package main

import (
	"os"
	"path/filepath"
	"strconv"
	"strings"
)

// FindClaudeProcesses scans procDir (typically "/proc") for active Claude Code processes.
// It returns a Process for each PID whose cmdline starts with "claude".
// Read errors (permission denied, vanished process) are silently skipped.
func FindClaudeProcesses(procDir string) ([]Process, error) {
	entries, err := os.ReadDir(procDir)
	if err != nil {
		return nil, err
	}

	var procs []Process

	for _, entry := range entries {
		pid, err := strconv.Atoi(entry.Name())
		if err != nil {
			continue // not a PID directory
		}

		cmdlineData, err := os.ReadFile(filepath.Join(procDir, entry.Name(), "cmdline"))
		if err != nil {
			continue // permission denied or process vanished
		}

		parts := strings.Split(strings.TrimRight(string(cmdlineData), "\x00"), "\x00")
		if len(parts) == 0 {
			continue
		}

		// Match if the binary name ends with "claude" or is exactly "claude"
		bin := filepath.Base(parts[0])
		if bin != "claude" {
			continue
		}

		cwd, err := os.Readlink(filepath.Join(procDir, entry.Name(), "cwd"))
		if err != nil {
			continue // cannot read cwd
		}

		procs = append(procs, Process{
			PID: pid,
			Cmd: parts,
			Cwd: cwd,
		})
	}

	return procs, nil
}

// EncodePath converts an absolute path to the folder name format used by
// ~/.claude/projects/. Slashes and dots are replaced with dashes.
func EncodePath(path string) string {
	return strings.NewReplacer("/", "-", ".", "-").Replace(path)
}