package main

import (
	"bytes"
	"encoding/json"
	"log"
	"net/http"
	"os"
	"os/exec"
	"path/filepath"
	"time"

	"github.com/nicepkg/jarvis/transform"
)

type CompileRequest struct {
	Language string `json:"language"`
	Source   string `json:"source"`
}

type CompileResponse struct {
	Success bool     `json:"success"`
	Wasm    []byte   `json:"wasm,omitempty"`
	Size    int      `json:"size,omitempty"`
	TimeMS  int64    `json:"time_ms,omitempty"`
	Errors  []string `json:"errors,omitempty"`
}

type Language struct {
	Value string `json:"value"`
	Label string `json:"label"`
}

var languages = []Language{
	{Value: "typescript", Label: "TypeScript"},
	{Value: "go", Label: "Go"},
}

func main() {
	port := os.Getenv("PORT")
	if port == "" {
		port = "8090"
	}

	http.HandleFunc("/health", healthHandler)
	http.HandleFunc("/compile", compileHandler)
	http.HandleFunc("/languages", languagesHandler)
	http.HandleFunc("/hooks", hooksHandler)
	http.HandleFunc("/template", templateHandler)
	http.HandleFunc("/sdk", sdkHandler)
	http.HandleFunc("/lsp", lspHandler)

	log.Printf("Jarvis listening on :%s", port)
	log.Fatal(http.ListenAndServe(":"+port, nil))
}

func healthHandler(w http.ResponseWriter, r *http.Request) {
	w.WriteHeader(http.StatusOK)
	w.Write([]byte("ok"))
}

func languagesHandler(w http.ResponseWriter, r *http.Request) {
	w.Header().Set("Content-Type", "application/json")
	json.NewEncoder(w).Encode(languages)
}

func hooksHandler(w http.ResponseWriter, r *http.Request) {
	w.Header().Set("Content-Type", "application/json")
	json.NewEncoder(w).Encode(hooks)
}

func templateHandler(w http.ResponseWriter, r *http.Request) {
	hook := r.URL.Query().Get("hook")
	language := r.URL.Query().Get("language")

	if hook == "" {
		hook = "post.published"
	}
	if language == "" {
		language = "typescript"
	}

	template := GetTemplate(hook, language)

	w.Header().Set("Content-Type", "application/json")
	json.NewEncoder(w).Encode(map[string]string{
		"template": template,
		"hook":     hook,
		"language": language,
	})
}

func compileHandler(w http.ResponseWriter, r *http.Request) {
	if r.Method != http.MethodPost {
		http.Error(w, "Method not allowed", http.StatusMethodNotAllowed)
		return
	}

	var req CompileRequest
	if err := json.NewDecoder(r.Body).Decode(&req); err != nil {
		respondError(w, "Invalid request body")
		return
	}

	start := time.Now()
	var resp CompileResponse

	switch req.Language {
	case "typescript":
		resp = compileTypeScript(req.Source)
	case "go":
		resp = compileGo(req.Source)
	default:
		respondError(w, "Unsupported language: "+req.Language)
		return
	}

	resp.TimeMS = time.Since(start).Milliseconds()
	w.Header().Set("Content-Type", "application/json")
	json.NewEncoder(w).Encode(resp)
}

func respondError(w http.ResponseWriter, msg string) {
	w.Header().Set("Content-Type", "application/json")
	json.NewEncoder(w).Encode(CompileResponse{Success: false, Errors: []string{msg}})
}

func compileTypeScript(source string) CompileResponse {
	// Transform source from clean API to Extism-compatible format
	transformed, err := transform.TypeScript(source)
	if err != nil {
		return CompileResponse{Success: false, Errors: []string{"Transform error: " + err.Error()}}
	}

	tmpDir, err := os.MkdirTemp("", "jarvis-ts-*")
	if err != nil {
		return CompileResponse{Success: false, Errors: []string{err.Error()}}
	}
	defer os.RemoveAll(tmpDir)

	srcFile := filepath.Join(tmpDir, "plugin.ts")
	outFile := filepath.Join(tmpDir, "plugin.wasm")
	dtsFile := filepath.Join(tmpDir, "index.d.ts")

	if err := os.WriteFile(srcFile, []byte(transformed), 0644); err != nil {
		return CompileResponse{Success: false, Errors: []string{err.Error()}}
	}

	// Copy the Extism d.ts file - extism-js requires interface declarations
	sdkDts, err := os.ReadFile("/app/sdk/extism.d.ts")
	if err != nil {
		return CompileResponse{Success: false, Errors: []string{"Failed to read SDK d.ts: " + err.Error()}}
	}
	if err := os.WriteFile(dtsFile, sdkDts, 0644); err != nil {
		return CompileResponse{Success: false, Errors: []string{err.Error()}}
	}

	cmd := exec.Command("extism-js", srcFile, "-i", dtsFile, "-o", outFile)
	var stderr bytes.Buffer
	cmd.Stderr = &stderr

	if err := cmd.Run(); err != nil {
		return CompileResponse{Success: false, Errors: []string{stderr.String()}}
	}

	wasm, err := os.ReadFile(outFile)
	if err != nil {
		return CompileResponse{Success: false, Errors: []string{err.Error()}}
	}

	return CompileResponse{Success: true, Wasm: wasm, Size: len(wasm)}
}

func compileGo(source string) CompileResponse {
	// Transform source from clean API to Extism-compatible format
	transformed, err := transform.Go(source)
	if err != nil {
		return CompileResponse{Success: false, Errors: []string{"Transform error: " + err.Error()}}
	}

	tmpDir, err := os.MkdirTemp("", "jarvis-go-*")
	if err != nil {
		return CompileResponse{Success: false, Errors: []string{err.Error()}}
	}
	defer os.RemoveAll(tmpDir)

	srcFile := filepath.Join(tmpDir, "main.go")
	outFile := filepath.Join(tmpDir, "plugin.wasm")

	if err := os.WriteFile(srcFile, []byte(transformed), 0644); err != nil {
		return CompileResponse{Success: false, Errors: []string{err.Error()}}
	}

	if err := os.WriteFile(filepath.Join(tmpDir, "go.mod"), []byte(`
module writekit-plugin

go 1.22

require github.com/extism/go-pdk v1.0.6
`), 0644); err != nil {
		return CompileResponse{Success: false, Errors: []string{err.Error()}}
	}

	// Run go mod tidy to fetch dependencies and create go.sum
	tidyCmd := exec.Command("go", "mod", "tidy")
	tidyCmd.Dir = tmpDir
	var tidyStderr bytes.Buffer
	tidyCmd.Stderr = &tidyStderr
	if err := tidyCmd.Run(); err != nil {
		return CompileResponse{Success: false, Errors: []string{"Failed to tidy dependencies: " + tidyStderr.String()}}
	}

	cmd := exec.Command("tinygo", "build", "-o", outFile, "-target", "wasi", srcFile)
	cmd.Dir = tmpDir
	var stderr bytes.Buffer
	cmd.Stderr = &stderr

	if err := cmd.Run(); err != nil {
		return CompileResponse{Success: false, Errors: []string{stderr.String()}}
	}

	wasm, err := os.ReadFile(outFile)
	if err != nil {
		return CompileResponse{Success: false, Errors: []string{err.Error()}}
	}

	return CompileResponse{Success: true, Wasm: wasm, Size: len(wasm)}
}