// Copyright 2026 Alibaba Group
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

// Command cmd_param_aliases reduces the reviewed parameter concept dictionary
// (internal/cli/param_concepts.json) against the live Cobra command tree and
// writes the deterministic per-command alias table to
// internal/cli/param_aliases_generated.go.
//
// The reduction algorithm lives in package cli (cli.ReduceParamAliases) so the
// build-time intersection and the runtime normalizer share exactly one
// implementation. This command is a thin, deterministic serializer: it never
// invents identity, and it fails closed on any un-whitelisted co-occurrence,
// missing override path, or non-real alias target.
package main

import (
	"bytes"
	"flag"
	"fmt"
	"go/format"
	"os"
	"sort"
	"strings"

	"github.com/DingTalk-Real-AI/dingtalk-workspace-cli/internal/app"
	"github.com/DingTalk-Real-AI/dingtalk-workspace-cli/internal/cli"
	"github.com/DingTalk-Real-AI/dingtalk-workspace-cli/internal/generator/outputguard"
)

const defaultOutput = "internal/cli/param_aliases_generated.go"

var (
	newParamAliasRoot       = app.NewSchemaSourceRootCommand
	reduceParamAliasEntries = cli.ReduceParamAliases
	formatParamAliasSource  = format.Source
	writeParamAliasFile     = os.WriteFile
	exitParamAliasProcess   = os.Exit
)

func main() {
	var rootPath string
	var outputPath string
	flag.StringVar(&rootPath, "root", ".", "Repository root used to protect generator inputs")
	flag.StringVar(&outputPath, "output", defaultOutput, "Output generated parameter-alias table")
	flag.Parse()

	if err := generateParamAliases(rootPath, outputPath); err != nil {
		fail(err)
	}
}

func generateParamAliases(rootPath, outputPath string) error {
	if err := validateOutputIsolation(rootPath, outputPath); err != nil {
		return err
	}

	entries, err := reduceParamAliasEntries(newParamAliasRoot())
	if err != nil {
		return err
	}

	source, err := renderParamAliases(entries)
	if err != nil {
		return err
	}
	if err := writeParamAliasFile(outputPath, source, 0o644); err != nil {
		return fmt.Errorf("write generated parameter aliases: %w", err)
	}

	_, _ = fmt.Fprintf(os.Stderr, "generated parameter aliases: output=%s commands=%d\n", outputPath, len(entries))
	return nil
}

func validateOutputIsolation(rootPath, outputPath string) error {
	inputs := []outputguard.Input{
		{Name: "reviewed parameter concept dictionary", Path: "internal/cli/param_concepts.json"},
		{Name: "reviewed parameter concept schema", Path: "internal/cli/param_concepts.schema.json"},
	}
	target := outputguard.Target{Name: "--output", Path: outputPath}
	if err := outputguard.Validate(rootPath, inputs, []outputguard.Target{target}); err != nil {
		return err
	}
	return outputguard.ValidateRepoTargetAllowlist(rootPath, target, defaultOutput)
}

// renderParamAliases serializes the reduced entries into gofmt-stable Go
// source. Entries and every map/slice are emitted in sorted order so
// consecutive generations are byte-identical.
func renderParamAliases(entries []cli.ParamAliasEntry) ([]byte, error) {
	var b bytes.Buffer
	b.WriteString("// Copyright 2026 Alibaba Group\n")
	b.WriteString("// Licensed under the Apache License, Version 2.0 (the \"License\");\n\n")
	b.WriteString("// Code generated by cmd_param_aliases; DO NOT EDIT.\n")
	b.WriteString("// Source: internal/cli/param_concepts.json reduced against the live Cobra tree.\n")
	b.WriteString("// Regenerate with `make generate-schema` (or `go generate ./internal/cli`).\n\n")
	b.WriteString("package cli\n\n")
	b.WriteString("// generatedParamAliases is the per-command parameter-alias table reduced from\n")
	b.WriteString("// the reviewed concept dictionary. Each entry binds one runnable Cobra leaf.\n")
	b.WriteString("var generatedParamAliases = []ParamAliasEntry{\n")

	for _, entry := range entries {
		b.WriteString("\t{\n")
		fmt.Fprintf(&b, "\t\tCLIPath: %q,\n", entry.CLIPath)
		if len(entry.Aliases) > 0 {
			b.WriteString("\t\tAliases: map[string]string{\n")
			for _, key := range sortedKeys(entry.Aliases) {
				fmt.Fprintf(&b, "\t\t\t%q: %q,\n", key, entry.Aliases[key])
			}
			b.WriteString("\t\t},\n")
		}
		if len(entry.Blocked) > 0 {
			fmt.Fprintf(&b, "\t\tBlocked: %s,\n", renderStringSlice(entry.Blocked))
		}
		if len(entry.Ambiguous) > 0 {
			fmt.Fprintf(&b, "\t\tAmbiguous: %s,\n", renderStringSlice(entry.Ambiguous))
		}
		b.WriteString("\t},\n")
	}
	b.WriteString("}\n")
	b.WriteString("\nfunc loadGeneratedParamAliases() []ParamAliasEntry {\n")
	b.WriteString("\treturn generatedParamAliases\n")
	b.WriteString("}\n")

	formatted, err := formatParamAliasSource(b.Bytes())
	if err != nil {
		return nil, fmt.Errorf("format generated parameter aliases: %w", err)
	}
	return formatted, nil
}

func renderStringSlice(values []string) string {
	quoted := make([]string, len(values))
	for i, v := range values {
		quoted[i] = fmt.Sprintf("%q", v)
	}
	return "[]string{" + strings.Join(quoted, ", ") + "}"
}

func sortedKeys(m map[string]string) []string {
	keys := make([]string, 0, len(m))
	for key := range m {
		keys = append(keys, key)
	}
	sort.Strings(keys)
	return keys
}

func fail(err error) {
	_, _ = fmt.Fprintln(os.Stderr, "error:", err)
	exitParamAliasProcess(1)
}