package api_gen

import (
	"bytes"
	"go/format"
	"os"
	"path/filepath"
	"text/template"
)

func generateClient(outputDir string, pkg *APIPackage) error {
	tmpl := `// Code generated by api_gen. DO NOT EDIT.

package client

import (
	"bytes"
	"context"
	"encoding/json"
	"fmt"
	"io"
	"net/http"
	"time"

	"{{ .PkgPath }}"
)

type Client struct {
	BaseURL    string
	Client *http.Client
}

func NewClient(baseURL string) *Client {
	return &Client{
		BaseURL:    baseURL,
		Client: &http.Client{Timeout: 30 * time.Second},
	}
}

{{ $ := . }}

{{ range .Endpoints }}
func (c *Client) {{.Name}}(ctx context.Context, req *{{ $.PkgName }}.{{.ReqType}}) (*{{ $.PkgName }}.{{.ResType}}, error) {
	reqBody, err := json.Marshal(req)
	if err != nil {
		return nil, fmt.Errorf("failed to marshal request: %w", err)
	}

	httpReq, err := http.NewRequestWithContext(ctx, "{{.Method}}", c.BaseURL+"{{.Path}}", bytes.NewBuffer(reqBody))
	if err != nil {
		return nil, fmt.Errorf("failed to create request: %w", err)
	}
	httpReq.Header.Set("Content-Type", "application/json")

	resp, err := c.Client.Do(httpReq)
	if err != nil {
		return nil, fmt.Errorf("failed to execute request: %w", err)
	}
	defer resp.Body.Close()

	if resp.StatusCode != http.StatusOK {
		body, _ := io.ReadAll(resp.Body)
		return nil, fmt.Errorf("request failed with status %d: %s", resp.StatusCode, string(body))
	}

	var res {{ $.PkgName }}.{{.ResType}}
	if err := json.NewDecoder(resp.Body).Decode(&res); err != nil {
		return nil, fmt.Errorf("failed to decode response: %w", err)
	}

	return &res, nil
}
{{ end }}
`

	tmplObj := template.Must(template.New("client").Parse(tmpl))

	var buf bytes.Buffer
	if err := tmplObj.Execute(&buf, pkg); err != nil {
		return err
	}

	unformatted := buf.Bytes()
	formatted, err := format.Source(unformatted)
	if err != nil {
		return err
	}

	return os.WriteFile(filepath.Join(outputDir, "client.go"), formatted, 0644)
}