feat(lsp): add workspace folder initialization

- Added logic to walk through workspace folders and initialize templ files.
- Logs warnings when source maps are not found in cache.
- Parses templates and sets source map cache contents.
- Handles errors during file reading, template parsing, and generation.

Author: tris203

cmd/templ/lspcmd/proxy/server.go

@@ -3,17 +3,20 @@ package proxy
 import (
 	"context"
 	"fmt"
+	"os"
+	"path/filepath"
 	"regexp"
 	"strings"
 
 	"github.com/a-h/parse"
 	lsp "github.com/a-h/protocol"
+	"go.lsp.dev/uri"
+	"go.uber.org/zap"
+
 	"github.com/a-h/templ"
 	"github.com/a-h/templ/cmd/templ/imports"
 	"github.com/a-h/templ/generator"
 	"github.com/a-h/templ/parser/v2"
-	"go.lsp.dev/uri"
-	"go.uber.org/zap"
 )
 
 // Server is responsible for rewriting messages that are
@@ -81,6 +84,7 @@ func (p *Server) convertTemplRangeToGoRange(templURI lsp.DocumentURI, input lsp.
 	var sourceMap *parser.SourceMap
 	sourceMap, ok = p.SourceMapCache.Get(string(templURI))
 	if !ok {
+		p.Log.Warn("templ->go: sourcemap not found in cache")
 		return
 	}
 	// Map from the source position to target Go position.
@@ -101,6 +105,7 @@ func (p *Server) convertGoRangeToTemplRange(templURI lsp.DocumentURI, input lsp.
 	output = input
 	sourceMap, ok := p.SourceMapCache.Get(string(templURI))
 	if !ok {
+		p.Log.Warn("go->templ: sourcemap not found in cache")
 		return
 	}
 	// Map from the source position to target Go position.
@@ -228,6 +233,51 @@ func (p *Server) Initialize(ctx context.Context, params *lsp.InitializeParams) (
 		Save:              &lsp.SaveOptions{IncludeText: true},
 	}
 
+	for _, c := range params.WorkspaceFolders {
+		path := strings.TrimPrefix(c.URI, "file://")
+		werr := filepath.Walk(path, func(path string, info os.FileInfo, err error) error {
+			if err != nil {
+				return err
+			}
+			uri := uri.URI("file://" + path)
+			isTemplFile, _ := convertTemplToGoURI(uri)
+			if isTemplFile {
+				b, err := os.ReadFile(path)
+				if err != nil {
+					return err
+				}
+				p.Log.Info("found file", zap.String("path", path))
+				if !isTemplFile {
+					return fmt.Errorf("not a templ file")
+				}
+				p.TemplSource.Set(string(uri), NewDocument(p.Log, string(b)))
+				// Parse the template.
+				template, ok, err := p.parseTemplate(ctx, uri, string(b))
+				if err != nil {
+					p.Log.Error("parseTemplate failure", zap.Error(err))
+				}
+				if !ok {
+					p.Log.Info("parsing template did not succeed", zap.String("uri", string(uri)))
+					return nil
+				}
+				w := new(strings.Builder)
+				sm, _, err := generator.Generate(template, w)
+				if err != nil {
+					return fmt.Errorf("generate failure: %w", err)
+				}
+				p.Log.Info("setting source map cache contents", zap.String("uri", string(uri)))
+				p.SourceMapCache.Set(string(uri), sm)
+				// Set the Go contents.
+				p.GoSource[string(uri)] = w.String()
+
+			}
+			return nil
+		})
+		if werr != nil {
+			p.Log.Error("walk error", zap.Error(werr))
+		}
+	}
+
 	result.ServerInfo.Name = "templ-lsp"
 	result.ServerInfo.Version = templ.Version()