package config

import (
	"fmt"
	"regexp"

	"gitgud.io/mike/mpv-manager/pkg/constants"
)

const hwaMethodAlternation = `auto|auto-safe|nvdec|nvdec-copy|vaapi|vaapi-copy|vulkan|vulkan-copy|d3d11va|d3d11va-copy|videotoolbox|videotoolbox-copy|drm|drm-copy|no`

// validMPVConfigValues is shared by every interactive configuration surface.
// Keeping this allowlist below the Web and TUI packages prevents either UI
// from accepting text that can escape an mpv.conf value onto another line.
var validMPVConfigValues = map[string]*regexp.Regexp{
	constants.ConfigKeyHardwareDecoder:          regexp.MustCompile(`^(` + hwaMethodAlternation + `)(,(` + hwaMethodAlternation + `)){0,3}$`),
	constants.ConfigKeyVideoOutput:              regexp.MustCompile(`^[a-zA-Z0-9_-]+$`),
	constants.ConfigKeyScaleFilter:              regexp.MustCompile(`^[a-zA-Z0-9_-]+$`),
	constants.ConfigKeyDitherAlgorithm:          regexp.MustCompile(`^(no|ordered|error-diffusion|floyd-steinberg)$`),
	constants.ConfigKeySavePositionOnQuit:       regexp.MustCompile(`^(yes|no)$`),
	constants.ConfigKeyBorder:                   regexp.MustCompile(`^(yes|no)$`),
	constants.ConfigKeyProfile:                  regexp.MustCompile(`^(high-quality|fast|low-latency|sw-fast)$`),
	constants.ConfigKeyScreenshotFormat:         regexp.MustCompile(`^(png|jpg|jpeg|webp|jxl|avif)$`),
	constants.ConfigKeyScreenshotTagColorspace:  regexp.MustCompile(`^(yes|no)$`),
	constants.ConfigKeyScreenshotHighBitDepth:   regexp.MustCompile(`^(yes|no)$`),
	constants.ConfigKeyScreenshotTemplate:       regexp.MustCompile(`^[a-zA-Z0-9_\-\.%:, ()]+$`),
	constants.ConfigKeyScreenshotDirectory:      regexp.MustCompile(`^[\w/\\\-.~:, ]+$`),
	constants.ConfigKeyScreenshotJpegQuality:    regexp.MustCompile(`^(100|[1-9]?\d)$`),
	constants.ConfigKeyScreenshotPngCompression: regexp.MustCompile(`^[0-9]$`),
	constants.ConfigKeyScreenshotWebpLossless:   regexp.MustCompile(`^(yes|no)$`),
	constants.ConfigKeyScreenshotWebpQuality:    regexp.MustCompile(`^(100|[1-9]?\d)$`),
	constants.ConfigKeyScreenshotJxlDistance:    regexp.MustCompile(`^(15\.0|([0-9]|1[0-4])(\.\d)?|[0-9]|1[0-5])$`),
	constants.ConfigKeyScreenshotAvifEncoder:    regexp.MustCompile(`^[a-zA-Z0-9\-]+$`),
	constants.ConfigKeyScreenshotAvifPixfmt:     regexp.MustCompile(`^[a-zA-Z0-9_\-]*$`),
	constants.ConfigKeyScreenshotAvifOpts:       regexp.MustCompile(`^[a-zA-Z0-9_=,\-\.]+$`),
}

// ValidateMPVConfigValue validates a key/value accepted by the interactive
// config editors. Values not represented in the allowlist fail closed.
func ValidateMPVConfigValue(key, value string) error {
	pattern, ok := validMPVConfigValues[key]
	if !ok {
		return fmt.Errorf("invalid config key: %s", key)
	}
	if !pattern.MatchString(value) {
		return fmt.Errorf("invalid value %q for key %q", value, key)
	}
	return nil
}