package tide_test

import (
	"context"
	"errors"
	"fmt"
	"net/http"
	"net/http/httptest"
	"os"

	"git.golem15.com/golem15/summercms/modules/tide"
)

// backend stands in for one implementation of GET /api/blog/posts.
func backend(body string) *httptest.Server {
	return httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		w.Header().Set("Content-Type", "application/json")
		fmt.Fprint(w, body)
	}))
}

func ExampleReplayFlow() {
	ctx := context.Background()
	// The reference (PHP) backend and two Go ports. IDs and *_at timestamps
	// legitimately differ; the second port changed a title.
	reference := backend(`{"data":[{"id":12,"title":"Hello","created_at":"2026-09-30T10:00:00+00:00"}]}`)
	defer reference.Close()
	port := backend(`{"data":[{"id":3,"title":"Hello","created_at":"2026-10-01T08:30:00+00:00"}]}`)
	defer port.Close()
	broken := backend(`{"data":[{"id":3,"title":"hello","created_at":"2026-10-01T08:30:00+00:00"}]}`)
	defer broken.Close()

	raw, err := os.ReadFile("testdata/docs/posts-spec.yaml")
	if err != nil {
		fmt.Println(err)
		return
	}
	spec, err := tide.ParseFlow(raw)
	if err != nil {
		fmt.Println(err)
		return
	}
	// Record the reference once; the flow is what testdata/parity keeps.
	flow, err := tide.RecordFlow(ctx, spec, tide.RecordConfig{Target: reference.URL})
	if err != nil {
		fmt.Println(err)
		return
	}
	for _, target := range []string{port.URL, broken.URL} {
		res, err := tide.ReplayFlow(ctx, flow, tide.ReplayConfig{Target: target})
		var mismatch *tide.MismatchError
		if errors.As(err, &mismatch) {
			res = mismatch.Result // a difference is an error carrying the result
		} else if err != nil {
			fmt.Println(err)
			return
		}
		fmt.Println("ok:", res.OK)
		for _, step := range res.Steps {
			for _, d := range step.Diffs {
				fmt.Printf("  %s %s: want %s, got %s\n", step.ID, d.Path, d.Expected, d.Actual)
			}
		}
	}
	// Output:
	// ok: true
	// ok: false
	//   list-posts $.data[0].title: want "Hello", got "hello"
}