package app

import (
	"fmt"
	"sort"
	"strings"

	"gitea.maximumdirect.net/eric/narratio/internal/artifacts"
	"gitea.maximumdirect.net/eric/narratio/internal/config"
)

type artifactSelectionFlag struct {
	values []string
}

func (f *artifactSelectionFlag) String() string {
	return strings.Join(f.values, ",")
}

func (f *artifactSelectionFlag) Set(value string) error {
	f.values = append(f.values, value)
	return nil
}

func (f *artifactSelectionFlag) Normalize() ([]string, error) {
	if len(f.values) == 0 {
		return nil, nil
	}

	seen := map[string]struct{}{}
	out := make([]string, 0, len(f.values))
	for _, raw := range f.values {
		for _, part := range strings.Split(raw, ",") {
			name := strings.TrimSpace(part)
			if name == "" {
				return nil, fmt.Errorf("artifact names must be non-empty")
			}
			if _, ok := seen[name]; ok {
				continue
			}
			seen[name] = struct{}{}
			out = append(out, name)
		}
	}

	sort.Strings(out)
	return out, nil
}

func validateSelectedArtifacts(cfg *config.Config, selected []string) error {
	_, err := resolveEffectiveArtifacts(cfg, selected)
	return err
}

func resolveEffectiveArtifacts(cfg *config.Config, selected []string) (artifacts.EffectiveArtifactSet, error) {
	if cfg == nil || cfg.Pipeline == nil || cfg.Pipeline.Scriptorium == nil {
		if len(selected) == 0 {
			return artifacts.ResolveEffectiveArtifactSet(nil, nil)
		}
		return artifacts.EffectiveArtifactSet{}, fmt.Errorf("--artifacts requires pipeline.scriptorium.artifacts to be configured")
	}
	configured := artifacts.ConfiguredArtifactDefinitions(cfg.Pipeline.Scriptorium.Artifacts)
	normalized, err := normalizeArtifactSelection(cfg, selected)
	if err != nil {
		return artifacts.EffectiveArtifactSet{}, err
	}
	if len(normalized) > 0 && len(configured) == 0 {
		return artifacts.EffectiveArtifactSet{}, fmt.Errorf("--artifacts requires at least one configured artifact in pipeline.scriptorium.artifacts")
	}
	effective, err := artifacts.ResolveEffectiveArtifactSet(configured, normalized)
	if err != nil {
		if strings.Contains(err.Error(), "is not configured") {
			return artifacts.EffectiveArtifactSet{}, fmt.Errorf("--artifacts includes unknown artifact %q", selectedArtifactName(err))
		}
		return artifacts.EffectiveArtifactSet{}, err
	}
	if err := validateEffectiveArtifactConfiguration(cfg.Pipeline.Scriptorium.Artifacts, effective); err != nil {
		return artifacts.EffectiveArtifactSet{}, err
	}
	return effective.WithOrigins(effectiveArtifactOrigins(cfg.Pipeline)), nil
}

func normalizeArtifactSelection(cfg *config.Config, selected []string) ([]string, error) {
	if len(selected) == 0 {
		return nil, nil
	}
	configured := cfg.Pipeline.Scriptorium.Artifacts
	families := config.ArtifactFamilies(cfg.Pipeline).Families
	set := make(map[string]struct{}, len(selected))
	for _, raw := range selected {
		key := strings.TrimSpace(raw)
		if key == "" {
			return nil, fmt.Errorf("artifact names must be non-empty")
		}
		if family, ok := families[key]; ok {
			for _, member := range family.Members {
				set[member] = struct{}{}
			}
			continue
		}
		if _, ok := configured[key]; !ok {
			return nil, fmt.Errorf("--artifacts includes unknown artifact %q", key)
		}
		set[key] = struct{}{}
	}
	normalized := make([]string, 0, len(set))
	for key := range set {
		normalized = append(normalized, key)
	}
	sort.Strings(normalized)
	return normalized, nil
}

func effectiveArtifactOrigins(pipeline *config.PipelineConfig) map[string]artifacts.EffectiveArtifactOrigin {
	catalog := config.ArtifactFamilies(pipeline)
	origins := make(map[string]artifacts.EffectiveArtifactOrigin, len(catalog.Members))
	for key, member := range catalog.Members {
		origins[key] = artifacts.EffectiveArtifactOrigin{Family: member.Family, CharacterID: member.CharacterID}
	}
	return origins
}

func selectedArtifactName(err error) string {
	message := err.Error()
	start := strings.Index(message, "\"")
	if start < 0 {
		return ""
	}
	end := strings.Index(message[start+1:], "\"")
	if end < 0 {
		return ""
	}
	return message[start+1 : start+1+end]
}

func validateEffectiveArtifactConfiguration(configured map[string]config.ScriptoriumArtifactConfig, effective artifacts.EffectiveArtifactSet) error {
	for _, name := range effective.Keys() {
		artifactCfg := configured[name]
		if strings.TrimSpace(artifactCfg.PromptID) == "" {
			return fmt.Errorf("pipeline.scriptorium.artifacts.%s.prompt_id is required when selected", name)
		}
		if strings.TrimSpace(artifactCfg.OutputPath) == "" {
			return fmt.Errorf("pipeline.scriptorium.artifacts.%s.output_path is required when selected", name)
		}
	}
	return nil
}