package aiprompts

import "strings"

// Prompt keys stored in ai_prompt_templates.prompt_key.
const (
	KeyProductEnhance = "product_enhance"
	KeySEOMeta        = "seo_meta"
	KeyCampaignEmail  = "campaign_email"
)

// MaxSystemRunes / MaxUserRunes bound stored templates (prompt-injection surface).
const (
	MaxSystemRunes = 6000
	MaxUserRunes   = 4000
)

// Variable describes a placeholder tenants can insert into templates.
type Variable struct {
	Name        string `json:"name"`
	Label       string `json:"label"`
	Description string `json:"description"`
	Keys        []string `json:"keys"` // prompt_key values that support this variable
}

// Catalog of supported {{variables}} (only these are substituted; unknown tokens stay literal).
var VariableCatalog = []Variable{
	{Name: "name", Label: "Product name", Description: "Current product title", Keys: []string{KeyProductEnhance, KeySEOMeta}},
	{Name: "description", Label: "Description", Description: "Current product description", Keys: []string{KeyProductEnhance, KeySEOMeta}},
	{Name: "category", Label: "Category", Description: "Resolved category name", Keys: []string{KeyProductEnhance, KeySEOMeta}},
	{Name: "attrs", Label: "Attributes", Description: "Compact JSON of product attributes", Keys: []string{KeyProductEnhance}},
	{Name: "gtin", Label: "GTIN", Description: "Product GTIN / barcode when present", Keys: []string{KeyProductEnhance}},
	{Name: "brand", Label: "Brand name", Description: "Company or product brand label", Keys: []string{KeySEOMeta, KeyCampaignEmail}},
	{Name: "brand_voice", Label: "Brand voice", Description: "Brand kit tone / dos / don'ts block", Keys: []string{KeyProductEnhance, KeySEOMeta, KeyCampaignEmail}},
	{Name: "language", Label: "Content language", Description: "Company content language (English display name)", Keys: []string{KeyProductEnhance, KeySEOMeta, KeyCampaignEmail}},
	{Name: "campaign_prompt", Label: "Campaign brief", Description: "Per-campaign user brief or template default", Keys: []string{KeyCampaignEmail}},
	{Name: "products", Label: "Product list", Description: "Plain-text product snippets for the campaign", Keys: []string{KeyCampaignEmail}},
	{Name: "template_key", Label: "Template key", Description: "Campaign template id (christmas, custom, …)", Keys: []string{KeyCampaignEmail}},
}

// DefaultTemplate is the built-in prompt when the company has no custom row or disabled it.
type DefaultTemplate struct {
	Key            string `json:"key"`
	Label          string `json:"label"`
	Description    string `json:"description"`
	SystemTemplate string `json:"system_template"`
	UserTemplate   string `json:"user_template"`
}

// CategoryEnhanceUserTemplate is the shared per-category (and built-in) enhance USER
// message. Includes {{name}} {{description}} {{attrs}} {{category}} {{language}}.
// Compatible with the enhance system JSON schema {"name","description"} — not a
// competing HTML marketing document. Title/description formulas stay in
// title_template / description_template and are appended at render time as plain
// text instructions (see processing.AppendFormulaConstraints).
// Used by local A1/Demo prompt repair and seed-a1 overlays.
const CategoryEnhanceUserTemplate = `Your reply is parsed as JSON {"name":"string","description":"string"} only (system schema). Write name and description in {{language}} (do not hardcode a language).
- name: short retail title; follow any Title formula constraints that follow; use Attrs
- description: when a Description formula follows, emit ONE HTML string covering each section in order (tags matching type: h1/h2/h3/h4, p, ul); otherwise prefer 1-3 factual paragraphs as ONE string with limited HTML (<h2><p><ul><li>) — do NOT emit a competing full HTML document, <name>/<metaDescription> blocks, or separate schema

Category: {{category}}
Name: {{name}}
Desc: {{description}}
Attrs: {{attrs}}`

// CategoryEnhancePromptNeedsRepair reports whether a stored categories.prompt value
// should be replaced by CategoryEnhanceUserTemplate (idempotent equality check).
func CategoryEnhancePromptNeedsRepair(prompt string) bool {
	p := strings.TrimSpace(prompt)
	if p == "" {
		return false
	}
	return p != strings.TrimSpace(CategoryEnhanceUserTemplate)
}

// BuiltInDefaults match the previous hardcoded system prompts, with structured user templates.
var BuiltInDefaults = []DefaultTemplate{
	{
		Key:         KeyProductEnhance,
		Label:       "Product title & description",
		Description: "Used when processing products (AI enhance step).",
		SystemTemplate: `Retail product copywriter.
Rules:
- Reply with ONLY JSON (no markdown)
- Schema: {"name":"string","description":"string"}
- name: short retail title
- description: follow any Description formula in the user message (structured HTML sections); otherwise 1-3 factual paragraphs; never copy name as description
- When Desc is empty or the same as Name, write from Category and Attrs only (do not invent specs); still obey a Description formula when present
- Write name and description in {{language}}
Example:
{"name":"Acme Widget Pro","description":"Durable widget for everyday use. Clear specs, ready to ship."}
{{brand_voice}}`,
		UserTemplate: CategoryEnhanceUserTemplate,
	},
	{
		Key:         KeySEOMeta,
		Label:       "SEO meta title & description",
		Description: "Used when applying AI SEO meta to a product.",
		SystemTemplate: `SEO meta writer for ecommerce.
Rules:
- Reply with ONLY JSON (no markdown)
- Schema: {"meta_title":"string","meta_description":"string"}
- meta_title: 50-60 chars, product + benefit
- meta_description: 120-155 chars, factual
- Write meta_title and meta_description in {{language}}
Example:
{"meta_title":"Acme Widget Pro | Durable Daily Use","meta_description":"Shop Acme Widget Pro for reliable everyday performance. Clear specs and fast delivery."}
{{brand_voice}}`,
		UserTemplate: `Name: {{name}}
Category: {{category}}
Desc: {{description}}`,
	},
	{
		Key:         KeyCampaignEmail,
		Label:       "Campaign email",
		Description: "Used when generating marketing emails with AI.",
		SystemTemplate: `Marketing email writer.
Rules:
- Reply with ONLY JSON (no markdown)
- Schema: {"subject":"string","html_body":"string","plain_body":"string"}
- subject: short
- html_body: simple HTML (<p>, <ul>, <a> only)
- plain_body: plain text mirror
- Write subject, html_body, and plain_body in {{language}}
Example:
{"subject":"Holiday picks from Acme","html_body":"<p>Season's greetings.</p><ul><li>Widget Pro</li></ul><p><a href=\"#\">Shop now</a></p>","plain_body":"Season's greetings.\n- Widget Pro\nShop now"}
{{brand_voice}}`,
		UserTemplate: `{{campaign_prompt}}

Products:
{{products}}
Brand: {{brand}}
Template: {{template_key}}`,
	},
}

// ValidPromptKey reports whether key is a known prompt_key.
func ValidPromptKey(key string) bool {
	switch key {
	case KeyProductEnhance, KeySEOMeta, KeyCampaignEmail:
		return true
	default:
		return false
	}
}

// DefaultFor returns the built-in default for key, or empty if unknown.
func DefaultFor(key string) (DefaultTemplate, bool) {
	for _, d := range BuiltInDefaults {
		if d.Key == key {
			return d, true
		}
	}
	return DefaultTemplate{}, false
}