Two-stage codegen: React + Vue + Svelte from one schema

Stage 1 (framework-agnostic):
  types.ts           — OpenAPI interfaces
  contexts/<name>.ts — fetchXxxContext(params) using mizanFetch
  mutations/<name>.ts — callXxx(args) using mizanCall
  functions/<name>.ts — callXxx(args) using mizanCall
  index.ts           — re-exports

Stage 2 (per framework):
  react.tsx  — hooks + context providers + SSR hydration
  vue.ts     — composables with provide/inject + ref/computed
  svelte.ts  — writable/derived store factories

New packages:
  mizan-runtime — the kernel (~200 lines, zero framework deps)
    configure(), initSession(), registerContext(), invalidate(),
    mizanFetch(), mizanCall(), MizanError
  mizan-vue     — Vue adapter (package.json, codegen template)
  mizan-svelte  — Svelte adapter (package.json, codegen template)

CLI: mizan-generate --target react,vue,svelte
Config: target: 'react' (default) in django.config.mjs

Verified: codegen produces 33 functions across 2 contexts,
14 plain functions, 0 mutations, generating all three Stage 2
outputs from one schema fetch.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

packages/mizan-django/generate/generator/lib/adapters/react.mjs

@@ -0,0 +1,160 @@
+/**
+ * React Stage 2 — Generates hooks + context providers from Stage 1 output.
+ */
+
+function pascalCase(str) {
+    return str.split(/[.\-_]/).map(p => p.charAt(0).toUpperCase() + p.slice(1)).join('')
+}
+
+export function generateReactAdapter(schema) {
+    const functions = schema['x-mizan-functions'] || []
+    const contextGroups = schema['x-mizan-contexts'] || {}
+    const namedContexts = Object.entries(contextGroups).filter(([n]) => n !== 'global')
+    const globalContexts = functions.filter(fn => fn.isContext === 'global')
+    const mutations = functions.filter(fn => !fn.isContext && !fn.isForm && fn.affects)
+    const plainFns = functions.filter(fn => !fn.isContext && !fn.isForm && !fn.affects)
+
+    const lines = [
+        "'use client'",
+        '',
+        '// AUTO-GENERATED by mizan — do not edit',
+        '',
+        "import { createContext, useContext, useState, useEffect, useCallback, type ReactNode } from 'react'",
+        "import { registerContext, mizanCall, mizanFetch } from '@mizan/runtime'",
+        '',
+    ]
+
+    // Import from Stage 1
+    const stage1Imports = []
+    for (const [ctxName] of Object.entries(contextGroups)) {
+        const p = pascalCase(ctxName)
+        stage1Imports.push(`fetch${p}Context`, `type ${p}ContextData`, `type ${p}ContextParams`)
+    }
+    for (const fn of [...mutations, ...plainFns]) {
+        stage1Imports.push(`call${pascalCase(fn.camelName)}`)
+    }
+    if (stage1Imports.length > 0) {
+        lines.push(`import { ${stage1Imports.join(', ')} } from '../index'`)
+        lines.push('')
+    }
+
+    // ── Global context hooks ────────────────────────────────────────────
+
+    if (globalContexts.length > 0) {
+        const p = pascalCase('global')
+
+        lines.push(`// Global context — fetched once at app init`)
+        lines.push(`const GlobalCtx = createContext<${p}ContextData | null>(null)`)
+        lines.push('')
+
+        lines.push(`export function GlobalContextProvider({ children }: { children: ReactNode }) {`)
+        lines.push(`    const [data, setData] = useState<${p}ContextData | null>(() => {`)
+        lines.push(`        if (typeof window === 'undefined') return null`)
+        lines.push(`        const ssr = (window as any).__MIZAN_SSR_DATA__`)
+        lines.push(`        return ssr ?? null`)
+        lines.push(`    })`)
+        lines.push('')
+        lines.push(`    const refetch = useCallback(async () => {`)
+        lines.push(`        const result = await fetch${p}Context({} as any)`)
+        lines.push(`        setData(result)`)
+        lines.push(`    }, [])`)
+        lines.push('')
+        lines.push(`    useEffect(() => { if (!data) refetch() }, [data, refetch])`)
+        lines.push(`    useEffect(() => registerContext('global', {}, refetch), [refetch])`)
+        lines.push('')
+        lines.push(`    return <GlobalCtx.Provider value={data}>{children}</GlobalCtx.Provider>`)
+        lines.push('}')
+        lines.push('')
+
+        for (const fn of globalContexts) {
+            const hookPascal = pascalCase(fn.camelName)
+            lines.push(`export function use${hookPascal}(): ${fn.outputType} {`)
+            lines.push(`    const ctx = useContext(GlobalCtx)`)
+            lines.push(`    if (!ctx) throw new Error('use${hookPascal} requires GlobalContextProvider')`)
+            lines.push(`    return ctx.${fn.name}`)
+            lines.push('}')
+            lines.push('')
+        }
+    }
+
+    // ── Named context providers ─────────────────────────────────────────
+
+    for (const [ctxName, ctxMeta] of namedContexts) {
+        const p = pascalCase(ctxName)
+        const ctxFunctions = functions.filter(fn => fn.isContext === ctxName)
+        const paramEntries = Object.entries(ctxMeta.params || {})
+
+        lines.push(`// ${p} context`)
+        lines.push(`const ${p}Ctx = createContext<${p}ContextData | null>(null)`)
+        lines.push('')
+
+        // Provider
+        lines.push(`export function ${p}Context({ children, ...params }: ${p}ContextParams & { children: ReactNode }) {`)
+        lines.push(`    const [data, setData] = useState<${p}ContextData | null>(() => {`)
+        lines.push(`        if (typeof window === 'undefined') return null`)
+        lines.push(`        const ssr = (window as any).__MIZAN_SSR_DATA__`)
+        if (ctxFunctions.length > 0) {
+            lines.push(`        if (ssr?.${ctxFunctions[0].name} !== undefined) return ssr`)
+        }
+        lines.push(`        return null`)
+        lines.push(`    })`)
+        lines.push('')
+        lines.push(`    const refetch = useCallback(async () => {`)
+        lines.push(`        const result = await fetch${p}Context(params)`)
+        lines.push(`        setData(result)`)
+
+        const deps = paramEntries.map(([pName]) => `params.${pName}`)
+        lines.push(`    }, [${deps.join(', ')}])`)
+        lines.push('')
+        lines.push(`    useEffect(() => { refetch() }, [refetch])`)
+        lines.push(`    useEffect(() => registerContext('${ctxName}', params, refetch), [${deps.join(', ')}, refetch])`)
+        lines.push('')
+        lines.push(`    return <${p}Ctx.Provider value={data}>{children}</${p}Ctx.Provider>`)
+        lines.push('}')
+        lines.push('')
+
+        // Hooks
+        for (const fn of ctxFunctions) {
+            const hookPascal = pascalCase(fn.camelName)
+            lines.push(`export function use${hookPascal}(): ${fn.outputType} | null {`)
+            lines.push(`    const ctx = useContext(${p}Ctx)`)
+            lines.push(`    return ctx?.${fn.name} ?? null`)
+            lines.push('}')
+            lines.push('')
+        }
+    }
+
+    // ── Mutation hooks ──────────────────────────────────────────────────
+
+    for (const fn of mutations) {
+        const p = pascalCase(fn.camelName)
+        if (fn.hasInput) {
+            lines.push(`export function use${p}() {`)
+            lines.push(`    return useCallback((args: Parameters<typeof call${p}>[0]) => call${p}(args), [])`)
+            lines.push('}')
+        } else {
+            lines.push(`export function use${p}() {`)
+            lines.push(`    return useCallback(() => call${p}(), [])`)
+            lines.push('}')
+        }
+        lines.push('')
+    }
+
+    // ── Plain function hooks ────────────────────────────────────────────
+
+    for (const fn of plainFns) {
+        const p = pascalCase(fn.camelName)
+        if (fn.hasInput) {
+            lines.push(`export function use${p}() {`)
+            lines.push(`    return useCallback((args: Parameters<typeof call${p}>[0]) => call${p}(args), [])`)
+            lines.push('}')
+        } else {
+            lines.push(`export function use${p}() {`)
+            lines.push(`    return useCallback(() => call${p}(), [])`)
+            lines.push('}')
+        }
+        lines.push('')
+    }
+
+    return lines.join('\n')
+}