeFilePaths: relativeFilePaths,
	}, nil
}

func getSourceLocationPrefix(codeql CodeqlCli, databasePath string) (string, error) {
	cmd := exec.Command(codeql.Path, "resolve", "database", databasePath)
	output, err := cmd.CombinedOutput()
	if err != nil {
		return "", fmt.Errorf("failed to resolve database: %v\nOutput: %s", err, output)
	}

	var resolvedDatabase ResolvedDatabase
	if err := json.Unmarshal(output, &resolvedDatabase); err != nil {
		return "", fmt.Errorf("failed to unmarshal resolved database: %v", err)
	}

	return resolvedDatabase.SourceLocationPrefix, nil
}

func queryPackSupportsSarif(queryPackRunResults *QueryPackRunResults) bool {
	for _, query := range queryPackRunResults.Queries {
		if !querySupportsSarif(query.QueryMetadata, query.BqrsInfo) {
			return false
		}
	}
	return true
}

func querySupportsSarif(queryMetadata QueryMetadata, bqrsInfo BQRSInfo) bool {
	return getSarifOutputType(queryMetadata, bqrsInfo.CompatibleQueryKinds) != ""
}

func getSarifOutputType(queryMetadata QueryMetadata, compatibleQueryKinds []string) string {
	if (*queryMetadata.Kind == "path-problem" || *queryMetadata.Kind == "path-alert") && contains(compatibleQueryKinds, "PathProblem") {
		return "path-problem"
	}
	if (*queryMetadata.Kind == "problem" || *queryMetadata.Kind == "alert") && contains(compatibleQueryKinds, "Problem") {
		return "problem"
	}
	return ""
}

func generateSarif(codeql CodeqlCli, nwo, databasePath, queryPackPath, databaseSHA string, resultsDir string) ([]byte, error) {
	sarifFile := filepath.Join(resultsDir, "results.sarif")
	cmd := exec.Command(codeql.Path, "database", "interpret-results", "--format=sarif-latest", "--output="+sarifFile, "--sarif-add-snippets", "--no-group-results", databasePath, queryPackPath)
	if output, err := cmd.CombinedOutput(); err != nil {
		return nil, fmt.Errorf("failed to generate SARIF: %v\nOutput: %s", err, output)
	}

	sarifData, err := os.ReadFile(sarifFile)
	if err != nil {
		return nil, fmt.Errorf("failed to read SARIF file: %v", err)
	}

	var sarif Sarif
	if err := json.Unmarshal(sarifData, &sarif); err != nil {
		return nil, fmt.Errorf("failed to unmarshal SARIF: %v", err)
	}

	injectVersionControlInfo(&sarif, nwo, databaseSHA)
	sarifBytes, err := json.Marshal(sarif)
	if err != nil {
		return nil, fmt.Errorf("failed to marshal SARIF: %v", err)
	}

	return sarifBytes, nil
}

func injectVersionControlInfo(sarif *Sarif, nwo, databaseSHA string) {
	for _, run := range sarif.Runs {
		run.VersionControlProvenance = append(run.VersionControlProvenance, map[string]interface{}{
			"repositoryUri": fmt.Sprintf("%s/%s", os.Getenv("GITHUB_SERVER_URL"), nwo),
			"revisionId":    databaseSHA,
		})
	}
}

// getSarifResultCount returns the number of results in the SARIF file.
func getSarifResultCount(sarif []byte) int {
	var sarifData Sarif
	if err := json.Unmarshal(sarif, &sarifData); err != nil {
		log.Printf("failed to unmarshal SARIF for result count: %v", err)
		return 0
	}
	count := 0
	for _, run := range sarifData.Runs {
		count += len(run.Results)
	}
	return count
}

// Known result set names
var KnownResultSetNames = []string{"#select", "problems"}

// getBqrssResultCount returns the number of results in the BQRS file.
func getBqrsResultCount(bqrsInfo BQRSInfo) (int, error) {
	for _, name := range KnownResultSetNames {
		for _, resultSet := range bqrsInfo.ResultSets {
			if resultSet.Name == name {
				return resultSet.Rows, nil
			}
		}
	}
	var resultSetNames []string
	for _, resultSet := range bqrsInfo.ResultSets {
		resultSetNames = append(resultSetNames, resultSet.Name)
	}
	return 0, fmt.Errorf(
		"BQRS does not contain any result sets matching known names. Expected one of %s but found %s",
		KnownResultSetNames, resultSetNames,
	)
}