restructure project following best practices

https://go.dev/doc/modules/layout
This also enables us to later import just the db interaction part
say to the gemini capsule backend go project.

internal/ui/write.go

@@ -0,0 +1,141 @@
+package ui
+
+import (
+	"fmt"
+	"os"
+	"os/exec"
+	"strings"
+	"time"
+
+	gemlog "git.travisshears.com/travisshears/gemlog-cli/gemlog"
+	tea "github.com/charmbracelet/bubbletea"
+	"gopkg.in/yaml.v3"
+)
+
+// TODO: add edit command
+// func EditPostCMD(config *gemlog.Config) tea.Cmd {}
+
+func WritePostCMD(config *gemlog.Config) tea.Cmd {
+	return func() tea.Msg {
+		// Create a temporary file
+		tmpFile, err := os.CreateTemp("/tmp", "gemlog-*.md")
+		if err != nil {
+			return ErrorMsg{fmt.Errorf("failed to create temporary file: %w", err)}
+		}
+
+		// Load initial content from template file
+		initialContent, err := os.ReadFile("templates/default_post.gmi")
+		if err != nil {
+			tmpFile.Close()
+			os.Remove(tmpFile.Name())
+			return ErrorMsg{fmt.Errorf("failed to read template file: %w", err)}
+		}
+
+		if _, err := tmpFile.Write(initialContent); err != nil {
+			tmpFile.Close()
+			os.Remove(tmpFile.Name())
+			return ErrorMsg{fmt.Errorf("failed to write initial content: %w", err)}
+		}
+		tmpFile.Close()
+
+		// Get the editor from environment variable, default to vim
+		editor := os.Getenv("EDITOR")
+		if editor == "" {
+			editor = "vim"
+		}
+
+		// Create the command to open the editor with the temp file
+		c := exec.Command(editor, tmpFile.Name()) //nolint:gosec
+
+		// Return tea.ExecProcess which will suspend the TUI and run the editor
+		return tea.ExecProcess(c, func(err error) tea.Msg {
+			defer os.Remove(tmpFile.Name()) // Clean up the temp file
+
+			if err != nil {
+				return ErrorMsg{fmt.Errorf("editor command failed: %w", err)}
+			}
+
+			// Read the contents of the file after editing
+			content, readErr := os.ReadFile(tmpFile.Name())
+			if readErr != nil {
+				return ErrorMsg{fmt.Errorf("failed to read file contents: %w", readErr)}
+			}
+
+			gemlogEntry, err := parsePost(string(content))
+			if err != nil {
+				return ErrorMsg{fmt.Errorf("failed to parse post: %w", err)}
+			}
+			if err := gemlog.SaveGemlogEntry(config, &gemlogEntry); err != nil {
+				return ErrorMsg{fmt.Errorf("failed to save gemlog entry: %w", err)}
+			}
+
+			// Return success with the content
+			return Notification(fmt.Sprintf("Post created: \ngemini://travisshears.com/gemlog/%s\n\n", gemlogEntry.Slug))
+		})()
+	}
+}
+
+func parsePost(post string) (gemlog.GemlogEntry, error) {
+	// split post on new lines
+	lines := strings.Split(post, "\n")
+
+	// Find the separator line "---"
+	separatorIndex := -1
+	for i, line := range lines {
+		if strings.TrimSpace(line) == "---" {
+			separatorIndex = i
+			break
+		}
+	}
+
+	if separatorIndex == -1 {
+		return gemlog.GemlogEntry{}, fmt.Errorf("no frontmatter separator '---' found")
+	}
+
+	// Extract frontmatter and body
+	frontmatterLines := lines[:separatorIndex]
+	bodyLines := lines[separatorIndex+1:]
+
+	// Parse frontmatter YAML
+	frontmatterYAML := strings.Join(frontmatterLines, "\n")
+
+	var frontmatter struct {
+		Title string `yaml:"title"`
+		Date  string `yaml:"date"`
+		Slug  string `yaml:"slug"`
+		Tags  string `yaml:"tags"`
+	}
+
+	if err := yaml.Unmarshal([]byte(frontmatterYAML), &frontmatter); err != nil {
+		return gemlog.GemlogEntry{}, fmt.Errorf("failed to parse frontmatter: %w", err)
+	}
+
+	// Parse date
+	date, err := time.Parse("2006-01-02", strings.TrimSpace(frontmatter.Date))
+	if err != nil {
+		return gemlog.GemlogEntry{}, fmt.Errorf("failed to parse date: %w", err)
+	}
+
+	// Parse tags (comma-separated)
+	var tags []string
+	if frontmatter.Tags != "" {
+		tagParts := strings.Split(frontmatter.Tags, ",")
+		for _, tag := range tagParts {
+			trimmed := strings.TrimSpace(tag)
+			if trimmed != "" {
+				tags = append(tags, trimmed)
+			}
+		}
+	}
+
+	// Join body lines
+	body := strings.Join(bodyLines, "\n")
+
+	return gemlog.GemlogEntry{
+		Title:  frontmatter.Title,
+		Date:   date,
+		Slug:   frontmatter.Slug,
+		Tags:   tags,
+		Gemtxt: body,
+	}, nil
+}