package gocmd

import (
	"fmt"
	"os"
	"os/exec"
	"path/filepath"
	"regexp"
	"strings"

	"github.com/charmbracelet/lipgloss"
	"github.com/leaanthony/clir"
)

func addGoTestCommand(parent *clir.Command) {
	var (
		coverage bool
		pkg      string
		run      string
		short    bool
		race     bool
		json     bool
		verbose  bool
	)

	testCmd := parent.NewSubCommand("test", "Run tests with coverage")
	testCmd.LongDescription("Run Go tests with coverage reporting.\n\n" +
		"Sets MACOSX_DEPLOYMENT_TARGET=26.0 to suppress linker warnings.\n" +
		"Filters noisy output and provides colour-coded coverage.\n\n" +
		"Examples:\n" +
		"  core go test\n" +
		"  core go test --coverage\n" +
		"  core go test --pkg ./pkg/crypt\n" +
		"  core go test --run TestHash")

	testCmd.BoolFlag("coverage", "Show detailed per-package coverage", &coverage)
	testCmd.StringFlag("pkg", "Package to test (default: ./...)", &pkg)
	testCmd.StringFlag("run", "Run only tests matching regexp", &run)
	testCmd.BoolFlag("short", "Run only short tests", &short)
	testCmd.BoolFlag("race", "Enable race detector", &race)
	testCmd.BoolFlag("json", "Output JSON results", &json)
	testCmd.BoolFlag("v", "Verbose output", &verbose)

	testCmd.Action(func() error {
		return runGoTest(coverage, pkg, run, short, race, json, verbose)
	})
}

func runGoTest(coverage bool, pkg, run string, short, race, jsonOut, verbose bool) error {
	if pkg == "" {
		pkg = "./..."
	}

	args := []string{"test"}

	if coverage {
		args = append(args, "-cover")
	} else {
		args = append(args, "-cover")
	}

	if run != "" {
		args = append(args, "-run", run)
	}
	if short {
		args = append(args, "-short")
	}
	if race {
		args = append(args, "-race")
	}
	if verbose {
		args = append(args, "-v")
	}

	args = append(args, pkg)

	if !jsonOut {
		fmt.Printf("%s Running tests\n", dimStyle.Render("Test:"))
		fmt.Printf("  %s %s\n", dimStyle.Render("Package:"), pkg)
		fmt.Println()
	}

	cmd := exec.Command("go", args...)
	cmd.Env = append(os.Environ(), "MACOSX_DEPLOYMENT_TARGET=26.0", "CGO_ENABLED=0")
	cmd.Dir, _ = os.Getwd()

	output, err := cmd.CombinedOutput()
	outputStr := string(output)

	// Filter linker warnings
	lines := strings.Split(outputStr, "\n")
	var filtered []string
	for _, line := range lines {
		if !strings.Contains(line, "ld: warning:") {
			filtered = append(filtered, line)
		}
	}
	outputStr = strings.Join(filtered, "\n")

	// Parse results
	passed, failed, skipped := parseTestResults(outputStr)
	cov := parseOverallCoverage(outputStr)

	if jsonOut {
		fmt.Printf(`{"passed":%d,"failed":%d,"skipped":%d,"coverage":%.1f,"exit_code":%d}`,
			passed, failed, skipped, cov, cmd.ProcessState.ExitCode())
		fmt.Println()
		return err
	}

	// Print filtered output if verbose or failed
	if verbose || err != nil {
		fmt.Println(outputStr)
	}

	// Summary
	if err == nil {
		fmt.Printf("  %s %d passed\n", successStyle.Render("✓"), passed)
	} else {
		fmt.Printf("  %s %d passed, %d failed\n", errorStyle.Render("✗"), passed, failed)
	}

	if cov > 0 {
		covStyle := successStyle
		if cov < 50 {
			covStyle = errorStyle
		} else if cov < 80 {
			covStyle = lipgloss.NewStyle().Foreground(lipgloss.Color("#f59e0b"))
		}
		fmt.Printf("\n  %s %s\n", dimStyle.Render("Coverage:"), covStyle.Render(fmt.Sprintf("%.1f%%", cov)))
	}

	if err == nil {
		fmt.Printf("\n%s\n", successStyle.Render("PASS All tests passed"))
	} else {
		fmt.Printf("\n%s\n", errorStyle.Render("FAIL Some tests failed"))
	}

	return err
}

func parseTestResults(output string) (passed, failed, skipped int) {
	passRe := regexp.MustCompile(`(?m)^ok\s+`)
	failRe := regexp.MustCompile(`(?m)^FAIL\s+`)
	skipRe := regexp.MustCompile(`(?m)^\?\s+`)

	passed = len(passRe.FindAllString(output, -1))
	failed = len(failRe.FindAllString(output, -1))
	skipped = len(skipRe.FindAllString(output, -1))
	return
}

func parseOverallCoverage(output string) float64 {
	re := regexp.MustCompile(`coverage:\s+([\d.]+)%`)
	matches := re.FindAllStringSubmatch(output, -1)
	if len(matches) == 0 {
		return 0
	}

	var total float64
	for _, m := range matches {
		var cov float64
		fmt.Sscanf(m[1], "%f", &cov)
		total += cov
	}
	return total / float64(len(matches))
}

func addGoCovCommand(parent *clir.Command) {
	var (
		pkg       string
		html      bool
		open      bool
		threshold float64
	)

	covCmd := parent.NewSubCommand("cov", "Run tests with coverage report")
	covCmd.LongDescription("Run tests and generate coverage report.\n\n" +
		"Examples:\n" +
		"  core go cov                  # Run with coverage summary\n" +
		"  core go cov --html           # Generate HTML report\n" +
		"  core go cov --open           # Generate and open HTML report\n" +
		"  core go cov --threshold 80   # Fail if coverage < 80%")

	covCmd.StringFlag("pkg", "Package to test (default: ./...)", &pkg)
	covCmd.BoolFlag("html", "Generate HTML coverage report", &html)
	covCmd.BoolFlag("open", "Generate and open HTML report in browser", &open)
	covCmd.Float64Flag("threshold", "Minimum coverage percentage (exit 1 if below)", &threshold)

	covCmd.Action(func() error {
		if pkg == "" {
			// Auto-discover packages with tests
			pkgs, err := findTestPackages(".")
			if err != nil {
				return fmt.Errorf("failed to discover test packages: %w", err)
			}
			if len(pkgs) == 0 {
				return fmt.Errorf("no test packages found")
			}
			pkg = strings.Join(pkgs, " ")
		}

		// Create temp file for coverage data
		covFile, err := os.CreateTemp("", "coverage-*.out")
		if err != nil {
			return fmt.Errorf("failed to create coverage file: %w", err)
		}
		covPath := covFile.Name()
		covFile.Close()
		defer os.Remove(covPath)

		fmt.Printf("%s Running tests with coverage\n", dimStyle.Render("Coverage:"))
		// Truncate package list if too long for display
		displayPkg := pkg
		if len(displayPkg) > 60 {
			displayPkg = displayPkg[:57] + "..."
		}
		fmt.Printf("  %s %s\n", dimStyle.Render("Package:"), displayPkg)
		fmt.Println()

		// Run tests with coverage
		// We need to split pkg into individual arguments if it contains spaces
		pkgArgs := strings.Fields(pkg)
		args := append([]string{"test", "-coverprofile=" + covPath, "-covermode=atomic"}, pkgArgs...)

		cmd := exec.Command("go", args...)
		cmd.Env = append(os.Environ(), "MACOSX_DEPLOYMENT_TARGET=26.0")
		cmd.Stdout = os.Stdout
		cmd.Stderr = os.Stderr

		testErr := cmd.Run()

		// Get coverage percentage
		covCmd := exec.Command("go", "tool", "cover", "-func="+covPath)
		covOutput, err := covCmd.Output()
		if err != nil {
			if testErr != nil {
				return testErr
			}
			return fmt.Errorf("failed to get coverage: %w", err)
		}

		// Parse total coverage from last line
		lines := strings.Split(strings.TrimSpace(string(covOutput)), "\n")
		var totalCov float64
		if len(lines) > 0 {
			lastLine := lines[len(lines)-1]
			// Format: "total:    (statements)    XX.X%"
			if strings.Contains(lastLine, "total:") {
				parts := strings.Fields(lastLine)
				if len(parts) >= 3 {
					covStr := strings.TrimSuffix(parts[len(parts)-1], "%")
					fmt.Sscanf(covStr, "%f", &totalCov)
				}
			}
		}

		// Print coverage summary
		fmt.Println()
		covStyle := successStyle
		if totalCov < 50 {
			covStyle = errorStyle
		} else if totalCov < 80 {
			covStyle = lipgloss.NewStyle().Foreground(lipgloss.Color("#f59e0b"))
		}
		fmt.Printf("  %s %s\n", dimStyle.Render("Total:"), covStyle.Render(fmt.Sprintf("%.1f%%", totalCov)))

		// Generate HTML if requested
		if html || open {
			htmlPath := "coverage.html"
			htmlCmd := exec.Command("go", "tool", "cover", "-html="+covPath, "-o="+htmlPath)
			if err := htmlCmd.Run(); err != nil {
				return fmt.Errorf("failed to generate HTML: %w", err)
			}
			fmt.Printf("  %s %s\n", dimStyle.Render("HTML:"), htmlPath)

			if open {
				// Open in browser
				var openCmd *exec.Cmd
				switch {
				case exec.Command("which", "open").Run() == nil:
					openCmd = exec.Command("open", htmlPath)
				case exec.Command("which", "xdg-open").Run() == nil:
					openCmd = exec.Command("xdg-open", htmlPath)
				default:
					fmt.Printf("  %s\n", dimStyle.Render("(open manually)"))
				}
				if openCmd != nil {
					openCmd.Run()
				}
			}
		}

		// Check threshold
		if threshold > 0 && totalCov < threshold {
			fmt.Printf("\n%s Coverage %.1f%% is below threshold %.1f%%\n",
				errorStyle.Render("FAIL"), totalCov, threshold)
			return fmt.Errorf("coverage below threshold")
		}

		if testErr != nil {
			return testErr
		}

		fmt.Printf("\n%s\n", successStyle.Render("OK"))
		return nil
	})
}

func findTestPackages(root string) ([]string, error) {
	pkgMap := make(map[string]bool)
	err := filepath.Walk(root, func(path string, info os.FileInfo, err error) error {
		if err != nil {
			return nil
		}
		if !info.IsDir() && strings.HasSuffix(info.Name(), "_test.go") {
			dir := filepath.Dir(path)
			if !strings.HasPrefix(dir, ".") {
				dir = "./" + dir
			}
			pkgMap[dir] = true
		}
		return nil
	})
	if err != nil {
		return nil, err
	}

	var pkgs []string
	for pkg := range pkgMap {
		pkgs = append(pkgs, pkg)
	}
	return pkgs, nil
}