package main

import (
	"fmt"
	"gosh/cmd"
	"gosh/types"
	"gosh/utils"
	"os"
	"os/exec"
	"path/filepath"
	"strings"

	"github.com/chzyer/readline"
	"github.com/fatih/color"
)

func gosh_print_output(cmdo types.CmdOutput) {
	switch cmdo.Id {
	case 0:
		fmt.Printf(cmdo.Output)
	case 1:
		fmt.Printf("Error: %s\n", cmdo.Output)
	}
}

func parse_flags(parts []string) (map[string]string, []string) {
	flags := make(map[string]string)
	args := []string{}
	i := 0
	for i < len(parts) {
		if strings.HasPrefix(parts[i], "-") {
			key := parts[i]
			val := ""
			if i+1 < len(parts) && !strings.HasPrefix(parts[i+1], "-") {
				val = parts[i+1]
				i++
			}
			flags[key] = val
		} else {
			args = append(args, parts[i])
		}
		i++
	}
	return flags, args
}

func process_golshscript(sh *types.Shell, file_path string) {
	data, err := os.ReadFile(file_path)

	if err != nil {
		fmt.Println("Error: ", err)
		return
	}

	lines := strings.Split(string(data), "\n")

	for _, line := range lines {
		gosh_process_input(sh, strings.TrimSpace(line))
	}
}

func check_pathes(sh *types.Shell, name string, args []string) bool {
	var output types.CmdOutput

	program_found := false

	// Check Python Pathes
	for _, path := range sh.PyPaths {
		children, err := os.ReadDir(path)

		if err != nil {
			color.Red("Error reading path.")
			fmt.Println(err)
		}

		for _, child := range children {
			child_name := strings.TrimSpace(child.Name())
			if !child.IsDir() && child_name == name {
				program_found = true
				full_path := filepath.Join(path, child.Name())
				path_args := append([]string{full_path}, args...)
				comd := exec.Command("python3", path_args...)

				out, err := comd.Output()
				if err != nil {
					fmt.Print("Error: ")
					color.Red(err.Error())
				}

				output = types.CmdOutput{Id: 0, Output: string(out)}
			}
		}
	}

	if program_found {
		gosh_print_output(output)
	}

	return program_found
}

func gosh_process_input(sh *types.Shell, input string) {
	// Split by pipe and trim spaces
	commands := strings.Split(input, "|")
	var prevOutput types.CmdOutput

	for _, cmdStr := range commands {
		cmdStr = strings.TrimSpace(cmdStr)
		parts := strings.Fields(cmdStr)
		if len(parts) == 0 {
			continue
		}

		switch parts[0] {
		case "pwd":
			prevOutput = cmd.GoshPwd(sh)
		case "cd":
			if len(parts) < 2 {
				fmt.Println("Usage: cd <dir>")
				return
			}
			prevOutput = cmd.GoshCd(sh, parts[1])
		case "ls":
			if len(parts) > 1 {
				prevOutput = cmd.GoshLs(sh, parts[1:]...)
			} else {
				prevOutput = cmd.GoshLs(sh)
			}
		case "cat":
			if len(parts) < 2 {
				fmt.Println("Usage: cat <path to file>")
				return
			}
			prevOutput = cmd.GoshCat(sh, parts[1])
		case "grep":
			if len(parts) < 2 {
				fmt.Println("Usage: grep <pattern>")
				return
			}

			flags, args := parse_flags(parts)

			// Feed previous output to grep
			prevOutput = cmd.GoshGrep(sh, flags, prevOutput.Output, args[len(args)-1])
		case "clear":
			cmd.GoshClear()
		case "apath":
			if len(parts) < 2 {
				fmt.Println(("Usage: apath <path/dir>"))
				return
			}

			prevOutput = cmd.GolshPyapath(sh, parts[1])
		default:

			if !check_pathes(sh, parts[0], parts[1:]) {
				fmt.Println("Unknown command:", parts[0])
				return
			}
		}
	}

	gosh_print_output(prevOutput)
}

func main() {
	dir, _ := os.Getwd()

	// Init shell
	sh := types.Shell{
		Cd:      dir,
		PyPaths: []string{}}

	// Check for and execute .golshrc
	golshrc_path, _ := os.UserHomeDir()
	golshrc_path = golshrc_path + "/.golshrc"

	_, err := os.Stat(golshrc_path)

	golshrc_exists := err == nil
	if golshrc_exists {
		process_golshscript(&sh, golshrc_path)
	}

	// Set up readline
	rl, err := readline.NewEx(&readline.Config{
		Prompt:          sh.Cd + "> ",
		AutoComplete:    &utils.AutoCompleter{Sh: &sh},
		InterruptPrompt: "^C",
		EOFPrompt:       "exit",
	})

	if err != nil {
		panic(err)
	}

	defer rl.Close()

	cd_path_color := color.New(color.FgBlue)

	var should_exit = false
	for {
		rl.SetPrompt(cd_path_color.Sprint("GOLSH "+sh.Cd+"❯") + " ")

		input, err := rl.Readline()

		if err != nil {
			fmt.Println("Error reading input: ", err)
		}

		input = strings.TrimSpace(input)

		switch input {
		case "exit":
			should_exit = true
		default:
			gosh_process_input(&sh, input)
		}

		if should_exit {
			break
		}
	}
}