// Copyright 2020-2026 Buf Technologies, Inc.
//
// 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.

package bufworkspace

import (
	"buf.build/go/standard/xslices"
	"github.com/bufbuild/buf/private/pkg/normalpath"
)

// WorkspaceBucketOption is an option for a new Workspace created by a Bucket.
type WorkspaceBucketOption interface {
	applyToWorkspaceBucketConfig(*workspaceBucketConfig)
}

// WorkspaceModuleKeyOption is an option for a new Workspace created by a ModuleKey.
type WorkspaceModuleKeyOption interface {
	applyToWorkspaceModuleKeyConfig(*workspaceModuleKeyConfig)
}

// WorkspaceBucketAndModuleKeyOption is an option for a new Workspace created by either a Bucket or ModuleKey.
type WorkspaceBucketAndModuleKeyOption interface {
	WorkspaceBucketOption
	WorkspaceModuleKeyOption
}

// WithProtoFileTargetPath returns a new WorkspaceBucketOption that specifically targets
// a single .proto file, and optionally targets all other .proto files that are in the same package.
//
// If targetPath is empty, includePackageFiles is ignored.
// Exclusive with WithTargetPaths - only one of these can have a non-empty value.
//
// This is used for ProtoFileRefs only. Do not use this otherwise.
func WithProtoFileTargetPath(protoFileTargetPath string, includePackageFiles bool) WorkspaceBucketOption {
	return &workspaceProtoFileTargetPathOption{
		protoFileTargetPath: protoFileTargetPath,
		includePackageFiles: includePackageFiles,
	}
}

// WithIgnoreAndDisallowV1BufWorkYAMLs returns a new WorkspaceBucketOption that says
// to ignore dependencies from buf.work.yamls at the root of the bucket, and to also
// disallow directories with buf.work.yamls to be directly targeted.
//
// This is used for v1 updates with buf mod prune and buf mod update.
//
// A the root of the bucket targets a buf.work.yaml, but the targetSubDirPath targets
// a module, this is allowed.
//
// Example: ./buf.work.yaml, targetSubDirPath = foo/bar, foo/bar/buf.yaml and foo/bar/buf.lock v1
// This will result in the dependencies from buf.work.yaml being ignored, and a Workspace
// with just the Module at foo/bar plus the dependencies from foo/bar/buf.lock being added.
//
// Example: ./buf.work.yaml, targetSubDirPath = .
// This will result in an error.
//
// Example: ./buf.yaml v1.
// This is fine.
func WithIgnoreAndDisallowV1BufWorkYAMLs() WorkspaceBucketOption {
	return &workspaceIgnoreAndDisallowV1BufWorkYAMLsOption{}
}

// WithTargetPaths specifies the target paths.
//
// Note these paths need to have the path/to/module stripped, and then each new path
// filtered to the specific module it applies to. If some modules do not have any
// target paths, but we specified WorkspaceWithTargetPaths, then those modules
// need to be built as non-targeted.
//
// These paths have to  be within the subDirPath, if it exists.
func WithTargetPaths(targetPaths []string, targetExcludePaths []string) WorkspaceModuleKeyOption {
	return &workspaceTargetPathsOption{
		targetPaths:        targetPaths,
		targetExcludePaths: targetExcludePaths,
	}
}

// WithConfigOverride applies the config override.
//
// This flag will only work if no buf.work.yaml is detected, and the buf.yaml is a v1beta1
// buf.yaml, v1 buf.yaml, or no buf.yaml. This flag will not work if a buf.work.yaml is
// detected, or a v2 buf.yaml is detected.
//
// If used with NewWorkspaceForModuleKey, this has no effect on the build,
// i.e. excludes are not respected, and the module name is ignored. This matches old behavior.
//
// This implements the deprecated --config flag.
//
// See bufconfig.GetBufYAMLFileForPrefixOrOverride for more details.
//
// *** DO NOT USE THIS OUTSIDE OF THE CLI AND/OR IF YOU DON'T UNDERSTAND IT. ***
// *** DO NOT ADD THIS TO ANY NEW COMMANDS. ***
//
// Current comments that use this: build, breaking, lint, generate, format,
// export, ls-breaking-rules, ls-lint-rules.
func WithConfigOverride(configOverride string) WorkspaceBucketAndModuleKeyOption {
	return &workspaceConfigOverrideOption{
		configOverride: configOverride,
	}
}

// *** PRIVATE ***

type workspaceTargetPathsOption struct {
	targetPaths        []string
	targetExcludePaths []string
}

func (t *workspaceTargetPathsOption) applyToWorkspaceModuleKeyConfig(config *workspaceModuleKeyConfig) {
	config.targetPaths = t.targetPaths
	config.targetExcludePaths = t.targetExcludePaths
}

type workspaceProtoFileTargetPathOption struct {
	protoFileTargetPath string
	includePackageFiles bool
}

func (p *workspaceProtoFileTargetPathOption) applyToWorkspaceBucketConfig(config *workspaceBucketConfig) {
	config.protoFileTargetPath = p.protoFileTargetPath
	config.includePackageFiles = p.includePackageFiles
}

type workspaceConfigOverrideOption struct {
	configOverride string
}

func (c *workspaceConfigOverrideOption) applyToWorkspaceBucketConfig(config *workspaceBucketConfig) {
	config.configOverride = c.configOverride
}

func (c *workspaceConfigOverrideOption) applyToWorkspaceModuleKeyConfig(config *workspaceModuleKeyConfig) {
	config.configOverride = c.configOverride
}

type workspaceIgnoreAndDisallowV1BufWorkYAMLsOption struct{}

func (c *workspaceIgnoreAndDisallowV1BufWorkYAMLsOption) applyToWorkspaceBucketConfig(config *workspaceBucketConfig) {
	config.ignoreAndDisallowV1BufWorkYAMLs = true
}

type workspaceBucketConfig struct {
	protoFileTargetPath             string
	includePackageFiles             bool
	configOverride                  string
	ignoreAndDisallowV1BufWorkYAMLs bool
}

func newWorkspaceBucketConfig(options []WorkspaceBucketOption) (*workspaceBucketConfig, error) {
	config := &workspaceBucketConfig{}
	for _, option := range options {
		option.applyToWorkspaceBucketConfig(config)
	}
	if config.protoFileTargetPath != "" {
		config.protoFileTargetPath = normalpath.Normalize(config.protoFileTargetPath)
	}
	return config, nil
}

type workspaceModuleKeyConfig struct {
	targetPaths        []string
	targetExcludePaths []string
	configOverride     string
}

func newWorkspaceModuleKeyConfig(options []WorkspaceModuleKeyOption) (*workspaceModuleKeyConfig, error) {
	config := &workspaceModuleKeyConfig{}
	for _, option := range options {
		option.applyToWorkspaceModuleKeyConfig(config)
	}
	var err error
	config.targetPaths, err = xslices.MapError(
		config.targetPaths,
		normalpath.NormalizeAndValidate,
	)
	if err != nil {
		return nil, err
	}
	config.targetExcludePaths, err = xslices.MapError(
		config.targetExcludePaths,
		normalpath.NormalizeAndValidate,
	)
	if err != nil {
		return nil, err
	}
	return config, nil
}