${valIdentifier ? `${valIdentifier} - The Book` : \"The Book\"}

${\n selected.explanation.split(\"\\n\\n\").map((para) =>\n `

${parseMarkdownLinks(para)}

`\n ).join(\"\")\n }

`\n : selected\n ? `

Loading explanation...

`\n : error\n ? `

${escapeHtml(error)}

`\n : `

Select a chapter to read

`;\n\n // Raw code in a hidden div, empty code element to be filled by JS\n const codeContent = selected\n ? `

`\n : `

Select a file to view its code

`;\n\n const scriptTag = buildScriptTag();\n\n return `\n\n\n \n \n ${valIdentifier ? `${valIdentifier} - The Book` : \"The Book\"}\n\n \n \n \n\n \n\n\n

\n\n

\n ${middleContent}\n

\n\n

\n ${codeContent}\n

\n\n ${scriptTag}\n\n`;\n}\n\nexport default async function (req: Request): Promise {\n const url = new URL(req.url);\n const valParam = url.searchParams.get(\"val\") || \"\";\n const chapterParam = url.searchParams.get(\"chapter\");\n const selectedIndex = chapterParam ? parseInt(chapterParam, 10) : 0;\n\n let chapters: FileContent[] = [];\n let error: string | undefined;\n\n if (valParam) {\n const parts = valParam.split(\"/\");\n if (parts.length === 2) {\n const [handle, valName] = parts;\n try {\n const valInfo = await fetchValByAlias(handle, valName);\n const files = await fetchValFiles(valInfo.id);\n const codeFiles = filterCodeFiles(files);\n\n chapters = await Promise.all(\n codeFiles.map(async (f) => ({\n name: f.name,\n path: f.path,\n code: await fetchFileContent(valInfo.id, f.path),\n })),\n );\n\n const titles = await generateChapterTitles(valParam, chapters);\n chapters = chapters.map((ch, i) => ({\n ...ch,\n chapterTitle: titles[i],\n }));\n\n if (chapters[selectedIndex]) {\n const explanation = await generateExplanation(\n valParam,\n chapters[selectedIndex],\n );\n chapters[selectedIndex].explanation = explanation;\n }\n } catch (e) {\n error = e instanceof Error ? e.message : \"Failed to fetch val\";\n }\n } else {\n error = \"Invalid val identifier. Use format: handle/valName\";\n }\n }\n\n const validIndex = Math.max(0, Math.min(selectedIndex, chapters.length - 1));\n\n return new Response(renderPage(valParam, chapters, validIndex, error), {\n headers: { \"Content-Type\": \"text/html\" },\n });\n}\n","deleted","label",[100],"permalink","https://www.val.town/x/tmcw/book/code/main.ts","extension","actionData","errors"]