package ckprompt

import (
	"errors"

	commandkit "gitea.maximumdirect.net/eric/CommandKit"
	promptkit "gitea.maximumdirect.net/eric/promptkit"
)

type validationCommandInput[I any] struct {
	promptID string
	request  ValidationRequest
	format   string
	captured commandkit.FlagValues[I]
	selected I
}

type requestValidationReport struct {
	PromptID string `yaml:"prompt_id"`
	Valid    bool   `yaml:"valid"`
}

func newValidationCommand[I, S any](suite Suite[I, S]) commandkit.Command {
	flags := commandkit.CaptureFlags(suite.Selectors, func(input **validationCommandInput[I]) *commandkit.FlagValues[I] {
		if input == nil || *input == nil {
			return nil
		}
		return &(*input).captured
	})
	flags = append(flags,
		commandkit.ValueFlag(commandkit.FlagMeta{Name: "config", Usage: "Configuration input path."}, (*string)(nil), parseDefinitionString,
			func(input **validationCommandInput[I], value commandkit.Supplied[string]) {
				(*input).request.Selection.Config = value
			}),
		commandkit.ValueFlag(commandkit.FlagMeta{Name: "overlay", Usage: "Configuration overlay path."}, (*string)(nil), parseDefinitionString,
			func(input **validationCommandInput[I], value commandkit.Supplied[string]) {
				(*input).request.Selection.Overlay = value
			}),
		commandkit.ValueFlag(commandkit.FlagMeta{Name: "version", Usage: "Prompt version to validate."}, stringDefault(""), parseDefinitionString,
			func(input **validationCommandInput[I], value commandkit.Supplied[string]) {
				(*input).request.Request.PromptVersion = value.Value
			}),
		commandkit.ValueFlag(commandkit.FlagMeta{Name: "profile", Usage: "Profile identity for validation."}, stringDefault(""), parseDefinitionString,
			func(input **validationCommandInput[I], value commandkit.Supplied[string]) {
				(*input).request.Request.ProfileID = value.Value
			}),
		commandkit.ValueFlag(commandkit.FlagMeta{Name: "session-id", Usage: "Session context for validation."}, stringDefault(""), parseDefinitionString,
			func(input **validationCommandInput[I], value commandkit.Supplied[string]) {
				(*input).request.Request.SessionID = value.Value
			}),
		commandkit.ValueFlag(commandkit.FlagMeta{Name: "format", Usage: "Confirmation format: yaml."}, stringDefault("yaml"), parseDefinitionString,
			func(input **validationCommandInput[I], value commandkit.Supplied[string]) {
				(*input).format = value.Value
			}),
		commandkit.RepeatFlag(commandkit.FlagMeta{Name: "var", Usage: "Caller variable assignment KEY=VALUE."}, []variableAssignment(nil), parseVariableAssignment,
			func(input **validationCommandInput[I], value commandkit.Supplied[[]variableAssignment]) {
				variables := make(map[string]string, len(value.Value))
				for _, assignment := range value.Value {
					variables[assignment.key] = assignment.value
				}
				(*input).request.Request.Vars = variables
			}),
		commandkit.RepeatFlag(commandkit.FlagMeta{Name: "input", Usage: "Prompt input file assignment NAME=PATH."}, []inputAssignment(nil), parseInputAssignment,
			func(input **validationCommandInput[I], value commandkit.Supplied[[]inputAssignment]) {
				inputs := make(map[string]promptkit.ArtifactRef, len(value.Value))
				for _, assignment := range value.Value {
					inputs[assignment.name] = promptkit.File(assignment.path)
				}
				(*input).request.Request.Inputs = inputs
			}),
	)

	return commandkit.NewCommand(commandkit.CommandSpec[*validationCommandInput[I]]{
		Name:    "validate",
		Summary: "Validate a concrete PromptKit request without executing it.",
		NewInput: func() *validationCommandInput[I] {
			return &validationCommandInput[I]{format: "yaml"}
		},
		Flags: flags,
		Arguments: []commandkit.Argument[*validationCommandInput[I]]{
			commandkit.ValueArgument(commandkit.ArgumentMeta{Name: "id", Usage: "Prompt ID."}, true, parseDefinitionString,
				func(input **validationCommandInput[I], value commandkit.Supplied[string]) {
					(*input).promptID = value.Value
					(*input).request.Request.PromptID = value.Value
				}),
		},
		CheckInput: func(input *validationCommandInput[I]) error {
			if input == nil {
				return errors.New("PromptKit validation input must not be nil")
			}
			if err := checkRequirementsFormat(input.format); err != nil {
				return err
			}
			selected, err := prepareSuiteInput(suite, input.request.Selection, input.captured)
			if err != nil {
				return err
			}
			input.selected = selected
			return nil
		},
		Run: func(invocation commandkit.Invocation, input *validationCommandInput[I]) commandkit.Outcome {
			return runRequestValidation(invocation, suite, input)
		},
	})
}

func runRequestValidation[I, S any](invocation commandkit.Invocation, suite Suite[I, S], input *validationCommandInput[I]) commandkit.Outcome {
	if err := promptKitContextError(invocation.Context); err != nil {
		return definitionFailure(err, nil)
	}
	var state S
	if suite.NewState != nil {
		state = suite.NewState()
	}
	if err := promptKitContextError(invocation.Context); err != nil {
		return definitionFailure(err, nil)
	}

	acquired, err := suite.ValidateRequest(invocation.Context, input.request, input.selected, state)
	if err != nil {
		return definitionFailure(err, acquired.Diagnostics)
	}
	if err := promptKitContextError(invocation.Context); err != nil {
		return definitionFailure(err, acquired.Diagnostics)
	}
	output, err := encodePromptYAMLBytes(requestValidationReport{PromptID: input.promptID, Valid: true})
	if err != nil {
		return definitionFailure(err, acquired.Diagnostics)
	}
	return writePromptReport(invocation, output, acquired.Diagnostics)
}