package main

import (
	"encoding/json"
	"fmt"
	"io"
	"log"
	"os"
	"os/exec"
	"strconv"
	"strings"

	"code.gitea.io/sdk/gitea"
)

func main() {
	// Create a logger to write error messages
	logFile, err := os.OpenFile("action.log", os.O_CREATE|os.O_WRONLY|os.O_APPEND, 0666)
	if err != nil {
		fmt.Printf("Error while creating the log file: %v\n", err)
		os.Exit(1)
	}
	defer logFile.Close()
	multiWriter := io.MultiWriter(os.Stdout, logFile)
	logger := log.New(multiWriter, "", log.LstdFlags)

	// Retrieve environment variables
	issueOdooTicketString := os.Getenv("ODOO_TICKET_NUMBER")
	logger.Printf("ODOO_TICKET_NUMBER: %s\n", issueOdooTicketString)

	issueTitle := os.Getenv("ISSUE_TITLE")

	labelsEnv := os.Getenv("ISSUE_LABELS")
	logger.Printf("ISSUE_LABELS: %s\n", labelsEnv)

	issueNumberString := os.Getenv("ISSUE_NUMBER")

	giteaToken := os.Getenv("GITEA_TOKEN")
	giteaAPIURL := "https://gitea.ethumada.com"
	repoOwner := os.Getenv("REPO_OWNER")
	repoName := os.Getenv("REPO_NAME")

	if issueOdooTicketString == "" || issueNumberString == "" || issueTitle == "" || giteaToken == "" || repoOwner == "" || repoName == "" {
		logger.Println("Error: some environment variables are missing.")
		os.Exit(1)
	}

	// Convert the issue number to int64
	issueNumber, err := strconv.ParseInt(issueNumberString, 10, 64)
	if err != nil {
		logger.Printf("Error while converting the issue number: %v\n", err)
		os.Exit(1)
	}

	// Convert the odoo ticket number to int64
	issueOdooTicketID, err := strconv.ParseInt(issueOdooTicketString, 10, 64)
	if err != nil {
		logger.Printf("Error while converting the Odoo ticket number: %v\n", err)
		os.Exit(1)
	}
	logger.Printf("Odoo ticket ID: %d\n", issueOdooTicketID)

	// Map labels to Git Flow prefixes
	labels := parseLabels(labelsEnv, logger)
	if len(labels) > 0 {
		logger.Printf("Extracted labels: %s\n", strings.Join(labels, ", "))
	}
	prefix := "feature"
	prefix, err = getPrefixFromLabels(labels)
	if err != nil {
		logger.Printf("Error while determining the prefix: %v\n", err)
		os.Exit(1)
	}
	logger.Printf("Chosen prefix: %s\n", prefix)

	// Form the branch name in the format "prefix/ticket-number"
	branchName := fmt.Sprintf("%s/ticket-%d", prefix, issueOdooTicketID)

	logger.Printf("Branch name set to: %s\n", branchName)

	// Configure Git
	logger.Println("Configuring Git...")
	err = runCommand(logger, "git", "config", "--global", "user.name", "gitea-actions")
	if err != nil {
		logger.Printf("Error while configuring Git: %v\n", err)
		os.Exit(1)
	}

	err = runCommand(logger, "git", "fetch", "origin")
	if err != nil {
		logger.Printf("Error while updating remote references")
		os.Exit(1)
	}

	err = runCommand(logger, "git", "config", "--global", "user.email", "actions@gitea.com")
	if err != nil {
		logger.Printf("Error while configuring Git: %v\n", err)
		os.Exit(1)
	}

	// Check if the branch already exists
	logger.Printf("Checking if branch '%s' exists...\n", branchName)
	output, err := exec.Command("git", "ls-remote", "--heads", "origin", branchName).CombinedOutput()
	if err != nil {
		logger.Printf("Error while checking the branch: %v\nOutput: %s\n", err, string(output))
		os.Exit(1)
	}

	branchExists := false
	if strings.TrimSpace(string(output)) != "" {
		branchExists = true
	}

	if branchExists {
		logger.Printf("Branch '%s' already exists. No action taken.\n", branchName)
	} else {
		// Create and push the branch
		originBranch := "origin/develop"

		logger.Printf("Prefix is : %s", prefix)
		if prefix == "hotfix" {
			originBranch = "origin/main"
		} else {
			logger.Printf("hotfix != %s", prefix)
		}

		logger.Printf("Creating branch '%s' from '%s'.\n", branchName, originBranch)
		err = runCommand(logger, "git", "checkout", "-b", branchName, originBranch)
		if err != nil {
			logger.Printf("Error while creating the branch: %v\n", err)
			os.Exit(1)
		}

		err = runCommand(logger, "git", "push", "origin", branchName)
		if err != nil {
			logger.Printf("Error while pushing the branch: %v\n", err)
			os.Exit(1)
		}

		logger.Printf("Branch '%s' successfully created and pushed.\n", branchName)
	}

	// Assign the branch to the issue via the Gitea API
	logger.Printf("Assigning branch '%s' to issue #%d.\n", branchName, issueOdooTicketID)

	// Create the Gitea client
	client, err := gitea.NewClient(giteaAPIURL, gitea.SetToken(giteaToken))
	if err != nil {
		logger.Printf("Error while creating the Gitea client: %v\n", err)
		os.Exit(1)
	}

	// Prepare options to edit the issue
	editIssueOption := gitea.EditIssueOption{
		Ref: &branchName,
	}

	// Update the issue with the branch reference
	_, _, err = client.EditIssue(repoOwner, repoName, issueNumber, editIssueOption)
	if err != nil {
		logger.Printf("Error while assigning the branch to the issue: %v\n", err)
		os.Exit(1)
	}

	logger.Printf("Branch '%s' successfully assigned to issue #%d.\n", branchName, issueNumber)
}

// Function to map labels to prefixes
func getPrefixFromLabels(labels []string) (string, error) {
	// Define the label ➔ prefix correspondence
	labelPrefixMap := map[string]string{
		"enhancement": "feature",
		"invalid":     "bugfix",
		"bug":         "hotfix",
	}

	// Create a mapping with lower-case keys
	labelPrefixMapLower := make(map[string]string)
	for key, value := range labelPrefixMap {
		keyLower := strings.ToLower(key)
		labelPrefixMapLower[keyLower] = value
	}

	for _, label := range labels {
		trimmed := strings.TrimSpace(label)
		labelLower := strings.ToLower(trimmed)
		fmt.Printf("Current label: %s\n", labelLower)
		if prefix, exists := labelPrefixMapLower[labelLower]; exists {
			return prefix, nil
		}
	}

	return "feature", nil
}

// Parse ISSUE_LABELS env which can be:
// - JSON array of strings: ["bug", "enhancement"]
// - JSON array of objects: [{"name":"bug"},{"name":"ui"}]
// - Comma-separated string: "bug, enhancement"
func parseLabels(raw string, logger *log.Logger) []string {
	raw = strings.TrimSpace(raw)
	if raw == "" {
		return nil
	}

	// Try JSON array of strings
	var arrStr []string
	if err := json.Unmarshal([]byte(raw), &arrStr); err == nil {
		return arrStr
	}

	// Try JSON array of objects with name
	type lbl struct {
		Name string `json:"name"`
	}
	var arrObj []lbl
	if err := json.Unmarshal([]byte(raw), &arrObj); err == nil {
		out := make([]string, 0, len(arrObj))
		for _, o := range arrObj {
			if o.Name != "" {
				out = append(out, o.Name)
			}
		}
		if len(out) > 0 {
			return out
		}
	}

	// Fallback: comma-separated values
	if strings.Contains(raw, ",") {
		parts := strings.Split(raw, ",")
		for i := range parts {
			parts[i] = strings.TrimSpace(parts[i])
		}
		return parts
	}

	// Last resort: if it looks like JSON but couldn't parse, log and return nil
	if strings.HasPrefix(raw, "[") || strings.HasPrefix(raw, "{") {
		logger.Printf("Warning: could not parse ISSUE_LABELS JSON: %s\n", raw)
		return nil
	}

	// Otherwise single token
	return []string{raw}
}

func runCommand(logger *log.Logger, name string, arg ...string) error {
	cmd := exec.Command(name, arg...)
	cmd.Stdout = os.Stdout
	cmd.Stderr = os.Stderr
	logger.Printf("Executing command: %s %s\n", name, strings.Join(arg, " "))
	return cmd.Run()
}