// Package configorch fans Render() out across every per-service
// renderer in a stable order (haproxy → nftables → squid →
// wireguard → unbound). The orchestrator stops on the first hard
// error; ErrNotImplemented stubs are logged but do NOT abort the
// run (squid/wireguard/unbound are stubs in Phase 2).
package configorch

import (
	"context"
	"errors"
	"fmt"
	"strings"

	"git.netcell-it.de/projekte/edgeguard-native/internal/configgen"
)

type Result struct {
	Name      string
	Skipped   bool
	Err       error
	DurationS float64 // populated by callers if they care; orchestrator leaves it 0
}

func (r Result) Status() string {
	switch {
	case r.Err == nil:
		return "ok"
	case errors.Is(r.Err, configgen.ErrNotImplemented):
		return "skipped (stub)"
	default:
		return "error: " + r.Err.Error()
	}
}

// Run invokes Render on every generator in `gens`, returning a per-
// generator Result slice. Stops on the first hard error so a broken
// HAProxy config doesn't bleed into a partial nftables rewrite.
//
// only: optional whitelist of generator names — empty slice means
// "all". Useful for `render-config --only=haproxy` debugging.
func Run(ctx context.Context, gens []configgen.Generator, only []string) ([]Result, error) {
	whitelist := map[string]bool{}
	for _, n := range only {
		whitelist[n] = true
	}
	out := make([]Result, 0, len(gens))
	for _, g := range gens {
		if len(whitelist) > 0 && !whitelist[g.Name()] {
			out = append(out, Result{Name: g.Name(), Skipped: true})
			continue
		}
		err := g.Render(ctx)
		out = append(out, Result{Name: g.Name(), Err: err})
		if err != nil && !errors.Is(err, configgen.ErrNotImplemented) {
			// hard failure — surface it but return what's done so far
			return out, fmt.Errorf("%s: %w", g.Name(), err)
		}
	}
	return out, nil
}

// Summarise turns the result slice into a human-readable multiline
// string. Used by `edgeguard-ctl render-config` to print to stdout.
func Summarise(results []Result) string {
	var b strings.Builder
	for _, r := range results {
		if r.Skipped {
			fmt.Fprintf(&b, "  %-10s  skipped (filtered)\n", r.Name)
			continue
		}
		fmt.Fprintf(&b, "  %-10s  %s\n", r.Name, r.Status())
	}
	return b.String()
}